Retired flight instructor, CPA. As I was watching your videos, I knew only a pilot could have your understanding, at the end of this video you gave it away you had this knowledge, I like your quick and fast definite way of getting your point across. THANKS.
Not sure how many of you noticed, but turn rate varies greatly by speed and altitude. In short just about any plane in WW2 if jumped, the enemy plane was usually in a dive carrying extra speed from the dive, could out turn the enemy by the simple fact your speed is lower. The faster plan could not turn with you. Then the turn radius between different aircraft types all had a best altitude at which it could turn faster than at any other altitude. However no two aircraft shared this same altitude. Means at altitude X airplane Y could outturn airplane Z at same airspeed, but change the altitude and airplane Z could likely outturn airplane Y at same speed. You wanted to fight at the altitude that your plane had the advantage. WW2 flight sims do not model this at all. I add this in because most people only experience with flying is in a flight sim. And you need to know the flight sims are not very accurate as compared to real life flying.
Something my father (a military pilot from the WWII era) said that is pretty obvious is that a turning plane is easier to catch up with. Like a triangle, the turning pilot is flying the adjacent and then opposite leg while the pursuing pilot is flying the hypotenuse - a shorter distance and closing giving a good chance to connect with a deflection shot.
Your vids begin to answer many questions that have hung up discussions "forever". On top of that, you relate things in concrete terms us laymen can grasp that otherwise might have remained mystical. I'm not a pilot, more historian, but history is rife with technology and tech solutions. Love it! "Speed and bank angle"! Can't thank you enough.
Thanks Jeff. I consider this one to be my best video, but it's the least popular. It makes me happy to see that some people like it. I think the concepts are easy to understand once you know the key factors, and simply plot them on the chart.
Can't wait to get into sustained turn rates. I'm amazed that I've read about WW2 plane performance for years without someone laying this stuff out. As you say its just key factors and charts or algebra, but if no one around you knows how to solve a triangle, you just imagine that perhaps there are special people who can. Not very satisfying.
Well done, as usual. I'm neither pilot nor engineer, but find this stuff fascinating because my Dad was a Navy pilot in WW 2 (46 missions in an F6F off the Lexington in 1944 with VF-19, then rotated back home for a transition to the F4U-4 and 9 months of training with VBF-150 until war's end), then a test pilot with McDonnell Aircraft postwar (XF-85, XF-88, F2H, etc.). I'd love to see a similar comparison of those two very successful WW 2 Navy fighters vs. the Zero, the Ki-44 ("Tojo"), or the Ki-84 ("Frank"). Carrier warfare made very different demands on an airframe, pilot and engine than did the higher-altitude fighting more common in Europe.
My RAAF 77 Squadron Technical Officer had flown P51 Mustangs during the Korean War. He told me they would lose in practice 1v1 against RNZAF Corsairs because the Corsair could sustain turn ' energy ' better. Mustang is an energy fighter better suited to ' shoot and scoot ' rather than ' turn and burn '
The presentation that separates the aviator men from the video game fan boys! Aerodynamics for Naval Aviators was handed to us first day at Pensacola! Thanks.
there are a number of people who are both and a number of those who play flight sims and games that research carefully and look through information such as this in order to fact check the games and sims they play. That is a pointless put-down.
Actually not really. I think what he's trying to say is, what the stats say about an aircraft (especially a ww2 aircraft) on paper, is by no means exactly how said aircraft will perform in the air. Plus there are far more things to be taken into consideration that a video game or simulator just cant account for or reproduce. Anyone who has actually flown one of these planes will attest to that.
haha....got me... I had to rewind to take another look.. A36 Apache ground attack aircraft. I remember this one from reading up on the Mustang history in William N Hess's P51 Bomber Escort book.
The P-51’s first notch of flaps can be employed up to ~400 mph, but it seems that the 109’s flaps are more effective when used below the activation speed limit which is > 200 mph.
So many factors in performance and dogfighting I never even considered! And it brings to light what a true high performance aircraft would of had to he able to do back then to really hold a helpful advantage.
@@GregsAirplanesandAutomobiles I just rewatched your video about Boyd. I have read his biography before. I would love to hear more about this and how he helped build the F-16 and other Fighters
I recently got a request for a 109 vs P51 turn radius analysis. I'll do that in the next couple weeks, along with a DR1 vs. Camel in Rise of Flight analysis.
I will be waiting !. One thing about engines ........ I have always been interested in Junkers Jumo 213 . It powered the FW -190 D and TA152. It would be interesting to see how it stacked up compared to Daimler 605 and RR Packard. That said --I really like your videos , most pilots ( not video gamers ) have to love them . Thank you ! .
Also the wing design itself, laminar flow wings on the P51 are made for high alt. They give the pony advantage. Lower the advantage slightly to the 109.
Interesting subject. After watching a video of a Wildcat flying a vertical S, I decided to try it in my Extra 330LC. It gets even more intricate when you consider the dynamics of changing gravitational effect in a vertical S. The Wildcat stacked a half loop on top of an Immelmann. In the Extra, it is possible to stack two Immelmanns (only just). I determined that an Immelmann is possible if you start at 100 KIAS, but you are very low on energy in the roll-off-the-top (around 40 KIAS, unloaded, but with significant torque and propeller slipstream effects due to the low speed and loss of aileron effectiveness). You cannot pull more than 2.5g on the entry, or you will enter an accelerated stall that will rob energy and make it impossible to continue. This means the first (lower) Immelmann must leave you with at least 100 KIAS on its exit to facilitate an immediate second Immelmann. It can be achieved by starting the first Immelmann at around 175-185 KIAS and pulling around 6-7g initially. This will leave 100-120 KIAS available at the start of the second Immelmann. Now to figure out the optimum g to maximize energy retention and attempt to improve the symmetry of the figure (since the top Immelmann is much slower, but occurs at significantly lower g, it is hard to estimate the radius of turn for each). 1g stall in my Extra comes at around 63 KIAS (two up), so 185 KIAS will accommodate an instantaneous 8.5g. G-limit two up is +/-8g, but solo it goes up to +/-10g. I estimate that solo I can run about 15% lighter, which should improve the vertical performance, although inertia may actually be beneficial in the initial “zoom.” The difficulty is optimizing g-loading to maximize performance (high g means you turn tighter (initially), but it significantly increases induced drag and robs energy). A tighter turn radius also reduces the time you spend fighting the Earth’s gravity opposing your thrust. All the quantities are continuously varying, making for some very complicated physics.
Two immelmanns in a row would be quite impressive to see. It makes sense that a really well flown Extra could do it, but I don't recall ever seeing it done.
@@GregsAirplanesandAutomobiles it really consumes the available energy. The second half-roll at the very top (roll to the left) becomes a torque roll at 40 KIAS, so aileron must be centered about 45° early to finish upright with wings level (the torque wants to keep the roll going). It’s also a challenge to keep the whole S in a single plane (i.e. to avoid twisting off plane, especially on the second Immelmann).
And a lot of the difference in performance can be attributed to the regime in which the plane was intended to fight. The NACA Roll rates at speed chart helps with this (as you already know).
I'm very sorry that I saw only now this very interesting video regarding the comparative speed, angle of attack and other factors versus other airplanes including of course the Me 109! Thanks for enlightening me and I will look forward to to see more of your videos! Thanks!!
An additional factor is pitch trim, Airfoils have a (generally) nose down pitching moment that is balanced by the horizontal tail. The tail load is adds to the load already born by the wing as it pulls the plane thru the turn... more induced drag. The Mustang’s airfoil has appreciable pitching moment; the Wildcat’s NACA 23015 has nil. The NACA 230xx series nil pitching moment meant the pilot could throw the plane around without having to trim. The 230xx was used on the Wildcat, Hellcat, Bearcat, Corsair, Lightning, FW190 and Beech Bonanza... it’s been around. Downsides is bad stall, drag, and won’t carry ice.
Centre of mass also affects the amount of control surface movement needed to change direction, and hence the induced drag from the tail feathers ! Bearcat was almost unflyable if you could not see the horizon, not safe at night... !!
First off, thanks for the links Greg! I’ve got a PDF copy of the navy book on my iPad now! After a second look, it was an A36 Apache. Nice! And I’ve been there to see that in person.
I just learned something. When he said is was not a mustang i was already suspecting that this was an Apache. But I started reading the wiki entry and I always thought that the A36 predated the mustang but not that what I found out. Amazing plane with amazing missons.
Please by all means quote Clarence Anderson, Colonel Bud is a one and only. I hope that one day they declassify his wild weasel strategies and let us see the camera footage. I just poured a shot of Old Crow.
I'd like to see the second part of this subject on sustained turn performance. And a third one that lists the various turn rates both instantaneous ans sustained at various speeds and altitudes, for all the major aircraft types in use in WW-II, but I think that is probably too much to ask? As all ways, I love your stuff.
There are many WWII vets who talk about out-turning an ME-109 under the right circumstances - altitude, speed, etc. Often they would drop some flaps that that would enable them to turn inside the ME-109
I watched a video of a Fw 190 ace talking about his experiences dogfighting Mustangs. He basically said that the P-51 had a very strong initial turn, to the point where it would come up behind the six of the German plane, and a lot of novice German pilots lost the nerves and tried to dive away or break off. Which, in most cases was their demise, since you won't outdive a P-51 in a German fighter. He then continued that, if you kept turning with the Mustang, you would eventually catch it again and apparently a lot of the older experienced German veterans knew about this and thus didn't try to break away or dive. Now a 190 is of course different to a 109 but I still thought it was quite interesting. The name of the ace was Willi Reschke.
@@TheSerec That may be true of the BF-109, but a FW-190 will handily out dive anything but a P-47, and isn't really suited to turn against anything. Its roll rate is fantastic, but it bleeds energy like a stuck pig in any but the most gentle turns.
Great videos! I had to laugh when you mentioned one plane absolutely out-turning the other "and vice-versa". Years ago I read a commentary on Zeroes and P-40s. It may have been Murray Rubenstein's excellent comparison series, but I really don't remember for sure. What I do recall is reading a quote from a P-40 pilot to the effect that "I never met a Zero that could out-turn me." Given that pretty much everyone agrees that the Zero was by far the better turner, I learned a little bit about how much perceptions play a part in what we see. If a P-40 pilot takes a shot from 300 yards behind a Zero and the Japanese pilot throws it into a tight turn in an attempt to avoid another shot, the American only has to turn a few degrees to keep him in his sights. Sure, the shot's going to be a much worse deflection shot, but as far the shooter is concerned the Zero is still in front of his guns and it sure looks to him like he easily out-turned his target. Of course personal experience is one of the worst judges of facts, but I can see where a lot of these stories get their start.
"I never met a Zero that could out-turn me." This might be the phenomenon called "survivorship bias" - none of the pilots that were out-turned by Zeroes lived to tell the tale.
sebrafield wtf, now the zero is outterned by p40. Ok I understand american pilots had to lie some to win any medal and be a bit famous I mean profits for them. But why you fall in it!?
The zero was very good at low speed turns. P-40 Pilots learned to keep the air speed up. In high speed turns the zero's controls became very heavy, if it slowed down to make the turn it gave a speed advantage to the P-40, then could not acceleruate fast enough(due to radial engine drag) to escape the P-40's speed advantage.
I've read other places that the turn performance of a P-61 was better than any other fighter of WWII. I haven't watched much of the video above but it sounds like you're concentrating on those 2 aircraft. I was hoping for a more widespread comparison of various craft in a typical war time load for comparison. I watched a Navy F-14 at the Point Mugu Space Fair (their name for their annual air show) do a full 360 degree turn while about 250 feet above sea level within the confines of the base between the outer fence and the runway closest to that fence, where the pilot basically stood the plane at nearly 90 degrees from horizontal and flew that circle and I could hear the jockeying of the throttle and see the shifts in the control surfaces as he flew the circle. I doubt seriously if any WWII fighter could have matched that circle under any circumstances. That pilot certainly earned his pay that day.
It should be noted that RAF and RN Spitfire/Seafire pilots used the Franks water filled G-suit as early as 1942. I've read that they exceeded the structural limits of the Seafire and returned with bent and wrinkled wings. That was Op Torch, so I'll assume it was low level combat.
I absolutely love your meticulous research and data presentation, looking forward to a P-51 vs. 109 turn radius analysis video (and maybe add a spitfire too for reference?) looking forward to your upcoming videos.
Thanks very much. I consider this to be my best video. It sat for about 6 months with only a couple dozen views. I had actually decided not to focus on airframe issues in videos because this video seemed to be such a failure in terms of views. I am glad to see that it's now doing well, and a lot of people like it.
B and C were essentially the same, built at different factories (like the D and the K were essentially the same). The B and C were lighter than the D, the D had the bubble canopy (of course), a thicker wing (which allowed the guns to be mounted upright and alleviated some problems with jamming in the B and C). The heavier weight also made the D slightly slower, as did the bubble canopy (it's actually got more drag than the faired-in birdcage canopy and high turtledeck). IIRC the B and C were usually only fitted with 4 .50 machine guns, the D had 6 (adding to the weight). The D came in quite late, supposedly fully half of the Mustangs in operation in Europe on VE day were still Bs and Cs.
I've read in several articles that a 4-engined Short Stirling bomber could and did out-turn a Bf109. I find that a bit incredible (in correct parlance, not modern parlance).
Hmm, I won't say it couldn't have happened. If the Stirling was as a lower speed, and the 109 was way too fast, then maybe, or if the 109 was way too slow, or damaged, again, it could happen, but in any apples to apples comparison, or a sustained turn the 109 will easily out turn the Stirling.
This is super interesting video. Also that plane in the beginning, I thought it looked weird to be P51 but thought I was mistaken lol I can't really pinpoint any differences but it looks odd to me(and yeah after reading the comments I found out it was A36)
And that's a GOOD thing! Was hoping for more than a treatise on turn performance between these two warbirds (may two favorties of all time) Thanks in advance! : D
With the laminar flow wing the p-51s maneuverability was improved at around 400 kmh. And was a brick at lower speeds. The saber had the same issue so that’s another factor it reduced turbulence on the wings when turning allowing to to maintain speed. And be able to pull tight turns where any other design (like the 109) would loose manuevering performance due to turbulence on the wing root this is unique to the p-51 and what made it so futuristic. I just wanted to contribute this
laminar flow wasnt archived due to distortion of airflow from propeller and guns, also rivets. laminar flow was only archived in models. laminar wings produce much less drag at the cost of less lift, so it doesnt help maneuverbility. laminar flow was only archived after war with specially prepared wing surfaces. reason to use such airfoils is lower drag= higher speed, better fuel consumption, which is essential for a long range escort fighter.
Lemsko that’s not entirely true. The p-51s wings were thinner at wing root and tip it’s wings were specifically designed for high speed maneuvers. They played with many design. Mostly using math and theory. The p-51s wings are what makes it unique they were also used on saber which is noted as the cause of some of its landing issues The reduced turbulence meant it could hold energy better. And turn better against high amounts of speed. You don’t honestly think they just threw planes together back then because they didn’t have a wind tunnel and hope they worked?
they havnt archived laminar flow in real flight. the advantage vs conventional airfoils is the much lower drag they produce. i dont say it is bad, it was exceptional at that time compared to other planes. take a short reading here: wp1113056.server-he.de/ABL/20-forschung/laminarfluegel/laminarfluegel_en.htm
as i remember USA had no windtunnel capable of testing high speed, the results are from german windtunnel tests. After war they archived laminar flow with extra prepared wings, but not over whole wing, gun ports and propeller area couldnt produce laminar flow even with nearly perfect surface. Mustang is definitely a absolute great design for an efficiant low drag aircraft.
5:00 that explains a heck of a lot about the P-38 being so surprisingly agile, honestly. It was a poor sustained turner, but in the right conditions, it could hold with Zekes for a brief moment
i live in belgium;, we use metric. i had to convert everything to metric. wich is pretty time consuming;, yet i foiund it an informative and fun video :) greetz from Belgium :)
Thanks Sean. In Belgium they use feet for altitude measurement and knots for airspeed. I fly over Belgium all the time, so I know. Linkage: www.eurocontrol.int/muac . However, I get that a lot of people like the metric system, so I'll include those numbers from now on.
Interesting video series. While the P51 mustang is my favorite aircraft of all time it's interesting to see a proper analysis to see how much what I know or think I know is just myth and bull shit. To be honest I think timing of the mustang introduction plays a huge part in it's success in Europe but to win air superiority over a foreign country is a huge victory. The germans out numbered the RAF 6:1 and lost the battle of Britain and they had airfields in France the Americans did it from England for the most part. Home ground advantage is a big force multiplier. I'll be watching your series to learn more. keep up the good work and thank you.
Corporal Punishment come on dude you really think the British had a fighter vs fighter kd of 6-1. They won the battle of Britian because the Germans had no need to win it. They wanted peace with the British. It was a waste of oil and resource to fight them.
Ryan, you might be one of like 12 people who know that the Germans were actually trying to get peace with the British. The historical political correctness revisionist police are going to show up at your door.
Interesting points , but consider a few facts The British where not short on planes due too a ramp up in production , it was experienced pilots that where the major problem , British tactics at the time where not too fight over France so the Germans mistakenly thought the RAF had fewer planes than they actually did. The Me-109 and Supermarine Spitfire and Hawker Hurricane where all short range point defense fighters , The Me-109 had 12 minutes of Endurance over London , Any German aircraft shot down where a total loss of an aircraft and captured crew if they bailed out , Where as the British if they survived just had a replacement aircraft. Its a 108 miles from London too Calais , and that is a long way too nurse a damaged aircraft low on fuel possibly leaking coolant and maybe Oil. The biggest problems the Germans ever faced where they never ever had enough fuel and what they did have was synthesized mostly from coal and was defiantly lower quality and Octane that the British had . Add to this most German pilots had been flying and fighting since 1939, some of these even carried on with little respite till 1945 truly remarkable really .
German's seeking peace? By peace you mean surrender. They were obviously intent on victory, a "peace" in the same sense that France was 'at peace' with Germany by then. Germany could have sought peace without initiating a bombing campaign. They let it go when they realized to their surprise that the Brits were not going to be easy like they had recently become accustomed to. America could have been at peace with Japan and Germany simply by giving in and letting them run roughshod over the top of the nation. Just SURRENDER! How hard is THAT?? (tho some have noted that it would be a long futile fight with every other American civilian hiding behind a tree and picking off invading soldiers with hunting rifles regardless of Washington's policies--I like to think so) If the Jews could do it over I guarantee they would NOT have "gone with the flow" they would have kept their guns and fought it out in the streets against the Nazi's, better to die fighting then be led defenseless to your death as a slave labor at best or in to a gas chamber. Same goes for the rest of us.
Bo McGillacutty Saying that Germany wanted peace with Great Britain is like saying Hitler wanted peace with Russia. Then Germany invaded Russia, I would not say Germany wanted peace with Great Britain but delay or stop it's further involvement like Sweden when Norway was invaded. Ultimately Germany attacked the UK so when people say Hitler wanted peace is a bit strange to me.
This is a great channel. Im only an Arm Chair pilot but I think comparing a p51 turn radius to a bf109's would be like comparing Ford Mustang super snake to a Lotus Exige S. you can Tell every bit of the Bf-109 was made for turning. Even Roll rate, Which I don't even think can be compared... x6 50.cal Machine guns plus amo hanging out in the wings, plus over 2,000 lbs heavier. As you said Turn rate may be close though. but if I think of roll rate+ turn rate +climb rate id say My money is on the bf-109.
I was talking to an old FM-2 pilot at an airshow years ago. He said that the FM-2 was way better than a wildcat. It had a lot more real world power and was very maneuverable. He said that they had no problem with zeros. In a turning fight he said the FM-2 could eat any other airplane alive
The FM-2 Wildcat is a really cool forgotten page of USN fighter history. A lot of people don't realize that the Wildcat stayed around after the Hellcat took over the main carriers.
I have to say I don't know why the P-51 doesn't have the air brakes the A-36 has. They can be an assist in an aerial dogfight, by reducing the speed and causing an opponent to overshoot. However, you would have to be quick and smart to then use that to your advantage.
Why does everyone forget about the P-38? The P-38 was the only WWII fighter with Fowler flaps that provided lower stall speed in addition to drag. With one notch of flaps, a P-38 J model had a power on stall speed below 60 knots. The aircraft had a notch on the flap level that allowed the pilot to ''slap' the flaps to this setting. This gave it the tightest turn radius of any American or European fighter. Only the Zeek and Oscar could out turn it. You don't hear about this much because American doctrine was boom and zoom rather than turn and burn.
I remember reading about one P-38 pilot who claimed that at low altitude he could outturn any plane, but it involved differential engine power and a pitch up - basically the P-38 could be going in the opposite direction faster than any other plane, changing direction 180 degrees.
Walter Eichhorn, a well known German pilot who flew the Messerschmitt "red 7" and participated in the filming of "Memphis Belle", later told me very much the same during a dinner. Furthermore in his opinion a Bf 109 G-10/K-4 was capable of outturning a P-51 D without difficulty (Eichhorn flew both types).
The K was about as numerous as the Me-262, there weren't enough of them to even consider. Might as well compare it to the P-51H, which would've outperformed ANY German propeller driven plane, in every aspect, during the war...
@@princesofthepower3690 It absolutely would have. Also, there were so few of the 190D11, D13, and 109Ks produced, a Mustang pilot was about as likely to see a unicorn as they were seeing any of these planes...
Hi Greg. Would it be a available for you to do a video on the reason for the different positions of the horizontal stab. Example, why are the P-51 and zero hor. stabs forward of where the F4F wildcats are. I would have thought the further back the horizontal Stabilizer and elevator, example, the F-22 Raptor, the more mechanical force generated to point the nose. Thanks again for your videos, love the educational value.
That's a complicated subject but I'll try to sum up. 1. For stability, you want the rudder as far aft of the CG as possible. Also, the farther aft it is, the smaller it can be and still provide adequate control and stability. So that's why you might want it as far back as you can get it. 2. For a fighter aircraft, you don't want it too stable. It needs to be able to maneuver quickly. A larger, more forward rudder can help this. 3. I suspect the main reason for a more forward rudder is structural. It puts a lot of torque on the fuselage and the fuselage is very small in cross section at the tail. Moving the rudder forward attaches it to the fuselage at a much stiffer and stronger point. 4. In cases where the rudder is actually behind the elevator, extreme elevator angles (say a tight turn) can disrupt the airflow to the rudder, reducing its effectiveness. Moving the rudder forward keeps it in cleaner air.
Thank you for a great video. Not a pilot but I have flown and my most memorable experience was in a t-34 when we rolled 90, no back stick, and Dropped Like a Rock intentionally, no rudder, as to be expected. Is top rudder used in these high bank angle steep turns? Thanks.
Many P-38 pilots found that at lower altitudes in a turn against a 109 you add power to the up-wing engine, reduce power to the down-wing engine, and open the Fowler flaps about 10 degrees. You cut right inside of him where those 4 50 cals and single 20mm cannon cut him in half like a rip saw through balsa wood. Just ask Robin Olds. He loved his P-51 but understood the capabilities of his P-38 and pretty much every aircraft he flew. I think pilot skill is the best determining factor in turn radius.
If the two planes are equal in turn performance, then pilot skill will be the determining factor. The farther apart they are, the less it matters, For example, any Japanese pilot in a Zero in 1941 could out turn any US pilot in a Brewster Buffalo, and do it at any given speed.
Ah.. that "not a P-51" at the beginning of the video is the A-36 (officially "Apache") displayed at the Wright Patterson AFB museum at Dayton. I must've visited it 3 or 4 times over the years. The dive flaps are down and you can see the yellow identification stripe painted under (and I think over) the wings, because it resembled a Me-109 in the air. For those who haven't come across the A36 - it's the dive bomber version of what became the P-51, with the Allison V-1710. These were the first "Mustangs" used by the USAAF, mainly in Italy. Lots of people seem to have the opinion that the Allison Mustang was a lousy fighter - this is very far from the truth. It was faster than anything else available at the time on the deck, and the British made good use of it starting in late 1942. IIRC they only lost one to enemy fighters, while it was fully capable of engaging and shooting down Me-109s and FW-190s at the altitudes it was used at (mainly for rhubarbs and low level reconnaissance).
iskandartaib I mean, not like the brits would have taken it over the kittyhawks they originally asked for if it was crummy, right? Not to mention the Rhubarb missions mmmm.... Rhubarb
And also, the big incentive for improving its high altitude performance with a Merlin was that it was already known as a fast, superlative fighter with long range. If it was a lousy fighter they wouldn't have done it in the first place. (They did put Packard Merlins in the P-40 by the way - P40F/P40L - not sure if it was a one or two stage supercharged Merlin - but they didn't use them for high altitude long-range bomber escort.) I have the book published by Rolls Royce about the conversion (the "Mustang X") - it wasn't trivial. They had to re-route quite a bit of ducting and move components around to get the Merlin to fit.
The Wikipedia page says it did improve high altitude performance (the single stage Merlin was also used in the Spitfire V, which was used at high altitude) but it probably made no difference on the deck which is where they were mostly used (in North Africa).
iskandartaib The Merlin in the P40 did slightly increase the service ceiling but not much, and the Allison could NOT be beat at the lower altitudes !!! Did not change overall or total performance !!! And the Allison was easier to maintain !!!
One more point. Turn radius or pretty much any turn ability can be negated with the right tactics. Claire Chenault's P-40s were slower than Zeros, could not turn or climb with Zeros and they shot down scads of zeros by attacking from a higher altitude and zoomed through the Zero formation much faster than the zeros could dive and then continue their dive and pull a zoom climb out away from the conflict and return again from higher altitude to do it again, and again etc.
Rate should be part of this title, discussion as well( it is later in the video) , as it isn't just turn radius, it's rate in terms of degrees per second which determine turn performance overall, many new flyers don't figure this out initially.
The single hardest thing when making these videos is somehow coming up with a title that makes everyone happy. I am not concerned about it because I am not going for clicks, I am going for content.
Fair enough, don't take this as negative criticism either, my point is only that so many pilots online in combat sims frequently don't understand that turn performance isn't just a matter of turn radius, and that rate plays just as important a roll, as do other factors. Which, again, I feel you explained very well in the video. I'm really enjoying your content, glad I found your channel, and I'll point others I fly with online here, some great videos. Plus I dig your small performance car vids, I've had a few Miatas and an Alfa 4C (and dozens of other performance cars). Please keep making content like this, the 109 stuff is especially great, been a 109 fan since I was a kid, and fly it in Aces High almost exclusively for the last 20 years online, and DCS and IL2's 109 models as well. My uncle built scale R/C models when I was a kid, and worked in that industry for years, and won a bunch of awards with his 109F4 model he built in the 80s (I have lots of pictures of this particular model). Ever since, I've read everything I could find on the 109, plus a neighbor my father had at his cabin was a German LW WW2 pilot, and was involved in the M163 project near the end of the war, and flew several models of 109. I wish I'd recorded all the conversations I'd had with him...
4:45 -- I feel like you and I are on the same metaphorical page at many points during this discussion. At the top of the video, you noted that there's two issues at hand: (a) minimum turning radius, and (b) maximum turning rate. And at that time, I said to myself -- that's not tough to keep separated! (A) will be a function of SPEED, whereas (B) will be a function of ACCELERATION (which we'll be calling thrust, or available power). Yay, high school physics and maths. :D
Also! I *LULZ* when you say "...assuming that this turn will be at a constant altitude." In my mind, that's the same as saying "....by keeping a constant Speed." Applying Thrust (ie. Acceleration) is the same as changing altitude, normally to go Up. It's a useful way to keep a constant altitude while co-ordinated turning, though.
One critical thing was omitted in this video: maximal lift coefficient CLmax depends on Mach number, so, if it is derived from 1g stall speed with low Mach, it is not suitable to calculate high speed and high-g turn performance. The difference for unswept wings are very noticeable, for example, for P-51 only 80-75% of the low Mach CLmax remains at 0.5-0.6M. P-51 airfoil is very special - it has no constant CLmax drop with Mach number, but other conventional airfoils for P-39, F-6F, etc have very sufficient CLmax drop up to half of initial. At high altitude this effect is even more noticeable because of low EAS, high TAS and lower speed of sound. For GA planes with low Vne/Vstall ratio this 1 g stall approach is widely used without significant errors, but it is unsuitable for high-performance fighters.
Nope. Not only is this not a critical thing, within the context of a discussion on WW2 airplanes it just doesn't matter. AFNA starting on page 176 beats this topic to death and their formulas don't include CLmax and they have specific examples out to 500 knots, way beyond the speed for any WW2 plane in a turn fight. Now they do talk about this factor in transsonic and supersonic flight, but that's way outside the scope of this discussion. cont: Also, PHOAK has this covered in Chapter 5, page 5-39 specifically. These are the two most peer reviewed publications in aviation and they both cover this topic very well.
@@GregsAirplanesandAutomobiles Nope. CLmax is a critical parameter because it determines maximal lift, the plane can provide at the certain EAS and Mach. Anyway, the last word obviously is for NACA. Take a look, for example at post-war NACA-TN-1044 (1946) where high-speed wind tunnel and flight tests data are compared for several planes. Or, just for P-51D, NACA - RM-L6110 (June 1947). This report is based on flight tests as well.
@@Kelvin3531 You are correct. CLmax is critical. For these discussions CLmax, V and bank angle are key, but even more important is that T=D & L =W (where L is the normal Lift Vector opposing W} for constant altitude turns. Solving for V=min, G=max requires checking against equilibrium.
The P-51 all day long. If it's flown by the right pilot. Richard Candaleria, and some other notable aces could literally "spin" the plane around on a dime by throttling back, while pulling up hard, while kicking the rudder right, or left, positioning the Mustang on the flanks of the pursuing enemy aircraft as it passes by.
@@GregsAirplanesandAutomobiles Hans Joachim Marseilles (158 kills) could throw his 109F around ,lowering flaps slats and even undercarriage (gear) to turn inside Alied fighters and drop through the defensive "Lufbery ring" formations , often scoring several kills in one pass. The trouble with the 109`s was that you could pull the wings off them ! the aircraft gave no warning when limits were close ,,the Spit would shudder and let you know to ease off.It was down to the nerve of the German pilot how far he DARED to go.The pilot could cope with higher "G"in the Messerschmitt due to the "recumbent"seating position.
"Pilots and flight engineers love charts." This old Pave Low FE heard that! If it came down to throwing out my PJs or charts, I'd sleep easy knowing PJs love jumping out of stuff anyways.
Very informative video. What you must remember is that air superiority is a contest between complete air combat systems. You need to compare all aspects of the machines and weapons as well as pilot training and logistics support. Pilot training is also crucial and the Allies, especially the US had the ability to rotate skilled combat pilots back as instructors and also to give the pilots the necessary hours to be far more skilled than new Axis pilots. Also, remember that the US bombers while suffering horrible loses also inflicted massive losses on the German fighters. And the Allied offensives against German fuel resources greatly cut the ability of Germany in their attempts to train new pilots. It is even necessary to consider cultures, with the US men's experience bird hunting with shotguns they were ideally suited to learning high deflection shooting. Also, the men from the US had far more experience repairing engines since the farm equipment and far more cars in the US meant there was a ready supply of experienced mechanics. And then there are just the fortunes of fate with the US having the M2 Browning .50 calibre which was by far the best air to air weapon of the war. While it was not the heaviest calibre its flat trajectory and high cyclic rate meant it was probably the easiest air to air weapon to become proficient with and its varied ammo made it very effective against German planes without self-sealing fuel tanks when firing incendiary rounds. While the Germans produced large numbers of aircraft they simply had no hope of matching the US war production with the US outproducing the rest of the world by large margins of aeroplanes and virtually all other weapons. The US also trained the Russians on mass production so they could also produce a large number of tanks and planes as well. Had the Army Air Corp adopted the Pacific Naval aviation training for aviation marksmanship the Allies would have really devastated the German Air Force. The Pacific Naval Aviators were by far the best trained and best marksman of the world's aviators during the war. The Naval Aviators often practised marksmanship every other day when cruising with two carriers. One carrier provided CAP and sub patrols while the other practised high deflection shooting with towed targets and then alternated the next day. The Pacific aviators were the first to jury-rig deflection sights from Army bombers to aid them in high deflection shooting.
I don't disagree with any of that, but I can't fit all those discussions into a 20min video. I do cover some of those subjects to a small extent in other videos. Bottom line is that this is more of technical channel, so I don't really want to make a video on pilot training specifically. Thanks for your post, and again, I don't disagree with the importance of pilot training.
I doubt you are interested in my references. But ask yourself what are the pluses and minuses of the 20 mm air to air vs the pluses and minuses of the .50 cal.
18tangles, If you were surprised by my reference to bird hunting I must tell you that you are missing a lot of information on WW 2 aerial combat. This is a reference that many historical references include. You might want to do a good bit more reading if you really would like to better understand air combat during WW 2, but it seems that you feel like you are already the expert.
I think the first plane you showed may be a P-51A or an early variant. There's an early one on display at EAA here in Wisconsin before the bubble canopy was added. Either way, I love your channel.
That's fascinating. I can't believe many Navy fighters were ever flown to Angels 30, since they didn't escort many B-29s, and few Japanese planes could reach such a high altitude.
I agree, plane version and pilot skill are very important factors on top of physics. Put Erich Hartman in a 109-K and he's probably outturning every P51 on the planet. Put a rookie in a 109-E and he's probably outturned by every P51 on the planet..
Ive seen P51s pulling 16 second turns for a second or two in other sims... but in WT its certainly NOT a turner, however, at a decent speed, it really can turn!
Everyone knows those History Channel dogfight tv series. I remember the story of a long, climbing diving contest involving a Corsair. A technical analysis and explanation behind this kind of story would be interesting to hear.
Like you said, power plays a big role here. And thus it depends entirely on which 109 variant and which engine setting the P-51 was running at. The P-51D before June 1944 was limited to only 67"Hg M.P. which equated to about 1630HP at takeoff. However after June 1944 it was cleared for 75"Hg and thus had about 1860HP at takeoff. A Mustang running this setting would out-turn any Gustav or Kurfurst 109, while being still being out-turned by the earlier 109F and E. Of course, this isn't taking into account fuel loads. The P-51Ds often faced 109s with lots of fuel loaded up, so that might have evened the playing field more.
Wow, I almost fell out of my chair when I saw someone commented on this video. Analytics show that this is by far my least popular video. Almost nobody has watched the whole thing. I guess calculating turn performance is much too technical even for this channel, which is why I am tending to focus more on engine stuff. That's what people seem to like, or at least my subscribers. Anyway, yes, at 75" and at certain altitudes, and of course depending on load, the P51 will have an advantage in sustained turn rates. However I have no plans to make a video about sustained turn rates of WW2 fighters since there seems to be almost zero interest in it.
I'm watching a load of videos recently to try to get my head around the relative capabilities of WW2 aircraft. After watching the "Dogfights" programme on the History channel, then trawling through a bunch of YT videos, and the arguments in the comments sections, it seems to be a case of "the more I learn, the more I realise I don't know." I may be in a very small minority, but I for one would be very interested to watch a video giving details of the turn rates of various WW2 aircraft!
I'm sorry to hear that. Now I'll never find out how the airplane I wanted to fly in WW 2, the P-47, would have compared in turning performance to it's adversaries. I'm one of the nobodies that watched it all the way through.@@GregsAirplanesandAutomobiles
I did the calculation and turn radius as a function of speed, if without any structural limit, asymptotally approaches a value from above, that value being stall speed squared over g.
Greg's Airplanes and Automobiles radius of maximum performance turn equals speed squared over (g times the square root of (v/vs)^4-1), vs being stall speed
The -1 compensates for the amount of lift spent in counteracting gravity instead of contributing to the turn. My calculation indicates that if without gravity, the airplane’s radius of maximum performance turn is constant disregarding of the speed.
This is what I use: www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/07_phak_ch5.pdf The math for this is on page 5-39. I would be curious to see if it comes out the same as your formula, I don't have time to do it right now because I am uploading a new video at this moment.
Sustained turn performance generally refers to turning at equilibrium: that is when the aircraft is not losing speed or altitude. If the P-51 were to have superior sustained turn performance that would be because it has more available engine power and wings with a higher CL/CD at the required CL (and thus angle of attack) for max g's. You cannot get sustained turn performance from only the numbers you used.
We didn't cover sustained turn performance in this video. I specifically said that in the video. I cover that in another video. In fact, I think I beat it to death in my P-47 pt. 5 video.
@@GregsAirplanesandAutomobiles Yes this only addresses the comment made right before at 12:24 which seems to imply that "more speed to lose" is related to sustained turn performance.
I understand. What I meant there is that the 51 would be able to maintain a higher average rate for some period of time because of the extra speed. That's not the same as sustained turn performance, but I see how it could have been viewed that way. I think you will like this video: th-cam.com/video/KahHLtYlveQ/w-d-xo.html
Love your video series, but I respectfully disagree with the idea that the mass of a plane doesn’t affect its turn performance. To turn an airplane (or anything else), you have to provide a lateral force to overcome the plane's linear momentum, which is its mass times its velocity. Obviously, it takes more force to change the momentum of a heavy object, than it does a light one. For an example, consider the centripetal force required to hold a plane in a circular turn. The equation for turn radius that you cite in the video is for a spiral, but the equations for a circle are better known, and the math is simpler, so I'm using it for my example. However, you can derive similar equations for a spiral, and get basically the same result. As is well known, the centripetal force required to hold an object in a circular turn is...
F = m * V-squared / R ...where m = mass, V = tangential velocity, and R = turning radius. In an airplane, the centripetal force provided primarily comes from the lift of the wings, times the sine of the bank angle. Again, as is well known, the equation for lift is...
L = F = ρ * Cd * A * V-squared ...where ρ = air density, Cd = Coefficient of Lift, A = wing area, and V = tangential velocity. When the centripetal force required = centripetal force provided, the velocity-squared terms cancel out. Rearrange the equations, and the circular turn radius is...
R = m / [sine theta * ρ * Cd * A] ...where theta = the bank angle. In other words, a sustained turn radius is proportional to the mass of the airplane, but inversely proportional to the bank angle, air density, and the lifting characteristics of the wings (and/or other lifting surfaces). At that point, speed no longer is a factor, so long as it's high enough to prevent stalling. Why isn't airplane mass mentioned in the pilot's manual? My experience with operating manuals is that usually, they only address factors that the operator can control. Unless you count jettisoning fuel or stores, there isn't much a pilot can do about mass.
Take any airplane, but in this case, I'll use a 767. At 250,000 pounds, when at 250 knots in a 30 degree bank, the turn radius will be identical when at 350,000 pounds at 250 knots with 30 degrees of bank. Airplane manuals certainly do address mass, in the case of the 767-300 it could be flying at a weight anywhere between about 180,000 pounds, and 412,000 pounds. The manual has to address that as take off and landing distances will vary hugely, as will service ceiling. Now, your math isn't wrong, it's just that you are doing the wrong math problem. There will be further explanation of this concept in my next video, so rather than type several paragraphs here, I'll just get to work on that.
@@GregsAirplanesandAutomobiles - Hi, Greg - Prior to entering the turn, the heavier plane already will have been trimmed to give it an effectively larger coefficient of lift, leaving speed and bank angle as the two remaining variables determining its turn radius. It should be noted that the equation given for turn radius describes a spiral, suggesting the assumption of enough reserve wing loading to tighten the turn, so it's not at all surprising that, initially, at least, disparate airplanes, flying at the same speed and bank angle, will share a common radius (though probably not turn rate). My point is, that there's a limiting turn radius for which mass will be the dominant factor. Put another way, if - Lord help us - two 767s were to get into a dogfight, my money would be on the lighter of the two.
Chuckling...The British are here in the comments section blathering on about the spitfire this and that. Didn't see it in title, but, here they are! Again! Ridiculous! Ancient history pal, WHAT HAVE YOU DONE LATELY?
Overall, the British people are quite supportive of this channel. The youtube analytics show that. There are a few who seem to think the Spitfire was the most important plane of the war. It's my opinion that they are worshiping the wrong British plane, and there are other British planes that were of much greater significance to the war effort. Once I get the videos done covering basic engine and aerodynamic principles, then I'll start going more deeply into specific planes, and we will be discussing the Spitfire.
The interesting thing is that for instantaneous min radius, we don't *really* care about speed at all. It (very nearly) drops out of the equation in this regime. Let k = 1/2 C_L A rho. Any given wing has a fixed reference area and maximum lift coefficient. Rho is air density and is roughly a function of altitude. Then maximum lift L = k v^2 R = v^2/a = mv^2/L = m/k = v_stall^2/g The notable approximation is that this a = L/m isn't *quite* right for a level turn... it assume you bank straight sideways and god be darned if you lose some altitude. The more accurate expression is to correct it by the factor sqrt(1-1/g_factor^2). For a 7g level turn this is sqrt(1-1/7^2) ~ sqrt(1-1/50) ~ 1-1/100 = .99. If you are flying a bit slower at sea level and can only pull 4 g level it's about .97. Your turn radius will only be 2% more. So we see that as long as you're broadly near the right speed, your turn radius is fairly insensitive to it. What matters operationally is reaching C_L_max, which in practice means pulling to just before the stall AoA. It also becomes obvious that flaps always tighten your turn instantaneously (since they increase lift/decrease stall speed) The reason why the plane needs so much farther to turn at altitude is air density. Turn radius is inversely proportional to air density, and 30,000 ft air is 3/10 as dense as at sea level, so the turn radius should be 10/3 times that at sea level. This is not very dependant on speed... even if you were able to go fast enough to pull 7g you would only decrease radius by 2% or so. Which is why you can also say that roughly speaking, the relative turn performance of fighters is not a function of altitude in any condition where turn fighting is possible. If both fighters can pull more than 3 g or so then the one that turns tighter at sea level will still turn tighter at altitude, and by about the same amount. Only if you're in a condition where one fighter is near its ceiling and the other is not will there be a major change in this ratio.
According to Aerodynamics for Naval Aviators, maximum turn performance happens at the lowest speed at which the plane can pull it's maximum allowed G load, thus speed is a factor. Power is a factor in sustained turns at a constant altitude.
Like Erich Hartmann said, you cannot say this or that Airplane was better. It really depended what Pilot sat in them. And I heard that the ME 109 K4 was faster than the P-51. But I cannot really confirm if this is the case.
I want to do that. Actually I sort of did with my Sopwith Camel vs. DR1 turn rate video, but it's not particularly scientific, more of a tutorial on a specific flight sim. I'll do a more complete video on this subject in the future.
Very interesting stuff. One thing that has me thinking would be more powerplant changes in aircraft. What made the Mustang the Mustang was the Spit's engine. It turned it from a decent aircraft into a high altitude beast that was also pretty fuel miserly and just very good overall in a fight. I would think there'd be no way for a Mustang to outturn a Spit due to Spit's near glider like wings. Both those wings, the Mustang's and the Spitfire's may be the most famous fighter wing designs of the war. One is as thin as it can be but is still deep because it holds a 20mm cannon. The other embraces laminar flow design that had its own neat effects. All of that gets a person to wondering what some aircraft would be like with the engine of another. Can you imagine a snub-nosed Mustang or Spit with a PW R-2800?
John R A radial Mustang would largely fail, imo. The mustang was designed by a former racer, and as such, placed massive importance on low frontal area. Also, a lot of the drag reduction on the mustang was from the redesigned cooling system, which would have been useless with an air cooled engine.
Yeah, it'd be interesting to see and would also pick up significant drag as you stated. Radial fighters had that "jug" look which was one of the P-47's nicknames whereas a V-engine helps contribute to that sleek narrower look that we associate with the 'Stang, Spit, and Bf-109. Those 3 are among the most beautiful aircraft of the war.
Can you make a video about P51d disadvantages. Everybody talking only about P51d superiority, but there is got to be also some bad things. Could this aircraft compete with germans fighter in low/mid atitudes? Wasnt P51d also very vulnerable if it was hit in belly, because it didnt have strong protection?...
I feel like I have covered that in my P-47 series, and in my P-51 vs. Dora video. The P-51 was awesome, but not all conquering, a skilled pilot in a G-14 or a Dora will give it a tough time. I guess I could make a video on the specifics.
@@GregsAirplanesandAutomobiles Thank you for a quick response. Will check P-47 series. Have not watch this series yet. Anyway, these your videos are just masterpieces! :D
In the BoB the Hurricane also out turned the Spit. Of course the spit was continually developed as a fighter whereas the hurricane wasn't, but in 1940 the hurricane was probably the more effective of the two. It wasn't as pretty tho so the ugly one got ignored a bit. Many pilots tho expressed a preference for the hurricane, Bader included.
![The Aircraft That Conquered The Atlantic | Vickers Vimy [Aircraft Overview #29]](http://i.ytimg.com/vi/h6WC2l48BDU/mqdefault.jpg)
Retired flight instructor, CPA. As I was watching your videos, I knew only a pilot could have your understanding, at the end of this video you gave it away you had this knowledge, I like your quick and fast definite way of getting your point across. THANKS.
I wish the War Thunder developers would spend some time watching your videos. Good stuff.
IL-2 is way better, not perfect, but better.
@@DrJohn493 what about dcs?
@@anneallison6402 DCS too. Compared to IL-2, it's junk
@@DrJohn493 really so Il2 is the best I guess, DCS looks nicer tho. I find war thunder too unrealistic but it kinda gives you an idea
There is a much better game for dogfighting, Aces High. There planes are modeled really well.
Not sure how many of you noticed, but turn rate varies greatly by speed and altitude. In short just about any plane in WW2 if jumped, the enemy plane was usually in a dive carrying extra speed from the dive, could out turn the enemy by the simple fact your speed is lower. The faster plan could not turn with you. Then the turn radius between different aircraft types all had a best altitude at which it could turn faster than at any other altitude. However no two aircraft shared this same altitude. Means at altitude X airplane Y could outturn airplane Z at same airspeed, but change the altitude and airplane Z could likely outturn airplane Y at same speed. You wanted to fight at the altitude that your plane had the advantage. WW2 flight sims do not model this at all. I add this in because most people only experience with flying is in a flight sim. And you need to know the flight sims are not very accurate as compared to real life flying.
I am glad you paid so much attention in this video. Everything you said is correct, and your are right about flight sims.
Something my father (a military pilot from the WWII era) said that is pretty obvious is that a turning plane is easier to catch up with. Like a triangle, the turning pilot is flying the adjacent and then opposite leg while the pursuing pilot is flying the hypotenuse - a shorter distance and closing giving a good chance to connect with a deflection shot.
Well said, dan.
Your vids begin to answer many questions that have hung up discussions "forever". On top of that, you relate things in concrete terms us laymen can grasp that otherwise might have remained mystical. I'm not a pilot, more historian, but history is rife with technology and tech solutions. Love it! "Speed and bank angle"!
Can't thank you enough.
Thanks Jeff. I consider this one to be my best video, but it's the least popular. It makes me happy to see that some people like it. I think the concepts are easy to understand once you know the key factors, and simply plot them on the chart.
Can't wait to get into sustained turn rates. I'm amazed that I've read about WW2 plane performance for years without someone laying this stuff out. As you say its just key factors and charts or algebra, but if no one around you knows how to solve a triangle, you just imagine that perhaps there are special people who can. Not very satisfying.
Well done, as usual. I'm neither pilot nor engineer, but find this stuff fascinating because my Dad was a Navy pilot in WW 2 (46 missions in an F6F off the Lexington in 1944 with VF-19, then rotated back home for a transition to the F4U-4 and 9 months of training with VBF-150 until war's end), then a test pilot with McDonnell Aircraft postwar (XF-85, XF-88, F2H, etc.). I'd love to see a similar comparison of those two very successful WW 2 Navy fighters vs. the Zero, the Ki-44 ("Tojo"), or the Ki-84 ("Frank"). Carrier warfare made very different demands on an airframe, pilot and engine than did the higher-altitude fighting more common in Europe.
Hi Ray, thanks for your post. I'll cover those subjects in great detail.
My RAAF 77 Squadron Technical Officer had flown P51 Mustangs during the Korean War. He told me they would lose in practice 1v1 against RNZAF Corsairs because the Corsair could sustain turn ' energy ' better. Mustang is an energy fighter better suited to ' shoot and scoot ' rather than ' turn and burn '
Mustang was boom and zoom not energy fighting like the Bf-109
@@princesofthepower3690 Bf-109 was the original energy fighter... sitting up high, then peck and zoom.
The presentation that separates the aviator men from the video game fan boys! Aerodynamics for Naval Aviators was handed to us first day at Pensacola! Thanks.
there are a number of people who are both and a number of those who play flight sims and games that research carefully and look through information such as this in order to fact check the games and sims they play. That is a pointless put-down.
please do not stereotype us mate
Actually not really. I think what he's trying to say is, what the stats say about an aircraft (especially a ww2 aircraft) on paper, is by no means exactly how said aircraft will perform in the air. Plus there are far more things to be taken into consideration that a video game or simulator just cant account for or reproduce. Anyone who has actually flown one of these planes will attest to that.
lol man you declines the physics
War Thunder has taught me how to land a b25 lol
These videos remain the Gold Standard.
haha....got me... I had to rewind to take another look.. A36 Apache ground attack aircraft. I remember this one from reading up on the Mustang history in William N Hess's P51 Bomber Escort book.
Good job Racer X, it's easy to miss the details. I stood in front that plane for at least 30 seconds before I noticed it wasn't a Mustang ;)
Many people called the A-36 a Mustang, also known as an Apache and Invader.
Fantastic Reference, Aerodynamics for Naval Aviators is a hidden gem.
The P-51’s first notch of flaps can be employed up to ~400 mph, but it seems that the 109’s flaps are more effective when used below the activation speed limit which is > 200 mph.
So many factors in performance and dogfighting I never even considered! And it brings to light what a true high performance aircraft would of had to he able to do back then to really hold a helpful advantage.
This is a remarkable piece of work. Well articulated and very substantial. I learn a ton from this posting. Thanks for the effort and work.
this reminds me of the book i read about john 40 sec boyd and his energy management theory and how it applied to fighters. well done sir.
OH, I have a video about Boyd.
@@GregsAirplanesandAutomobiles I just rewatched your video about Boyd. I have read his biography before. I would love to hear more about this and how he helped build the F-16 and other Fighters
I recently got a request for a 109 vs P51 turn radius analysis. I'll do that in the next couple weeks, along with a DR1 vs. Camel in Rise of Flight analysis.
I will be waiting !. One thing about engines ........ I have always been interested in Junkers Jumo 213 . It powered the FW -190 D and TA152.
It would be interesting to see how it stacked up compared to Daimler 605 and RR Packard. That said --I really like your videos , most pilots ( not video gamers ) have to love them . Thank you ! .
Note that the P-51 Pilot Manual specifies 20 degrees of wing flap extension for a minimum radius and max sustained rate turn.
What's wrong with video gamers? I love his videos too...
lol , it's far simpler, P-51 had significantly bigger wing area than Bf-109 and that matters a lot, especially at higher altitudes
Also the wing design itself, laminar flow wings on the P51 are made for high alt. They give the pony advantage. Lower the advantage slightly to the 109.
Interesting subject. After watching a video of a Wildcat flying a vertical S, I decided to try it in my Extra 330LC. It gets even more intricate when you consider the dynamics of changing gravitational effect in a vertical S. The Wildcat stacked a half loop on top of an Immelmann. In the Extra, it is possible to stack two Immelmanns (only just). I determined that an Immelmann is possible if you start at 100 KIAS, but you are very low on energy in the roll-off-the-top (around 40 KIAS, unloaded, but with significant torque and propeller slipstream effects due to the low speed and loss of aileron effectiveness). You cannot pull more than 2.5g on the entry, or you will enter an accelerated stall that will rob energy and make it impossible to continue. This means the first (lower) Immelmann must leave you with at least 100 KIAS on its exit to facilitate an immediate second Immelmann. It can be achieved by starting the first Immelmann at around 175-185 KIAS and pulling around 6-7g initially. This will leave 100-120 KIAS available at the start of the second Immelmann. Now to figure out the optimum g to maximize energy retention and attempt to improve the symmetry of the figure (since the top Immelmann is much slower, but occurs at significantly lower g, it is hard to estimate the radius of turn for each). 1g stall in my Extra comes at around 63 KIAS (two up), so 185 KIAS will accommodate an instantaneous 8.5g. G-limit two up is +/-8g, but solo it goes up to +/-10g. I estimate that solo I can run about 15% lighter, which should improve the vertical performance, although inertia may actually be beneficial in the initial “zoom.” The difficulty is optimizing g-loading to maximize performance (high g means you turn tighter (initially), but it significantly increases induced drag and robs energy). A tighter turn radius also reduces the time you spend fighting the Earth’s gravity opposing your thrust. All the quantities are continuously varying, making for some very complicated physics.
Two immelmanns in a row would be quite impressive to see. It makes sense that a really well flown Extra could do it, but I don't recall ever seeing it done.
@@GregsAirplanesandAutomobiles it really consumes the available energy. The second half-roll at the very top (roll to the left) becomes a torque roll at 40 KIAS, so aileron must be centered about 45° early to finish upright with wings level (the torque wants to keep the roll going). It’s also a challenge to keep the whole S in a single plane (i.e. to avoid twisting off plane, especially on the second Immelmann).
And a lot of the difference in performance can be attributed to the regime in which the plane was intended to fight. The NACA Roll rates at speed chart helps with this (as you already know).
I'm very sorry that I saw only now this very interesting video regarding the comparative speed, angle of attack and other factors versus other airplanes including of course the Me 109! Thanks for enlightening me and I will look forward to to see more of your videos! Thanks!!
An additional factor is pitch trim, Airfoils have a (generally) nose down pitching moment that is balanced by the horizontal tail. The tail load is adds to the load already born by the wing as it pulls the plane thru the turn... more induced drag.
The Mustang’s airfoil has appreciable pitching moment; the Wildcat’s NACA 23015 has nil.
The NACA 230xx series nil pitching moment meant the pilot could throw the plane around without having to trim. The 230xx was used on the Wildcat, Hellcat, Bearcat, Corsair, Lightning, FW190 and Beech Bonanza... it’s been around. Downsides is bad stall, drag, and won’t carry ice.
Centre of mass also affects the amount of control surface movement needed to change direction, and hence the induced drag from the tail feathers ! Bearcat was almost unflyable if you could not see the horizon, not safe at night... !!
First off, thanks for the links Greg! I’ve got a PDF copy of the navy book on my iPad now!
After a second look, it was an A36 Apache. Nice! And I’ve been there to see that in person.
I just learned something.
When he said is was not a mustang i was already suspecting that this was an Apache.
But I started reading the wiki entry and I always thought that the A36 predated the mustang but not that what I found out. Amazing plane with amazing missons.
Please by all means quote Clarence Anderson, Colonel Bud is a one and only. I hope that one day they declassify his wild weasel strategies and let us see the camera footage. I just poured a shot of Old Crow.
Greg, I really love your videos, because you make the complicated understandable.
I'd like to see the second part of this subject on sustained turn performance. And a third one that lists the various turn rates both instantaneous ans sustained at various speeds and altitudes, for all the major aircraft types in use in WW-II, but I think that is probably too much to ask? As all ways, I love your stuff.
Actually I have quite a bit of that, my 262 vs. P80 video has it and so does my P-47 part 5 video.
I love the pace, information, topics, etc.! Your videos ROCK!
Ehhh, forgive the unfortunate choice of words.
:)
Have you ever looked at P-51 V Navy F-6-F...though it seems like there are many variables...excellent videos.
There are many WWII vets who talk about out-turning an ME-109 under the right circumstances - altitude, speed, etc. Often they would drop some flaps that that would enable them to turn inside the ME-109
I watched a video of a Fw 190 ace talking about his experiences dogfighting Mustangs. He basically said that the P-51 had a very strong initial turn, to the point where it would come up behind the six of the German plane, and a lot of novice German pilots lost the nerves and tried to dive away or break off. Which, in most cases was their demise, since you won't outdive a P-51 in a German fighter.
He then continued that, if you kept turning with the Mustang, you would eventually catch it again and apparently a lot of the older experienced German veterans knew about this and thus didn't try to break away or dive.
Now a 190 is of course different to a 109 but I still thought it was quite interesting.
The name of the ace was Willi Reschke.
@@TheSerec
That may be true of the BF-109, but a FW-190 will handily out dive anything but a P-47, and isn't really suited to turn against anything. Its roll rate is fantastic, but it bleeds energy like a stuck pig in any but the most gentle turns.
Surprising revelations, well done.
The FM-2 vs. P-51 comparisons are really cool. Where else but on Greg's channel would you see that?
Great videos! I had to laugh when you mentioned one plane absolutely out-turning the other "and vice-versa". Years ago I read a commentary on Zeroes and P-40s. It may have been Murray Rubenstein's excellent comparison series, but I really don't remember for sure. What I do recall is reading a quote from a P-40 pilot to the effect that "I never met a Zero that could out-turn me." Given that pretty much everyone agrees that the Zero was by far the better turner, I learned a little bit about how much perceptions play a part in what we see. If a P-40 pilot takes a shot from 300 yards behind a Zero and the Japanese pilot throws it into a tight turn in an attempt to avoid another shot, the American only has to turn a few degrees to keep him in his sights. Sure, the shot's going to be a much worse deflection shot, but as far the shooter is concerned the Zero is still in front of his guns and it sure looks to him like he easily out-turned his target.
Of course personal experience is one of the worst judges of facts, but I can see where a lot of these stories get their start.
"I never met a Zero that could out-turn me."
This might be the phenomenon called "survivorship bias" - none of the pilots that were out-turned by Zeroes lived to tell the tale.
sebrafield wtf, now the zero is outterned by p40. Ok I understand american pilots had to lie some to win any medal and be a bit famous I mean profits for them. But why you fall in it!?
@@geldoncupi1 did you really not read the entire comment he wrote?
The zero was very good at low speed turns. P-40 Pilots learned to keep the air speed up. In high speed turns the zero's controls became very heavy, if it slowed down to make the turn it gave a speed advantage to the P-40, then could not acceleruate fast enough(due to radial engine drag) to escape the P-40's speed advantage.
@@geldoncupi1 the zero couldn't turn well at all at speed
I've read other places that the turn performance of a P-61 was better than any other fighter of WWII. I haven't watched much of the video above but it sounds like you're concentrating on those 2 aircraft. I was hoping for a more widespread comparison of various craft in a typical war time load for comparison.
I watched a Navy F-14 at the Point Mugu Space Fair (their name for their annual air show) do a full 360 degree turn while about 250 feet above sea level within the confines of the base between the outer fence and the runway closest to that fence, where the pilot basically stood the plane at nearly 90 degrees from horizontal and flew that circle and I could hear the jockeying of the throttle and see the shifts in the control surfaces as he flew the circle. I doubt seriously if any WWII fighter could have matched that circle under any circumstances. That pilot certainly earned his pay that day.
I saw the same display at Pt. Mugu. It was impressive. I also saw the Blue Angels there when the flew the F4!
It should be noted that RAF and RN Spitfire/Seafire pilots used the Franks water filled G-suit as early as 1942. I've read that they exceeded the structural limits of the Seafire and returned with bent and wrinkled wings. That was Op Torch, so I'll assume it was low level combat.
Very good commentary on warbirds. Not borring at all. Keep them coming.
Thanks, I do think this one is my most boring video, but there was no exciting way to convey this information.
I absolutely love your meticulous research and data presentation, looking forward to a P-51 vs. 109 turn radius analysis video (and maybe add a spitfire too for reference?) looking forward to your upcoming videos.
Thank you. I'll focus in some turning radius videos, but first I need to cover some other things.
yes, love to see how the Mustang compare to the Spitfire!!
The first "Mustang" image was an A-36 Apache dive bomber.
Awesome video and funny at moments...such as at 2:08 where you stated that our parents had paid for that book long ago...awesome!
Thanks very much. I consider this to be my best video. It sat for about 6 months with only a couple dozen views. I had actually decided not to focus on airframe issues in videos because this video seemed to be such a failure in terms of views. I am glad to see that it's now doing well, and a lot of people like it.
The A36 was a Mustang optimized for ground attack.
That Allison V-1710 with it's above-spinner intake. A great plane in its own right!
Your videos keep popping up as recommended for me to view by TH-cam. . . I guess I'll have to subscribe. I enjoy what I've seen thus far. :-)
Excellent video, A+ for content. Narration was professional. Thank you
Oh, thank you!
I would like to see a video comparing specs on the p51b & c models to the p51d. Most people don't even know these older models exist. Great video!!
B and C were essentially the same, built at different factories (like the D and the K were essentially the same). The B and C were lighter than the D, the D had the bubble canopy (of course), a thicker wing (which allowed the guns to be mounted upright and alleviated some problems with jamming in the B and C). The heavier weight also made the D slightly slower, as did the bubble canopy (it's actually got more drag than the faired-in birdcage canopy and high turtledeck). IIRC the B and C were usually only fitted with 4 .50 machine guns, the D had 6 (adding to the weight). The D came in quite late, supposedly fully half of the Mustangs in operation in Europe on VE day were still Bs and Cs.
I've read in several articles that a 4-engined Short Stirling bomber could and did out-turn a Bf109. I find that a bit incredible (in correct parlance, not modern parlance).
Hmm, I won't say it couldn't have happened. If the Stirling was as a lower speed, and the 109 was way too fast, then maybe, or if the 109 was way too slow, or damaged, again, it could happen, but in any apples to apples comparison, or a sustained turn the 109 will easily out turn the Stirling.
It's to do with wing loading. Convair B36 was capable of out-turning contemporary jet fighters at high altitude.
This month's Flight Journal has an informative article on the A36 Apache.
This is super interesting video. Also that plane in the beginning, I thought it looked weird to be P51 but thought I was mistaken lol I can't really pinpoint any differences but it looks odd to me(and yeah after reading the comments I found out it was A36)
The A36 is actually the first Mustang with an Allison engine
You mentioned doing a P-51 vs. turn FW-190D comparative. PLEASE DO THIS!! The world has an aching need to know.
I am doing it, but the video has grown far beyond a turn comparison.
And that's a GOOD thing! Was hoping for more than a treatise on turn performance between these two warbirds (may two favorties of all time) Thanks in advance! : D
With the laminar flow wing the p-51s maneuverability was improved at around 400 kmh. And was a brick at lower speeds. The saber had the same issue so that’s another factor it reduced turbulence on the wings when turning allowing to to maintain speed. And be able to pull tight turns where any other design (like the 109) would loose manuevering performance due to turbulence on the wing root this is unique to the p-51 and what made it so futuristic. I just wanted to contribute this
laminar flow wasnt archived due to distortion of airflow from propeller and guns, also rivets. laminar flow was only archived in models. laminar wings produce much less drag at the cost of less lift, so it doesnt help maneuverbility.
laminar flow was only archived after war with specially prepared wing surfaces.
reason to use such airfoils is lower drag= higher speed, better fuel consumption, which is essential for a long range escort fighter.
Lemsko that’s not entirely true. The p-51s wings were thinner at wing root and tip it’s wings were specifically designed for high speed maneuvers. They played with many design. Mostly using math and theory. The p-51s wings are what makes it unique they were also used on saber which is noted as the cause of some of its landing issues The reduced turbulence meant it could hold energy better. And turn better against high amounts of speed. You don’t honestly think they just threw planes together back then because they didn’t have a wind tunnel and hope they worked?
they havnt archived laminar flow in real flight. the advantage vs conventional airfoils is the much lower drag they produce. i dont say it is bad, it was exceptional at that time compared to other planes.
take a short reading here:
wp1113056.server-he.de/ABL/20-forschung/laminarfluegel/laminarfluegel_en.htm
as i remember USA had no windtunnel capable of testing high speed, the results are from german windtunnel tests. After war they archived laminar flow with extra prepared wings, but not over whole wing, gun ports and propeller area couldnt produce laminar flow even with nearly perfect surface. Mustang is definitely a absolute great design for an efficiant low drag aircraft.
18tangles spitfire has eliptical wings. Not known for speed due to heavy drag but very maneuverable
Well done Thank you for posting.
Great video. I do believe that the "mustang" you first showed was an A-26 Apache.
36*
5:00 that explains a heck of a lot about the P-38 being so surprisingly agile, honestly. It was a poor sustained turner, but in the right conditions, it could hold with Zekes for a brief moment
absolutely.
Very good presentation sir!
Your content is awesome a pleasure to watch.
i live in belgium;, we use metric. i had to convert everything to metric. wich is pretty time consuming;, yet i foiund it an informative and fun video :) greetz from Belgium :)
Thanks Sean. In Belgium they use feet for altitude measurement and knots for airspeed. I fly over Belgium all the time, so I know. Linkage: www.eurocontrol.int/muac . However, I get that a lot of people like the metric system, so I'll include those numbers from now on.
The first North American aircraft was an A-36 Apache, the duve bomber conversion of the P-51 A.
Interesting video series. While the P51 mustang is my favorite aircraft of all time it's interesting to see a proper analysis to see how much what I know or think I know is just myth and bull shit. To be honest I think timing of the mustang introduction plays a huge part in it's success in Europe but to win air superiority over a foreign country is a huge victory. The germans out numbered the RAF 6:1 and lost the battle of Britain and they had airfields in France the Americans did it from England for the most part. Home ground advantage is a big force multiplier. I'll be watching your series to learn more. keep up the good work and thank you.
Corporal Punishment come on dude you really think the British had a fighter vs fighter kd of 6-1. They won the battle of Britian because the Germans had no need to win it. They wanted peace with the British. It was a waste of oil and resource to fight them.
Ryan, you might be one of like 12 people who know that the Germans were actually trying to get peace with the British. The historical political correctness revisionist police are going to show up at your door.
Interesting points , but consider a few facts The British where not short on planes due too a ramp up in production , it was experienced pilots that where the major problem , British tactics at the time where not too fight over France so the Germans mistakenly thought the RAF had fewer planes than they actually did. The Me-109 and Supermarine Spitfire and Hawker Hurricane where all short range point defense fighters , The Me-109 had 12 minutes of Endurance over London , Any German aircraft shot down where a total loss of an aircraft and captured crew if they bailed out , Where as the British if they survived just had a replacement aircraft. Its a 108 miles from London too Calais , and that is a long way too nurse a damaged aircraft low on fuel possibly leaking coolant and maybe Oil. The biggest problems the Germans ever faced where they never ever had enough fuel and what they did have was synthesized mostly from coal and was defiantly lower quality and Octane that the British had . Add to this most German pilots had been flying and fighting since 1939, some of these even carried on with little respite till 1945 truly remarkable really .
German's seeking peace? By peace you mean surrender. They were obviously intent on victory, a "peace" in the same sense that France was 'at peace' with Germany by then. Germany could have sought peace without initiating a bombing campaign. They let it go when they realized to their surprise that the Brits were not going to be easy like they had recently become accustomed to.
America could have been at peace with Japan and Germany simply by giving in and letting them run roughshod over the top of the nation. Just SURRENDER! How hard is THAT?? (tho some have noted that it would be a long futile fight with every other American civilian hiding behind a tree and picking off invading soldiers with hunting rifles regardless of Washington's policies--I like to think so)
If the Jews could do it over I guarantee they would NOT have "gone with the flow" they would have kept their guns and fought it out in the streets against the Nazi's, better to die fighting then be led defenseless to your death as a slave labor at best or in to a gas chamber. Same goes for the rest of us.
Bo McGillacutty Saying that Germany wanted peace with Great Britain is like saying Hitler wanted peace with Russia. Then Germany invaded Russia, I would not say Germany wanted peace with Great Britain but delay or stop it's further involvement like Sweden when Norway was invaded. Ultimately Germany attacked the UK so when people say Hitler wanted peace is a bit strange to me.
This is a great channel. Im only an Arm Chair pilot but I think comparing a p51 turn radius to a bf109's would be like comparing Ford Mustang super snake to a Lotus Exige S. you can Tell every bit of the Bf-109 was made for turning. Even Roll rate, Which I don't even think can be compared... x6 50.cal Machine guns plus amo hanging out in the wings, plus over 2,000 lbs heavier. As you said Turn rate may be close though. but if I think of roll rate+ turn rate +climb rate id say My money is on the bf-109.
I was talking to an old FM-2 pilot at an airshow years ago. He said that the FM-2 was way better than a wildcat. It had a lot more real world power and was very maneuverable. He said that they had no problem with zeros. In a turning fight he said the FM-2 could eat any other airplane alive
The FM-2 Wildcat is a really cool forgotten page of USN fighter history. A lot of people don't realize that the Wildcat stayed around after the Hellcat took over the main carriers.
It was an A36 in the start if the gun placement is still a dead give-away.
Good Job! Few people are able to pick that up.
Also the dive breaks
Ah. I didn't pick up on that. That thing was one mean dive bomber and attacker.
I have to say I don't know why the P-51 doesn't have the air brakes the A-36 has. They can be an assist in an aerial dogfight, by reducing the speed and causing an opponent to overshoot. However, you would have to be quick and smart to then use that to your advantage.
Alexander Hogan and you could use them like spoilers to help with roll rate or like a split rudder you see in the B2 Spirit to help in a turn.
Why does everyone forget about the P-38? The P-38 was the only WWII fighter with Fowler flaps that provided lower stall speed in addition to drag. With one notch of flaps, a P-38 J model had a power on stall speed below 60 knots. The aircraft had a notch on the flap level that allowed the pilot to ''slap' the flaps to this setting. This gave it the tightest turn radius of any American or European fighter. Only the Zeek and Oscar could out turn it. You don't hear about this much because American doctrine was boom and zoom rather than turn and burn.
You miss understanding. Turn radius and turn speed is two different things. You can turn tight but more important is speed turn.
I remember reading about one P-38 pilot who claimed that at low altitude he could outturn any plane, but it involved differential engine power and a pitch up - basically the P-38 could be going in the opposite direction faster than any other plane, changing direction 180 degrees.
Walter Eichhorn, a well known German pilot who flew the Messerschmitt "red 7" and participated in the filming of "Memphis Belle", later told me very much the same during a dinner. Furthermore in his opinion a Bf 109 G-10/K-4 was capable of outturning a P-51 D without difficulty (Eichhorn flew both types).
The K was about as numerous as the Me-262, there weren't enough of them to even consider. Might as well compare it to the P-51H, which would've outperformed ANY German propeller driven plane, in every aspect, during the war...
@@jamesbottger5894 it wouldn’t have outperformed a Ta-152H, Bf-019K14 or a Fw-190D13 with the EB engine in every aspect
@@princesofthepower3690 It absolutely would have. Also, there were so few of the 190D11, D13, and 109Ks produced, a Mustang pilot was about as likely to see a unicorn as they were seeing any of these planes...
So who do you believe, the German pilot, or American pilots who say they routinely out turned the German fighters?
Look at the performance specs, the P-51H was better in every way
I enjoy all you videos. Well done. PS, your Wright brothers stuff is great.
Hi Greg. Would it be a available for you to do a video on the reason for the different positions of the horizontal stab. Example, why are the P-51 and zero hor. stabs forward of where the F4F wildcats are. I would have thought the further back the horizontal Stabilizer and elevator, example, the F-22 Raptor, the more mechanical force generated to point the nose. Thanks again for your videos, love the educational value.
That's a complicated subject but I'll try to sum up.
1. For stability, you want the rudder as far aft of the CG as possible. Also, the farther aft it is, the smaller it can be and still provide adequate control and stability. So that's why you might want it as far back as you can get it.
2. For a fighter aircraft, you don't want it too stable. It needs to be able to maneuver quickly. A larger, more forward rudder can help this.
3. I suspect the main reason for a more forward rudder is structural. It puts a lot of torque on the fuselage and the fuselage is very small in cross section at the tail. Moving the rudder forward attaches it to the fuselage at a much stiffer and stronger point.
4. In cases where the rudder is actually behind the elevator, extreme elevator angles (say a tight turn) can disrupt the airflow to the rudder, reducing its effectiveness. Moving the rudder forward keeps it in cleaner air.
Thanks Greg, great presentations.
Thanks Dave
Thanks Greg!
Thank you for a great video. Not a pilot but I have flown and my most memorable experience was in a t-34 when we rolled 90, no back stick, and Dropped Like a Rock intentionally, no rudder, as to be expected. Is top rudder used in these high bank angle steep turns? Thanks.
Many P-38 pilots found that at lower altitudes in a turn against a 109 you add power to the up-wing engine, reduce power to the down-wing engine, and open the Fowler flaps about 10 degrees. You cut right inside of him where those 4 50 cals and single 20mm cannon cut him in half like a rip saw through balsa wood. Just ask Robin Olds. He loved his P-51 but understood the capabilities of his P-38 and pretty much every aircraft he flew. I think pilot skill is the best determining factor in turn radius.
If the two planes are equal in turn performance, then pilot skill will be the determining factor. The farther apart they are, the less it matters, For example, any Japanese pilot in a Zero in 1941 could out turn any US pilot in a Brewster Buffalo, and do it at any given speed.
Ah.. that "not a P-51" at the beginning of the video is the A-36 (officially "Apache") displayed at the Wright Patterson AFB museum at Dayton. I must've visited it 3 or 4 times over the years. The dive flaps are down and you can see the yellow identification stripe painted under (and I think over) the wings, because it resembled a Me-109 in the air. For those who haven't come across the A36 - it's the dive bomber version of what became the P-51, with the Allison V-1710. These were the first "Mustangs" used by the USAAF, mainly in Italy. Lots of people seem to have the opinion that the Allison Mustang was a lousy fighter - this is very far from the truth. It was faster than anything else available at the time on the deck, and the British made good use of it starting in late 1942. IIRC they only lost one to enemy fighters, while it was fully capable of engaging and shooting down Me-109s and FW-190s at the altitudes it was used at (mainly for rhubarbs and low level reconnaissance).
iskandartaib
I mean, not like the brits would have taken it over the kittyhawks they originally asked for if it was crummy, right? Not to mention the Rhubarb missions
mmmm.... Rhubarb
And also, the big incentive for improving its high altitude performance with a Merlin was that it was already known as a fast, superlative fighter with long range. If it was a lousy fighter they wouldn't have done it in the first place. (They did put Packard Merlins in the P-40 by the way - P40F/P40L - not sure if it was a one or two stage supercharged Merlin - but they didn't use them for high altitude long-range bomber escort.) I have the book published by Rolls Royce about the conversion (the "Mustang X") - it wasn't trivial. They had to re-route quite a bit of ducting and move components around to get the Merlin to fit.
The Wikipedia page says it did improve high altitude performance (the single stage Merlin was also used in the Spitfire V, which was used at high altitude) but it probably made no difference on the deck which is where they were mostly used (in North Africa).
iskandartaib The Merlin in the P40 did slightly increase the service ceiling but not much, and the Allison could NOT be beat at the lower altitudes !!! Did not change overall or total performance !!! And the Allison was easier to maintain !!!
Great vid, as usual. Thanks Greg.
One more point. Turn radius or pretty much any turn ability can be negated with the right tactics. Claire Chenault's P-40s were slower than Zeros, could not turn or climb with Zeros and they shot down scads of zeros by attacking from a higher altitude and zoomed through the Zero formation much faster than the zeros could dive and then continue their dive and pull a zoom climb out away from the conflict and return again from higher altitude to do it again, and again etc.
AVG didn’t face A6M’s.
They faced the similar looking Oscars. The Zero/Zeke were carrier aircraft.
Would you do a comparison of the Sabre and the Mig-15 turn radius?
Rate should be part of this title, discussion as well( it is later in the video) , as it isn't just turn radius, it's rate in terms of degrees per second which determine turn performance overall, many new flyers don't figure this out initially.
The single hardest thing when making these videos is somehow coming up with a title that makes everyone happy. I am not concerned about it because I am not going for clicks, I am going for content.
Fair enough, don't take this as negative criticism either, my point is only that so many pilots online in combat sims frequently don't understand that turn performance isn't just a matter of turn radius, and that rate plays just as important a roll, as do other factors. Which, again, I feel you explained very well in the video. I'm really enjoying your content, glad I found your channel, and I'll point others I fly with online here, some great videos. Plus I dig your small performance car vids, I've had a few Miatas and an Alfa 4C (and dozens of other performance cars). Please keep making content like this, the 109 stuff is especially great, been a 109 fan since I was a kid, and fly it in Aces High almost exclusively for the last 20 years online, and DCS and IL2's 109 models as well. My uncle built scale R/C models when I was a kid, and worked in that industry for years, and won a bunch of awards with his 109F4 model he built in the 80s (I have lots of pictures of this particular model). Ever since, I've read everything I could find on the 109, plus a neighbor my father had at his cabin was a German LW WW2 pilot, and was involved in the M163 project near the end of the war, and flew several models of 109. I wish I'd recorded all the conversations I'd had with him...
Can you do more on the engine and turn performance of the Zero?
I really should.
4:45 -- I feel like you and I are on the same metaphorical page at many points during this discussion. At the top of the video, you noted that there's two issues at hand: (a) minimum turning radius, and (b) maximum turning rate. And at that time, I said to myself -- that's not tough to keep separated! (A) will be a function of SPEED, whereas (B) will be a function of ACCELERATION (which we'll be calling thrust, or available power). Yay, high school physics and maths. :D
Also! I *LULZ* when you say "...assuming that this turn will be at a constant altitude." In my mind, that's the same as saying "....by keeping a constant Speed." Applying Thrust (ie. Acceleration) is the same as changing altitude, normally to go Up. It's a useful way to keep a constant altitude while co-ordinated turning, though.
Fascinating
Thanks, it's one of my less popular videos, but I am proud of it.
One critical thing was omitted in this video: maximal lift coefficient CLmax depends on Mach number, so, if it is derived from 1g stall speed with low Mach, it is not suitable to calculate high speed and high-g turn performance. The difference for unswept wings are very noticeable, for example, for P-51 only 80-75% of the low Mach CLmax remains at 0.5-0.6M. P-51 airfoil is very special - it has no constant CLmax drop with Mach number, but other conventional airfoils for P-39, F-6F, etc have very sufficient CLmax drop up to half of initial.
At high altitude this effect is even more noticeable because of low EAS, high TAS and lower speed of sound.
For GA planes with low Vne/Vstall ratio this 1 g stall approach is widely used without significant errors, but it is unsuitable for high-performance fighters.
Nope. Not only is this not a critical thing, within the context of a discussion on WW2 airplanes it just doesn't matter. AFNA starting on page 176 beats this topic to death and their formulas don't include CLmax and they have specific examples out to 500 knots, way beyond the speed for any WW2 plane in a turn fight. Now they do talk about this factor in transsonic and supersonic flight, but that's way outside the scope of this discussion. cont:
Also, PHOAK has this covered in Chapter 5, page 5-39 specifically. These are the two most peer reviewed publications in aviation and they both cover this topic very well.
@@GregsAirplanesandAutomobiles Nope. CLmax is a critical parameter because it determines maximal lift, the plane can provide at the certain EAS and Mach.
Anyway, the last word obviously is for NACA. Take a look, for example at post-war NACA-TN-1044 (1946) where high-speed wind tunnel and flight tests data are compared for several planes. Or, just for P-51D, NACA - RM-L6110 (June 1947). This report is based on flight tests as well.
@@Kelvin3531 You are correct. CLmax is critical. For these discussions CLmax, V and bank angle are key, but even more important is that T=D & L =W (where L is the normal Lift Vector opposing W} for constant altitude turns. Solving for V=min, G=max requires checking against equilibrium.
Any more on this topic? Cant believe i only saw it now. Was a good listen.
I have several more videos on this topic, watch my 262 vs. P-80 video or P-47 Thunderbolt maneuverability video.
@@GregsAirplanesandAutomobiles thanks mate, ill check them out for sure
The P-51 all day long. If it's flown by the right pilot. Richard Candaleria, and some other notable aces could literally "spin" the plane around on a dime by throttling back, while pulling up hard, while kicking the rudder right, or left, positioning the Mustang on the flanks of the pursuing enemy aircraft as it passes by.
The maneuver you describe is a snap roll, many WW2 fighters could do it.
@@GregsAirplanesandAutomobiles Hans Joachim Marseilles (158 kills) could throw his 109F around ,lowering flaps slats and even undercarriage (gear) to turn inside Alied fighters and drop through the defensive "Lufbery ring" formations , often scoring several kills in one pass. The trouble with the 109`s was that you could pull the wings off them ! the aircraft gave no warning when limits were close ,,the Spit would shudder and let you know to ease off.It was down to the nerve of the German pilot how far he DARED to go.The pilot could cope with higher "G"in the Messerschmitt due to the "recumbent"seating position.
"Pilots and flight engineers love charts."
This old Pave Low FE heard that! If it came down to throwing out my PJs or charts, I'd sleep easy knowing PJs love jumping out of stuff anyways.
Very informative video. What you must remember is that air superiority is a contest between complete air combat systems. You need to compare all aspects of the machines and weapons as well as pilot training and logistics support. Pilot training is also crucial and the Allies, especially the US had the ability to rotate skilled combat pilots back as instructors and also to give the pilots the necessary hours to be far more skilled than new Axis pilots. Also, remember that the US bombers while suffering horrible loses also inflicted massive losses on the German fighters. And the Allied offensives against German fuel resources greatly cut the ability of Germany in their attempts to train new pilots.
It is even necessary to consider cultures, with the US men's experience bird hunting with shotguns they were ideally suited to learning high deflection shooting. Also, the men from the US had far more experience repairing engines since the farm equipment and far more cars in the US meant there was a ready supply of experienced mechanics. And then there are just the fortunes of fate with the US having the M2 Browning .50 calibre which was by far the best air to air weapon of the war. While it was not the heaviest calibre its flat trajectory and high cyclic rate meant it was probably the easiest air to air weapon to become proficient with and its varied ammo made it very effective against German planes without self-sealing fuel tanks when firing incendiary rounds. While the Germans produced large numbers of aircraft they simply had no hope of matching the US war production with the US outproducing the rest of the world by large margins of aeroplanes and virtually all other weapons. The US also trained the Russians on mass production so they could also produce a large number of tanks and planes as well.
Had the Army Air Corp adopted the Pacific Naval aviation training for aviation marksmanship the Allies would have really devastated the German Air Force. The Pacific Naval Aviators were by far the best trained and best marksman of the world's aviators during the war. The Naval Aviators often practised marksmanship every other day when cruising with two carriers. One carrier provided CAP and sub patrols while the other practised high deflection shooting with towed targets and then alternated the next day. The Pacific aviators were the first to jury-rig deflection sights from Army bombers to aid them in high deflection shooting.
I don't disagree with any of that, but I can't fit all those discussions into a 20min video. I do cover some of those subjects to a small extent in other videos. Bottom line is that this is more of technical channel, so I don't really want to make a video on pilot training specifically. Thanks for your post, and again, I don't disagree with the importance of pilot training.
I doubt you are interested in my references. But ask yourself what are the pluses and minuses of the 20 mm air to air vs the pluses and minuses of the .50 cal.
18tangles, If you were surprised by my reference to bird hunting I must tell you that you are missing a lot of information on WW 2 aerial combat. This is a reference that many historical references include. You might want to do a good bit more reading if you really would like to better understand air combat during WW 2, but it seems that you feel like you are already the expert.
I think the first plane you showed may be a P-51A or an early variant. There's an early one on display at EAA here in Wisconsin before the bubble canopy was added. Either way, I love your channel.
Oh, that's a great guess Aaron, but it's an A36 Apache, very similar to the P51A. Notice the guns in the nose.
Thank you for the feedback and information :-). Always love to learn
these videos are really interesting! especially if you only have flight simulator experience :D
A-36 ground attacker, nose gun and razor back make it easy to distinguish
Good stuff as always!
That's fascinating. I can't believe many Navy fighters were ever flown to Angels 30, since they didn't escort many B-29s, and few Japanese planes could reach such a high altitude.
I doubt they did it very often, but they could!
I agree, plane version and pilot skill are very important factors on top of physics. Put Erich Hartman in a 109-K and he's probably outturning every P51 on the planet. Put a rookie in a 109-E and he's probably outturned by every P51 on the planet..
Ive seen P51s pulling 16 second turns for a second or two in other sims... but in WT its certainly NOT a turner, however, at a decent speed, it really can turn!
P-51 vs a P-40 in a turn and P-51, plus P-38 L Fowler combat flaps and wP-51 in a y
Everyone knows those History Channel dogfight tv series. I remember the story of a long, climbing diving contest involving a Corsair. A technical analysis and explanation behind this kind of story would be interesting to hear.
Great vid, got itself a sub
Like you said, power plays a big role here. And thus it depends entirely on which 109 variant and which engine setting the P-51 was running at. The P-51D before June 1944 was limited to only 67"Hg M.P. which equated to about 1630HP at takeoff. However after June 1944 it was cleared for 75"Hg and thus had about 1860HP at takeoff. A Mustang running this setting would out-turn any Gustav or Kurfurst 109, while being still being out-turned by the earlier 109F and E. Of course, this isn't taking into account fuel loads. The P-51Ds often faced 109s with lots of fuel loaded up, so that might have evened the playing field more.
Wow, I almost fell out of my chair when I saw someone commented on this video. Analytics show that this is by far my least popular video. Almost nobody has watched the whole thing. I guess calculating turn performance is much too technical even for this channel, which is why I am tending to focus more on engine stuff. That's what people seem to like, or at least my subscribers. Anyway, yes, at 75" and at certain altitudes, and of course depending on load, the P51 will have an advantage in sustained turn rates. However I have no plans to make a video about sustained turn rates of WW2 fighters since there seems to be almost zero interest in it.
Greg's >>> Too bad . I thought your video was interesting --very good . Oh well , guess I will have to watch funny cat videos .
Thanks James. My other videos seem to do pretty well. I am making quite a few more :)
I'm watching a load of videos recently to try to get my head around the relative capabilities of WW2 aircraft. After watching the "Dogfights" programme on the History channel, then trawling through a bunch of YT videos, and the arguments in the comments sections, it seems to be a case of "the more I learn, the more I realise I don't know."
I may be in a very small minority, but I for one would be very interested to watch a video giving details of the turn rates of various WW2 aircraft!
I'm sorry to hear that. Now I'll never find out how the airplane I wanted to fly in WW 2, the P-47, would have compared in turning performance to it's adversaries. I'm one of the nobodies that watched it all the way through.@@GregsAirplanesandAutomobiles
I did the calculation and turn radius as a function of speed, if without any structural limit, asymptotally approaches a value from above, that value being stall speed squared over g.
I'm not sure I understand. Math please.
Greg's Airplanes and Automobiles radius of maximum performance turn equals speed squared over (g times the square root of (v/vs)^4-1), vs being stall speed
The -1 compensates for the amount of lift spent in counteracting gravity instead of contributing to the turn. My calculation indicates that if without gravity, the airplane’s radius of maximum performance turn is constant disregarding of the speed.
This is what I use: www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/07_phak_ch5.pdf The math for this is on page 5-39. I would be curious to see if it comes out the same as your formula, I don't have time to do it right now because I am uploading a new video at this moment.
The aircraft in the early shot could be a P51; specifically, it could be an -A model, except for the dive brakes, which make it an A-36.
That's correct, the A36 and P51A are pretty similar. The main external difference are the dive brakes and nose mounted guns on the A36.
Sustained turn performance generally refers to turning at equilibrium: that is when the aircraft is not losing speed or altitude. If the P-51 were to have superior sustained turn performance that would be because it has more available engine power and wings with a higher CL/CD at the required CL (and thus angle of attack) for max g's. You cannot get sustained turn performance from only the numbers you used.
We didn't cover sustained turn performance in this video. I specifically said that in the video. I cover that in another video. In fact, I think I beat it to death in my P-47 pt. 5 video.
@@GregsAirplanesandAutomobiles Yes this only addresses the comment made right before at 12:24 which seems to imply that "more speed to lose" is related to sustained turn performance.
I understand. What I meant there is that the 51 would be able to maintain a higher average rate for some period of time because of the extra speed. That's not the same as sustained turn performance, but I see how it could have been viewed that way. I think you will like this video: th-cam.com/video/KahHLtYlveQ/w-d-xo.html
Love your video series, but I respectfully disagree with the idea that the mass of a plane doesn’t affect its turn performance. To turn an airplane (or anything else), you have to provide a lateral force to overcome the plane's linear momentum, which is its mass times its velocity. Obviously, it takes more force to change the momentum of a heavy object, than it does a light one. For an example, consider the centripetal force required to hold a plane in a circular turn. The equation for turn radius that you cite in the video is for a spiral, but the equations for a circle are better known, and the math is simpler, so I'm using it for my example. However, you can derive similar equations for a spiral, and get basically the same result.
As is well known, the centripetal force required to hold an object in a circular turn is...
F = m * V-squared / R
...where m = mass, V = tangential velocity, and R = turning radius.
In an airplane, the centripetal force provided primarily comes from the lift of the wings, times the sine of the bank angle. Again, as is well known, the equation for lift is...
L = F = ρ * Cd * A * V-squared
...where ρ = air density, Cd = Coefficient of Lift, A = wing area, and V = tangential velocity.
When the centripetal force required = centripetal force provided, the velocity-squared terms cancel out. Rearrange the equations, and the circular turn radius is...
R = m / [sine theta * ρ * Cd * A]
...where theta = the bank angle.
In other words, a sustained turn radius is proportional to the mass of the airplane, but inversely proportional to the bank angle, air density, and the lifting characteristics of the wings (and/or other lifting surfaces). At that point, speed no longer is a factor, so long as it's high enough to prevent stalling.
Why isn't airplane mass mentioned in the pilot's manual? My experience with operating manuals is that usually, they only address factors that the operator can control. Unless you count jettisoning fuel or stores, there isn't much a pilot can do about mass.
Take any airplane, but in this case, I'll use a 767. At 250,000 pounds, when at 250 knots in a 30 degree bank, the turn radius will be identical when at 350,000 pounds at 250 knots with 30 degrees of bank. Airplane manuals certainly do address mass, in the case of the 767-300 it could be flying at a weight anywhere between about 180,000 pounds, and 412,000 pounds. The manual has to address that as take off and landing distances will vary hugely, as will service ceiling. Now, your math isn't wrong, it's just that you are doing the wrong math problem. There will be further explanation of this concept in my next video, so rather than type several paragraphs here, I'll just get to work on that.
@@GregsAirplanesandAutomobiles - Hi, Greg - Prior to entering the turn, the heavier plane already will have been trimmed to give it an effectively larger coefficient of lift, leaving speed and bank angle as the two remaining variables determining its turn radius. It should be noted that the equation given for turn radius describes a spiral, suggesting the assumption of enough reserve wing loading to tighten the turn, so it's not at all surprising that, initially, at least, disparate airplanes, flying at the same speed and bank angle, will share a common radius (though probably not turn rate). My point is, that there's a limiting turn radius for which mass will be the dominant factor. Put another way, if - Lord help us - two 767s were to get into a dogfight, my money would be on the lighter of the two.
Chuckling...The British are here in the comments section blathering on about the spitfire this and that. Didn't see it in title, but, here they are! Again! Ridiculous! Ancient history pal, WHAT HAVE YOU DONE LATELY?
Overall, the British people are quite supportive of this channel. The youtube analytics show that. There are a few who seem to think the Spitfire was the most important plane of the war. It's my opinion that they are worshiping the wrong British plane, and there are other British planes that were of much greater significance to the war effort. Once I get the videos done covering basic engine and aerodynamic principles, then I'll start going more deeply into specific planes, and we will be discussing the Spitfire.
The interesting thing is that for instantaneous min radius, we don't *really* care about speed at all. It (very nearly) drops out of the equation in this regime.
Let k = 1/2 C_L A rho.
Any given wing has a fixed reference area and maximum lift coefficient. Rho is air density and is roughly a function of altitude.
Then maximum lift L = k v^2
R = v^2/a = mv^2/L = m/k = v_stall^2/g
The notable approximation is that this a = L/m isn't *quite* right for a level turn... it assume you bank straight sideways and god be darned if you lose some altitude. The more accurate expression is to correct it by the factor sqrt(1-1/g_factor^2). For a 7g level turn this is sqrt(1-1/7^2) ~ sqrt(1-1/50) ~ 1-1/100 = .99. If you are flying a bit slower at sea level and can only pull 4 g level it's about .97. Your turn radius will only be 2% more.
So we see that as long as you're broadly near the right speed, your turn radius is fairly insensitive to it. What matters operationally is reaching C_L_max, which in practice means pulling to just before the stall AoA. It also becomes obvious that flaps always tighten your turn instantaneously (since they increase lift/decrease stall speed) The reason why the plane needs so much farther to turn at altitude is air density. Turn radius is inversely proportional to air density, and 30,000 ft air is 3/10 as dense as at sea level, so the turn radius should be 10/3 times that at sea level. This is not very dependant on speed... even if you were able to go fast enough to pull 7g you would only decrease radius by 2% or so.
Which is why you can also say that roughly speaking, the relative turn performance of fighters is not a function of altitude in any condition where turn fighting is possible. If both fighters can pull more than 3 g or so then the one that turns tighter at sea level will still turn tighter at altitude, and by about the same amount. Only if you're in a condition where one fighter is near its ceiling and the other is not will there be a major change in this ratio.
According to Aerodynamics for Naval Aviators, maximum turn performance happens at the lowest speed at which the plane can pull it's maximum allowed G load, thus speed is a factor. Power is a factor in sustained turns at a constant altitude.
Like Erich Hartmann said, you cannot say this or that Airplane was better. It really depended what Pilot sat in them. And I heard that the ME 109 K4 was faster than the P-51. But I cannot really confirm if this is the case.
Oh there you are Hartmann, interesting detail. Thank you for sharing.
K.Bauer Yes, by some13 miles and better climb.
How about a video on Sustained turn rates as you mentioned?
I want to do that. Actually I sort of did with my Sopwith Camel vs. DR1 turn rate video, but it's not particularly scientific, more of a tutorial on a specific flight sim. I'll do a more complete video on this subject in the future.
Greg's Airplanes and Automobiles I really enjoy the WW2 planes videos many of my friends do too
Very interesting stuff. One thing that has me thinking would be more powerplant changes in aircraft. What made the Mustang the Mustang was the Spit's engine. It turned it from a decent aircraft into a high altitude beast that was also pretty fuel miserly and just very good overall in a fight. I would think there'd be no way for a Mustang to outturn a Spit due to Spit's near glider like wings. Both those wings, the Mustang's and the Spitfire's may be the most famous fighter wing designs of the war. One is as thin as it can be but is still deep because it holds a 20mm cannon. The other embraces laminar flow design that had its own neat effects. All of that gets a person to wondering what some aircraft would be like with the engine of another. Can you imagine a snub-nosed Mustang or Spit with a PW R-2800?
John R
A radial Mustang would largely fail, imo. The mustang was designed by a former racer, and as such, placed massive importance on low frontal area. Also, a lot of the drag reduction on the mustang was from the redesigned cooling system, which would have been useless with an air cooled engine.
Yeah, it'd be interesting to see and would also pick up significant drag as you stated. Radial fighters had that "jug" look which was one of the P-47's nicknames whereas a V-engine helps contribute to that sleek narrower look that we associate with the 'Stang, Spit, and Bf-109. Those 3 are among the most beautiful aircraft of the war.
Or a Mustang with a Griffon. It did happen, but postwar - and were only flown on the deck around pylons.
Good stuff, as usual.
Can you make a video about P51d disadvantages. Everybody talking only about P51d superiority, but there is got to be also some bad things. Could this aircraft compete with germans fighter in low/mid atitudes? Wasnt P51d also very vulnerable if it was hit in belly, because it didnt have strong protection?...
I feel like I have covered that in my P-47 series, and in my P-51 vs. Dora video. The P-51 was awesome, but not all conquering, a skilled pilot in a G-14 or a Dora will give it a tough time. I guess I could make a video on the specifics.
@@GregsAirplanesandAutomobiles Thank you for a quick response. Will check P-47 series. Have not watch this series yet. Anyway, these your videos are just masterpieces! :D
The hawker hurricane used to out turn the 109, it was it's one major advantage. Couldn't match it for top speed
In the BoB the Hurricane also out turned the Spit.
Of course the spit was continually developed as a fighter whereas the hurricane wasn't, but in 1940 the hurricane was probably the more effective of the two.
It wasn't as pretty tho so the ugly one got ignored a bit.
Many pilots tho expressed a preference for the hurricane, Bader included.
This is just fascinating to me. I wish I could have been good at math when I was younger.
Don't sweat the math, just use the chart, it's what the professionals do anyway, or these days, they use an online calculator.
Done anything with the P-38?