I am a 30,000 hour retired airline pilot with more than 57 years of flying experience and have been an active CFI in GA for the past 53 of those years. I was VERY impressed with your professionalism and how you saved your life through your superior airmanship and judgement. Well done!! You did all of the right things. My only suggestion is that in future situations like this, consider that aborting and running off the end of the runway is safer than colliding with the trees at nearly 100 mph. But since you survived, you made the correct PIC decision to continue. Lesser pilots would have hit the trees. Well done! I hope that someday you fly for the airlines as we need your skills and judgement on our flight decks.
Smart use of ground effect...saved my butt one day when I had a student get too slow on landing and used ground effect to make the runway! Nice analysis and thank you for sharing.
A GREAT video, so...that takeoff was experimental. You touched all the points, thanks bunches. Yeah...I found nose holding to the ground useful too, to control the instant of rotation because yes, runways can surprise.
I would find a different field to hangar the plane if the owner doesn't fix that asphalt. That runway is not suitable for canards. You need a better runway surface as well as more space especially with the obstacle at the end. Canards aren't designed to be shortfield planes and you are operating just within your safety envelope at this field. Good save though. When stuff starts to go sideways, you continue to fly the plane. Excellent debrief. Way to aviate, sir.
Personally, I would keep it in GE, due to reduction in drag, as long as possible due to getting to a higher airspeed, which would yield a better climb angle. Second, rather than trying to clear the trees with a huge margin, I would 'aim' for the tree tops, which would allow my airspeed to increase that much more, because I would rather have airspeed margin 'touching' the trees, than altitude margin with sketchy airspeed. This comes from years of hang gliding and motorcycling. If you have a vehicle that you are unsure of, it is better to 'pre-aim' at them slightly for two reasons, one to get their attention, and the second is if they DO pull out in front of you, you are already ready to go behind them. Varieze pilot here.
I have 35+ years riding motorcycles as well, so I know exactly of what you speak. :) I don't normally aim way over the treetops - I want as much airspeed as possible (it can get gusty once you're beyond the trees), so I generally aim to cross maybe 10-15 feet over them.
Firstly. Great outcome. I agree the pogo-ing is a real issue. Each upward ‘bounce’ increases the AoA on the canard and main wing. This increases the lift-induced drag, slowing your acceleration. Further, as you note, the increased AoA puts your canard in a flying state, but you are close to the back of the drag-curve, and this also slows your acceleration. The runway clearly needs some work, particularly for your canard aircraft. They like long, smooth runways. I don’t know much about your undercarriage detail, but you might investigate changing the spring-rate and rebound rate/damping. Reducing the nose wheel tyre pressure might also do something - although the runway does seem to need attention. I think this video, like your others, is great. Interesting, informative, and thought provoking.
I agree, and I do just that. The margin I normally build into my calculations is what got me over the trees in this case. I have more than once gone out to the airport, seen the winds and DA, and said "nope, not flying today." You can't fool physics. :)
this is a problem that normal non-canard aircraft can experience with aft center of gravity. Your analysis is very good and gives a good summary, how seemingly innocent conditions, which wouldn't cause any problem on their own, can add up quietly and cause a crash in some cases. suboptimal CoG --> warmer day --> slower acceleration --> longer distance for takeoff roll --> running into an unusual bumpy part --> early rotation --> more drag and even slower acceleration on the backside of the power curve (behind Vy). At this point, the pilot has no more than a fraction of a second to react. With obstacles being closer and higher than before, there is a very strong instint to pull up more --> create more drag --> slow down even more --> experience a power-on stall and spin --> crash vertically or inverted. It is good that your training kicked in.
All 100% correct except for the stall/spin - as a canard, it would have mushed into the trees, but not departed controlled flight/spun. You don't get a typical stall/spin with these planes, they just mush and come down fast. I'm sure that if you REALLY abused it, at aft (or especially beyond aft) C/G, at low speeds, you might be able to get the main wing to stall and subsequently spin - but I don't know that this has ever been attempted or tested. But yes, a good point (and also the point I was trying to make) about most incidents or crashes being a chain of events.
Man, pucker time for sure. Good save to you sir. Hopefully this dude will fix the runway, totally unsat. Sure glad you pulled this off, love that airplane, I suspect it does not buff out dents very well.
Yeah. It might cost a quarter million dollars or more to do it, so it will be quite a task to convince someone to take on such a financial risk. Even if you have the gumption to risk the family finances like that, the airport has to be viable. Not just niw, but for like the next 20 years or so. It's a tough one for all parties involved is what I'm getting at. General aviation isent growing like it did in the past due to fuel costs, weaker and weaker dollar, etc. This means lot of small airports end up with no future viability. I do pray this isn't one of those airports, cause I like it
I noticed the divider position on the windshield in the two takeoff were very different, as was your engine power (77% vs 83%), so I think your basic analysis is ok, however, the real issue is an improper takeoff plan. This is a short field on a summer day. You should hold the aircraft on the ground until to reach best angle speed and then climb to above treetop height by 100’ and then relaxed the climb to a more normal climb to pattern altitude. This is probably some like 83-85MPH. You are a lucky man with that large of a CG change only affecting you that much… it could have easily set you in the trees. You definitely need to calculate your numbers and practice that max takeoff climb a couple times before you take a passenger or more ballast. Cooler days ahead are great to test and adjust the process before the heat returns in earnest next summer. Document your results and do a followup on this video.
Density altitude has killed a lot of people and planes. Moving the CG forward and moving it reward will dramatically effect the performance of the aircraft. The deciding factor as you point out was the dip in the runway causing the air frame to get airborne at critical airspeed. You did every thing right and lived to tell us not what to do in this situation.
I'm delighted to hear that you have a new safer airport. I'm confident that you and the lovely airplane will enjoy many hours of safe aviation without nightmare of a line of trees coming up to meet you with nowhere to go. Safe flights
TBH, I Thk U R rolling the dice w. Your Life. Rwy Too Short, Obstacles too Close. Tarmac Condition may induce premature Pitch Oscillation which may affect AoA and Air Speed. Your plan should include finding a FBO with better Rwy Conditions. You might also Pony Up your Own Cash to Repair the Rwy, if you must stay there.
That normal takeoff was barely adequate, holy moly! Totally agree you need a longer runway and since you have a shitty home built. I’d find one without trees at the end. 😵💫
If you have to operate out of a field that's too short and too rough, then don't. Find another field, or different prop for climb performance and give up some top speed. I taught thousands of hours out of a 2k dirt strip and I can tell you that technique is a huge part of making it all work. And yes the density alt was a big deal.
That is the way to stay cool under pressure. Cool heads prevail, panicking doesn't solve anything. Excellent analysis! I've survived 3 partial engine failures in my flying career and fortunately I had a very cool flight instructor in the right seat when I was a low time private pilot on my first engine failure. It's extremely hard to deny instinct and push the nose over and point at the trees. This is where a lot of folks make the big mistake. The Velocity nose gear isn't quite as springy but it will pop you up in the air on a bumpy runway. When I trim for takeoff I push the stick forward to make sure I have flying speed when I rotate.
airport reminds me of catalina island… uphill with some potholes sprinkled in but even the most beaten up 20k aircraft hour flight school cessna did not bounce around like that ultimately you need to find an other runway… even with your great skillset you are setting yourself up for disaster if engine quits
You did an excellent job of dropping the nose to get the speed up, absolutely so difficult to fight your normal reaction to pull back to clear the trees. You saved yourself that day!
Thanks for sharing this. One positive, you did use all of the available runway. It could have been worse if you had started at the white line. Glad all is well, other than the change of trousers
I make a point of doing that ALWAYS, on every runway. Try explaining to your insurance company after the fact the reason why you didn't feel the need to use all of the available runway.
A bit spooky, but great data backup for confirmation/analysis purposes! Hope you can affect the needed runway improvements, and look forward to you showing off a new, faster rpm prop!
I have about 2000 hours in my cozy and would not operate off this runway. It’s too short and rough for your plane sorry to say. Go find a 4000 foot runway in good shape or get a different plane.
enjoying your videos more with the 'in cockpit/radio' transmissions and commentary. I am NOT a pilot, but that runway would not fill me with much confidence... hope there is no wear/damage being inflicted on your aircraft. keep the videos coming.
Hey Scott, thanks for sharing the video. Great job salvaging what could have been a bad situation. I don't know what your moment/arms are exactly, but in my Cozy 25# at the front seat station is ~11# at the ballast station to maintain the same CG which would keep 14# off the nose gear and get you to a lighter overall weight (better performance).
Good job Scott, that is a nasty runway with no safe engine failure after take off options. Great analysis, firstly I thought the bouncing was due to PIO but your info about the ballast makes sense. Hope you don't have to make another video like this but it was very interesting, especially with the unique configuration of the Cozy MKIV.
FASCINATING! Terrifying, but fascinating. Great analysis. I swear my heart is in my throat every time I see you take off on that runway. I’ll stop for gas at the other airport a few minutes away…
Awesome video. I had no idea that acceleration was greater (Less Drag) on the ground than in the air. I always thought the friction from the wheels would be greater and reduce once airborne. Makes sense though. Mushy, slow speed flight is not efficient.
The airplane will accelerate faster level in low ground effect than rolling on the runway. Rough runway and canard will hurt you here, but allowing the airplane to climb through low ground effect when too slow to safely fly is dangerous also. Wolfgang also talked about the experienced pilot trying to hit the tree rather than climb will over. Energy management begs us to use ground effect energy as long as we have runway available. Energy management begs us to pitch up to fly, not stall, just over the obstruction. As a crop duster, I have heard the farmer say, "You hit the tree." No, that was wing tip vorticies and downwash. Yes, I accelerated to max airspeed with full throttle in six inch ground effect over the crop and pitched to just over the trees. I alway had zoom reserve airspeed, airspeed sufficient to climb and/or maneuver with or with power, coming out of both crop field and airport. Energy management wise, they are the same thing. Get up to three feet or so and fast, but practice dynamic proactive elevator (canard) control movement over a long runway. I teach it with tractor airplanes with the elevator in back and they are easier to maintain level in low ground effect with. Your airplane is even more dependent on dynamic proactive fore/aft stick movement to bracket level in low ground effect. At your airport, especially with high DA, the low ground effect takeoff is the only safe takeoff with low powered airplanes.
I've been thoroughly enjoying all of your Cozy videos, and I'm beyond glad that this turned out to be just an incident. Once the TBO's up on this engine, would it be a good idea to sell it, and get a new one with more power, in order to increase the safety margin? I'll go watch your Gaia 2 video now, even though I definitely don't need another synth :)
Actually, I have a new Catto prop on order (currently being manufactured) that will give me a bit more static RPM, so I will make more power on takeoff from the engine that I already have. The GAIA is addictive! :)
Good save as a lot of people unfortunately would have panicked and end up in the Trees. Either stalling or decending into the tree. You didn't as you stayed calm assessed what was happening applied the correct inputs to get you outa trouble. NICE.
You need to upgrade your nose strut to include rebound damping asap (or drastically improve it if it's already damped) - otherwise you've just got a pogo stick, not really suspension. It's smart you're looking at the runway too, but suspension is a fundamental that'll protect you in future unforseen situations on other runways as well as your home base. You did a really good job underlining why the ability to gain airspeed at will *before* rotation is so valuable: decent suspension will give you that ability without a big cost or weight penalty given what you're flying . Great video, great analysis, great work. Thank you.
Brought back memories (not fond ones, either!). I wasn't flying a canard, but I had a situation that played out quite similarly: high DA, quartering headwind, aircraft near max weight for that DA, fairly short runway with an obstacle followed by trees beyond the runway end. The airport operator said that about the time I passed the midpoint of the runway, where I would normally have lifted off, he saw the windsock swing about 90 degrees (the windsock went out of my field of vision seconds before that) and make my quartering headwind a quartering tailwind. Thankfully, I was flying an aircraft that loves to be airborne so I was able to get up into ground effect and accelerate enough to climb over the first obstacle. As expected, I bled off some speed coming out of ground effect. Once I was over the first hurdle, I dropped the nose to pick up enough speed to get over the trees. That was something I never wanted to experience again, especially since I had my new fiance in the right seat!
I'm impressed. The reason so many low time pilots lose it during this type of event is simply lack of basic fundamentals of flight and specific a/c characteristics. You have both. knowing vx will certainly save you, but only when you have the time. This needs to be head out of the cockpit, instinctive awareness of the situation and experience. I have to commend you on your training regimen. Wow!
Thanks. Glad things worked out! You mentioned a speed that you would abort at below or fly at above it. This is normally associated with a point on the runway "if I don't have 65 knts at X" I abort. 😊
What you call pogo, in automotive I think the term is rebound. The start, compression is called jounce. So you have jounce and rebound. I worked as a machinist for Delta 22 years and flew out of ATL often. Not an A&P, but I pay attention to details. Atlanta's north inner runway used for taking off used to have the same problem almost center of the runway. You would go through a dip at a fairly high speed from the east end. If you watched you could see the wing tips going up and down a couple of cycles. And almost immediately after the plane settled down, we would rotate.
Just what I was asking me seeing the nose bumping, the balast. Canard is a pushing plane motor, so engaging trajectory. Solution is stand speed in pushing down the nose. But perhaps also to check the front wheel system. 👍🤔
Good insight you actually took the time to figure out what occurred, I always had an affinity for the "Cozy" but never knew this incident was a possibility.
Good information about CofG and discussing the moment arm (and yes of course, DA). Thank you for the self analysis. Sharing this well presented information makes the the aviation world safer. Also remain flexible with your abort speed. Sometimes a slow hit into trees on the ground is better than fast hit into trees from the air. A tough decision to make, yes. But one that depends on the situation, and can be life saving.
Two things: 1) Agree with the spring effect of the nose gear. I have used this phenomenon often in my LongEz to get the canard flying sooner (nose down and quickly nose up) and 2) You might want to lean the engine slightly to get max RPM. That’s the end of my Monday morning quarterbacking.
I fly a Long EZ and have the same springy nose strut issue. On my takeoffs I try to fly the nosewheel an inch or so off the runway during takeoff run to avoid the bouncy nose. It is somewhat of a compromise but the takeoff run is smoother.
Regarding your go/no-go decision you mentioned "stopping on the runway". Along that line you said something about being committed to go flying. Looking at the runway and the area beyond the runway just before the tree line I would submit that it might be preferable to go off the end of the runway at 20-30 miles an hour, dissipate more of that energy over the unimproved surface beyond the runway, before reaching the tree line rather than getting it airborne a few feet above the trees then stall/spinning directly into the ground or going straight into the trees at 65-75mph/knots. As far as survivability is concerned it is preferable to dissipate the energy involved in an aircraft incident/accident over a greater distance than coming to a sudden/abrupt stop. My point is that in your decision to stop/go you may want to consider more than "stopping on the runway". While your aircraft is a very nice, it is not a transport category aircraft with guaranteed performance; stopping on the available pavement, committed to go flying. It seems to me that you are thinking/talking in those T-Category Part 121 terms. No disrespect or cynical criticism intended, just something else to think about. Thank you for the well done and interesting video! -Respectfully
700 hours in a LongEZ here... I think you should unload the nose wheel as soon as possible in your takeoff run. As soon as I start my takeoff roll, I'm holding full aft stick to lift the nose as soon as the canard will fly. This should happen very soon in your takeoff roll. I just let the canard float just below the horizon so I can maintain forward visibility. Then I maintain that pitch attitude so that the aircraft lifts off as soon as the main wing wants to fly. Once the main wing lifts off, now both wings are flying. I then pitch forward if necessary to stay in ground effect until I reach optimal climb speed. It's similar to the way taildraggers lift the tail first to set the pitch angle, then let the aircraft liftoff when it's ready. You should never hold the nose on the ground during takeoff in a LongEZ or any variant of a LongEZ. This does two things in a canard. One, you never force the plane into the air. Two, it gets the nose wheel off the ground so debris is not thrown into the prop.
Actually, that's what I was doing in this video, which is why, when I hit that dip, it pushed the nose into the air (early). That said, normally I will rotate at 75-80 kts, and I will start applying back pressure at around 60-65 kts, and wait for it to come off. The canard will definitely not start flying below that (canard stall speed is 63 kts on this plane). And yes, as soon as I rotate and both wings are flying, I push forward to prevent over-rotation and stay in ground effect until Vx, like you mention.
Hi pretty new here, but was going to comment on runway improvement. I thought there must be county or federal funds to redo and extend the first few hundred feet where the excessive bouncing occurs. I'm curious how much the bouncing actually slows your TO roll. Also, that tree slot could be widened and lowered to make me more comfortable. Nice analysis!
Unfortunately, the airport is privately owned, so it does not qualify for county or federal funds. They did remove about 200 feet of trees from the north end of the runway, they are hoping to be able to remove more.
Right after the onset of the porpoising i seem to detect some resonance : the rebound on the damper is set too fast, so it jumps up and beyond the point of balance then drops down again, just as you approach a lull in the runway. So it takes all that downward nose momentum into the spring compression, and the cycle repeats itself. I would also consider offsetting your take-off run to the right by a few metres/yards looks like that might keep yr nosewheel inbetween most of the patches. Good job on pushing the nose down !
The rebound on the damper is not set too fast...because there IS no damper. It's just a spring. There's not enough room for a damper up there, and it would add weight to a very critical part of the plane.
I thought the nose porposing was going to be the culprit here. That is quite a story. Good learning point and time to assess when changes to the aircraft make flights, test flights again.
Thanks for your analysis. I'm a glider pilot thinking of getting my PPL. Never thought about the relationship of increased drag as you get off the ground because of lift generation. Very interesting!
Great job when recovering from the issue and many thanks to sharing your experience with us so that we are able to learn. I think of 2 things you might wanna try out next time: First if I saw it right the engine is not at full rpm when you release the breaks. So it may be worth waiting 1 or 2 more seconds spinning up the engine before releasing the brakes. Secondly you might want to try to pull the nose fully up when releasing the brakes and gently move the nose down to the normal settings while gaining speed. This way you help releasing the pressure on the front gear at the very start of the accelaration phase. It may help to avoid the early hard bumps and help to increase speed a bit more. At least at my plane C172 it works for me. If you are unsure please try it out at a longer runway!
Thanks that took some nerve, density altitude a hidden killer. Scary that those seemingly not so prominent factors added up to a near accident . I would also try cut the Canopies of the trees at the end a little shorter , that is not too expensive
That's what I face taking off from a grass strip. Speed building is slow and I have to rotate at 65mph and then I have to build speed in ground effect, then climb out at 70+mph. My Ercoupe won't even try to rotate below 65.
Ive seen this sort of thing many times - NOT with full size aircraft, but with model jets. Pre take off as we call it is when the model bounces up and tries to fly before it has enough airspeed (above the stall speed). It usually ends up in a stall and model destroyed.... That's why they don't tend to be flown off grass, due to bumps etc. We usually fly off tarmac runways etc, and not the concrete block ones, as the joins in the concrete slabs can cause this issue too for models. We call it kangarooing... Also the same issues on landing, if we hit a bump etc, it bounces the model back into the air and as we are landing, again (now at or below stall speed being on the ground) the model stalls and we end up picking bits up :( So i can totally relate to what you experienced with your take off. You've obviously identified the issues, but you do need a better runway! A model jet would have issues with that runway, never mind a full size one ... :)
We had a spot similar on our 5000’ runway at KHHG before they resurfaced it. I would have to also keep canard pressure down past this or we would get early lift off. It happened in our Q-2, Long Ez & Velocity. Maybe trying getting the canard up but pick up some speed before lifting the mains off might help but if practice some different techniques at a longer runway. Did you retract your nose before climbing above the trees? And if your close to us (Ft. Wayne area), I have digital scales to do a W&B. I’m not sure the DA should be that much of a factor. We also operate out of 800’ here in northern Indiana and not uncommon to see DA close to 3,000DA and went to Put-in-Bay Island this past August.
I did retract the nose as soon as I decided to continue climbing. I have scales here as well, I have a new prop coming (should give me more static RPM) and when I've got it on, I'm going to defuel and re-do the W&B from scratch, just so I have hard numbers to work with.
Maybe a possible fourth option... rearrange components of the airplane to achieve CG w/o having to add 50 pounds of ballast. That is a lot of ballast. Good decision making of keeping it in ground effect for that extra 5 seconds!
Canards such as this require ballast when flying single pilot in order to stay within C/G. If components were rearranged to not require this, then you could never carry a passenger in the front seat. I talk about this extensively in this video: th-cam.com/video/ycLQaiX4ylE/w-d-xo.html
Looks like my first take off in my Varieze. I was not used to the sensitive controls and over rotated into the scariest take off of my life. This is a mistake you only make once.
I was going to buy an ultra-light with a canard and not take lessons. John Denver changed my mind. Did lessons in a Piper and never had a scary moment like you did.
One thing to keep in mind, sometimes the best option is to kill the throttle and land on what's left. Yes you will overrun but that could be a better outcome compared to other options. Obviously not saying you should have done this here, but don't count out that option if at an airport with very little options if engine failure right at take off
Thank you for posting. Can you do more with the overlay of speeds/power/vsi? I love that telemetry data and gives a little context. Would love to see during all phases of flight, especially some landings. Keep up the great work.
I actually had to WRITE a piece of software to generate that, as I couldn't find anything available that did it. But I could use it for other videos as well.
I had the same thing happened to me in the mooney m20c. I had three regular sized men and I was taking it off in northern idaho runway that's real similar to what you have their trees on the end. I didn't think to stay in ground effect.😊 Never again
What a great idea of the airport to plant all those trees behind the runway. 😀 Glad that it turned out okay. Hopefully the runway will get fixed up one day. It will be so much more enjoyable then to use. And indeed would be better for their business also.
Being airborne does not create drag, the angle of attack does, caused by the plane's attitude. You could just stay in ground effect with the nose relatively low to minimize drag to gain enough airspeed.
Question about it not making drag without lift. Thinking in physics terms of the airplane being a system. If you have to use controls (elevator) to keep the plane from flying are you creating an equal or even higher amount of drag by opposing the lift causing the plane to want to leave the runway? I assume this would lead to less energy input to the aircraft as a system. Which of course we trade for airspeed or altitude. Not sure if this is correct, but makes sense in my head. When inadvertently entering flight below rotation speed (the runway bump in this case), it seems better to level off in ground effect for a few seconds to minimize drag instead of trying to keep it on the runway longer. Then getting airspeed up to Vx or Vy depending on the presence or absence of an obstacle ahead. Im no expert but hopefully someone with higher knowledge can clarify. Great video, thanks for making it
You don't need negative elevator input to stay on the ground - the angle of incidence of the aircraft on the ground is such that it already will not fly. You HAVE to add up elevator to pull the nose up in order to get the main wing to rotate and start generating lift. So just leaving the elevator neutral (assuming it is trimmed correctly for takeoff) will keep the nose (and the airplane) on the ground. Many conventional airplanes will fly themselves off the ground if you get the speed up high enough. Canards will not.
Good video. Seen so many video where the pilot couldn't break the instinct to keep pulling back and it ended badly. You made the right move, and quickly. Just wondering about that 25lb weight you moved from the passenger seat to the nose. Not sure how much distance it is from the seat to the forward mount point, but seems like for weight and balance it might be correct to cut the mass in half. Of course I don't have the weight/balance sheet like you do.
VERY educational. I like your airplane, I can't see you being happy with a 182. I would vote for trying to find some outside money to fix the runway and cut down some trees. There must be some programs and money available somewhere, they just have to be uncovered. This airport is a resource to the local area, no different than good highways and good bridges. Good luck. Besides, all these pesky details like a short runway in poor shape does help make you a better pilot. You have to think through what you are doing each and every time instead of flying on automatic.
Good explanation about keeping your nose down to build speed. It also looked like the bouncing from the bud runway pavement helped pop you up before you wanted.
Well-done and informative video. Because nearly all other types of planes will not porpoise that bad on the nose gear, I'm imagining the facility owner saying that to you, as he says "I'm not fixing it". If that ballast up front really made a positive change in flight handling, and you'd like it up there again, I'm wondering about changing that front spring to a stiffer one. It won't compress as much on the down-stroke, and won't throw the nose up as far on the upstroke. Maybe.
What about checking performance data as part of your preflight to insure adequate clearance over obstacles with maybe a little fudge factor added for safety? (i.e. not enough runway)
There is zero margin for error or any unforeseen circumstance on this runway (power loss, miscalculation of takeoff data...). This was a lucky one but even the "normal" takeoff looked scary...
As air traffic controller asked the instructor in the plàne I wàs tràining in, "Ahem, would you like to transfer to a longer runway?" We'd just skimmed the fence, as you did. You have an underpowered plane there, so you need a longer take off run.
If you look at the altitude over time graphs, the aircraft is in a better energy state in the incident takeoff , just compare 6.5 seconds in both takeoffs
Just wondering if you have thought about setting up flaperons on your ailerons for takeoff and landing? Loss of roll control maybe an issue. It should increase lift and drag as all flaps do and lower the angle of attack at landing for a less shallow approach profile.
It's not that easy. Both the canard and the main wing are lifting surfaces. If you increase lift on the main wing, you also have to have control surfaces that increase lift on the canard - while not exceeding the critical AOA on the canard (which is designed to exceed critical AOA before the main wing). And, you would need a mechanism that absolutely, positively prevents one system from actuating without the other actuating simultaneously - if that were to happen, it would be absolutely disastrous. Something like that would add a LOT of weight, comparably, to a small airplane like this. Loss of roll control is never an issue on a canard. That occurs on a conventional aircraft when the area of a wing which is stalled (begins at the wing root and travels outward) reaches the ailerons. On a canard, the main wing can NEVER stall because the canard stalls first, and reduces the AOA on the main wing before it gets anywhere near stalling, so the ailerons remain fully effective even at the lowest speeds - and even when the canard is held in a stall pitch buck.
As always nothing for free. More of a thought experiment. Was thinking about the rv12 flaperons. But on the canard aircraft you sort of get double value as aileron droop would require aft pitch trim. Which on a canard is down on the elevators. Hard to put that system in an already built aircraft.
I'm not a pilot but I saw that ground porpoising immediately and realized that was going bad places. If the runway is improved by the owner, is it safe to assume that an official has to come out to confirm and rate the new condition? And how long does it typically take to get that update info disseminated? I can see how delays there would be off putting towards investment.
This hard to say because, field conditions for GA airports are loose you can have everything from a perfectly smooth runway to a dirt strip and be with in regulation. Alot falls on the pilot to ensure his or her aircraft has the capabilities to perform safe take off and landings on any runway dirt or paved . Now let's say there's a giant pot hole or a hump in the middle of the strip it's the airport managers job to put a notam (notice to airman) out stating issues with that airports runway and then decide if the issue is unsafe and the runway needs to be closed or just an issue that pilots can over come with proper planning
Two things here: Why did you want to move the ballast forward if you were already in the W&B envelope? A forward CofG always takes longer runway. You would do better adding 10lbs in the nose rather than 25lbs under the co-pilots seat as that achieves the same balance but reduces your aircraft weight by 15lbs. Second point: If you keep your stick forward, the canard will not try to lift you off the runway prematurely and cause high induced drag and that porpoising. Keep the stick neutral, or forward, until you reach flying speed and then ease it off the runway. This gives you the shortest take off distance and no porpoising. Trying to pull a canard off the runway prematurely just does not work.
Yes, crappy runway, springy nose gear, I see a bad combination. Why back pressure at 60 kts, do you get nose wheel shimmy? Early take off like this are used for soft field but we then accelerate in the ground effect until climb speed. Good video!
No shimmy, but to unload the nosewheel at higher speed. It also starts to get the canard flying, and gives you the opportunity to start feeling how much back pressure you're going to need in order to rotate (which varies depending on load and C/G).
Your choice of starting location causes oscillation of the aircraft, in addition to Pilot induced oscillation, as you transition from blacktop onto concrete.
I think that was a bump which get you airborne prematurely. It just bumped high enough to get your wing to catch enough air to pick it up. Happens with this kind suspension.
the difference of the two departures is huge ! If that little density altitude has that big of a affect then my first thought is: under powered engine. How much HP is under the hood ?
You probably Stalled the Canard as it left Ground Effect, radically increasing the drag of the canard, hence the performance loss. I imagine it would just mush back down into ground effect an un-stalling itself in ground effect. Pushing forward on the stick until the main landing gear is rolling again with no intention to land, brings the canard back into un-stalled ground effect. Ground effect is not an on/off switch, the boost in lift is a function of altitude above the ground and wingspan. Your main wing will be in ground effect to a higher altitude above the runway than the canard. So, if the canard lifts off below "clear air" stall speed, in ground effect, your main wing which is closer to the ground and deeper in ground effect get a much better boost from ground effect. A stalled canard is not going to drop the nose down like a stall in "clear" air. A stalled canard at takeoff is only going to pitch the nose down back into ground effect, then begin flying again even below the stall speed.
The canard definitely did not stall, or come close to stall, first off the angle of attack even in clear air was nowhere near high enough, and definitely not high enough to stall IGE. If the AOA had increased sufficiently to stall the canard at that low altitude, the prop would have struck the ground. The immediate decrease in AOA you see is not a canard stall, rather it is me pushing the nose over in reaction to the unexpected rotation, to prevent further speed decay, and to prevent a prop strike. This is something that's pretty ingrained in canard pilots - it takes a fair amount of pitch back to unstick the nose, but as soon as it lifts, you have to unload that pitch input to prevent over-rotation. The stall/unstall cycle of the canard on this aircraft is typically about 1.5 - 2 Hz, so this was far too fast for it to be happening of its own accord anyway.
RE 65 as your go-no go, sure you may run off the runway into trees if faster than 65, but it looks like lots of trees extending initially in flying too with no real straight ahead landing options. Thoughts to low speed tree impact versus high speed tree impact and having certain items to abort regardless? The whole idea of sacrifice the plane to save occupants notion?
Great analysis. I really appreciate your sharing. One observation is that you did not describe the generally accepted rule-of-thumb for aborting takeoffs: If you haven't reached 70% of your takeoff speed by the time you've reached 50% of the length of the runway, then abort. You mentioned an inability to abort based on airspeed only. You should consider airspeed and position on the runway. For your airplane, it sounds like you should be at 50+ KIAS by the time you reach the mid-point on that runway. Were you tracking the runway mid-point during your takeoff? I did not hear you describe such. Great analysis on the effect of balast in the nose.
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I am a 30,000 hour retired airline pilot with more than 57 years of flying experience and have been an active CFI in GA for the past 53 of those years. I was VERY impressed with your professionalism and how you saved your life through your superior airmanship and judgement. Well done!! You did all of the right things. My only suggestion is that in future situations like this, consider that aborting and running off the end of the runway is safer than colliding with the trees at nearly 100 mph. But since you survived, you made the correct PIC decision to continue. Lesser pilots would have hit the trees. Well done! I hope that someday you fly for the airlines as we need your skills and judgement on our flight decks.
Smart use of ground effect...saved my butt one day when I had a student get too slow on landing and used ground effect to make the runway! Nice analysis and thank you for sharing.
A GREAT video, so...that takeoff was experimental. You touched all the points, thanks bunches. Yeah...I found nose holding to the ground useful too, to control the instant of rotation because yes, runways can surprise.
I would find a different field to hangar the plane if the owner doesn't fix that asphalt. That runway is not suitable for canards. You need a better runway surface as well as more space especially with the obstacle at the end. Canards aren't designed to be shortfield planes and you are operating just within your safety envelope at this field. Good save though. When stuff starts to go sideways, you continue to fly the plane. Excellent debrief. Way to aviate, sir.
2 things. 1) im so glad you are ok. 2) I actually understood everything you covered. Magic.
Personally, I would keep it in GE, due to reduction in drag, as long as possible due to getting to a higher airspeed, which would yield a better climb angle.
Second, rather than trying to clear the trees with a huge margin, I would 'aim' for the tree tops, which would allow my airspeed to increase
that much more, because I would rather have airspeed margin 'touching' the trees, than altitude margin with sketchy airspeed. This comes from years of hang gliding and motorcycling. If you have a vehicle that you are unsure of, it is better to 'pre-aim' at them slightly for two reasons, one to get their attention,
and the second is if they DO pull out in front of you, you are already ready to go behind them.
Varieze pilot here.
I have 35+ years riding motorcycles as well, so I know exactly of what you speak. :)
I don't normally aim way over the treetops - I want as much airspeed as possible (it can get gusty once you're beyond the trees), so I generally aim to cross maybe 10-15 feet over them.
@@CanardBoulevard Subbed btw 🙂
Firstly. Great outcome.
I agree the pogo-ing is a real issue. Each upward ‘bounce’ increases the AoA on the canard and main wing. This increases the lift-induced drag, slowing your acceleration. Further, as you note, the increased AoA puts your canard in a flying state, but you are close to the back of the drag-curve, and this also slows your acceleration.
The runway clearly needs some work, particularly for your canard aircraft. They like long, smooth runways. I don’t know much about your undercarriage detail, but you might investigate changing the spring-rate and rebound rate/damping. Reducing the nose wheel tyre pressure might also do something - although the runway does seem to need attention.
I think this video, like your others, is great. Interesting, informative, and thought provoking.
I agree, and I do just that. The margin I normally build into my calculations is what got me over the trees in this case.
I have more than once gone out to the airport, seen the winds and DA, and said "nope, not flying today." You can't fool physics. :)
this is a problem that normal non-canard aircraft can experience with aft center of gravity. Your analysis is very good and gives a good summary, how seemingly innocent conditions, which wouldn't cause any problem on their own, can add up quietly and cause a crash in some cases. suboptimal CoG --> warmer day --> slower acceleration --> longer distance for takeoff roll --> running into an unusual bumpy part --> early rotation --> more drag and even slower acceleration on the backside of the power curve (behind Vy). At this point, the pilot has no more than a fraction of a second to react. With obstacles being closer and higher than before, there is a very strong instint to pull up more --> create more drag --> slow down even more --> experience a power-on stall and spin --> crash vertically or inverted. It is good that your training kicked in.
All 100% correct except for the stall/spin - as a canard, it would have mushed into the trees, but not departed controlled flight/spun. You don't get a typical stall/spin with these planes, they just mush and come down fast. I'm sure that if you REALLY abused it, at aft (or especially beyond aft) C/G, at low speeds, you might be able to get the main wing to stall and subsequently spin - but I don't know that this has ever been attempted or tested.
But yes, a good point (and also the point I was trying to make) about most incidents or crashes being a chain of events.
Ty for sharing your analysts. I learned a lot
Man, pucker time for sure. Good save to you sir. Hopefully this dude will fix the runway, totally unsat. Sure glad you pulled this off, love that airplane, I suspect it does not buff out dents very well.
Yeah. It might cost a quarter million dollars or more to do it, so it will be quite a task to convince someone to take on such a financial risk.
Even if you have the gumption to risk the family finances like that, the airport has to be viable. Not just niw, but for like the next 20 years or so.
It's a tough one for all parties involved is what I'm getting at.
General aviation isent growing like it did in the past due to fuel costs, weaker and weaker dollar, etc. This means lot of small airports end up with no future viability.
I do pray this isn't one of those airports, cause I like it
I noticed the divider position on the windshield in the two takeoff were very different, as was your engine power (77% vs 83%), so I think your basic analysis is ok, however, the real issue is an improper takeoff plan. This is a short field on a summer day. You should hold the aircraft on the ground until to reach best angle speed and then climb to above treetop height by 100’ and then relaxed the climb to a more normal climb to pattern altitude. This is probably some like 83-85MPH. You are a lucky man with that large of a CG change only affecting you that much… it could have easily set you in the trees. You definitely need to calculate your numbers and practice that max takeoff climb a couple times before you take a passenger or more ballast. Cooler days ahead are great to test and adjust the process before the heat returns in earnest next summer. Document your results and do a followup on this video.
Density altitude has killed a lot of people and planes. Moving the CG forward and moving it reward will dramatically effect the performance of the aircraft. The deciding factor as you point out was the dip in the runway causing the air frame to get airborne at critical airspeed. You did every thing right and lived to tell us not what to do in this situation.
I'm delighted to hear that you have a new safer airport. I'm confident that you and the lovely airplane will enjoy many hours of safe aviation without nightmare of a line of trees coming up to meet you with nowhere to go. Safe flights
TBH, I Thk U R rolling the dice w. Your Life. Rwy Too Short, Obstacles too Close. Tarmac Condition may induce premature Pitch Oscillation which may affect AoA and Air Speed. Your plan should include finding a FBO with better Rwy Conditions. You might also Pony Up your Own Cash to Repair the Rwy, if you must stay there.
I agree. That runway is shit. Stop patching up bullshit and replace it
The owner needs to be reprimanded. Spend the cash!
I agree. Even his good flight was too close for me. Buy a vans for that airport
That normal takeoff was barely adequate, holy moly! Totally agree you need a longer runway and since you have a shitty home built. I’d find one without trees at the end. 😵💫
All valid points here. I think I would buy a chainsaw and cut down those trees at the end to give a path if needed at a lower altitude.
If you have to operate out of a field that's too short and too rough, then don't. Find another field, or different prop for climb performance and give up some top speed. I taught thousands of hours out of a 2k dirt strip and I can tell you that technique is a huge part of making it all work. And yes the density alt was a big deal.
That is the way to stay cool under pressure. Cool heads prevail, panicking doesn't solve anything. Excellent analysis! I've survived 3 partial engine failures in my flying career and fortunately I had a very cool flight instructor in the right seat when I was a low time private pilot on my first engine failure. It's extremely hard to deny instinct and push the nose over and point at the trees. This is where a lot of folks make the big mistake. The Velocity nose gear isn't quite as springy but it will pop you up in the air on a bumpy runway. When I trim for takeoff I push the stick forward to make sure I have flying speed when I rotate.
airport reminds me of catalina island… uphill with some potholes sprinkled in but even the most beaten up 20k aircraft hour flight school cessna did not bounce around like that
ultimately you need to find an other runway… even with your great skillset you are setting yourself up for disaster if engine quits
You did an excellent job of dropping the nose to get the speed up, absolutely so difficult to fight your normal reaction to pull back to clear the trees. You saved yourself that day!
Thanks for sharing this. One positive, you did use all of the available runway. It could have been worse if you had started at the white line. Glad all is well, other than the change of trousers
I make a point of doing that ALWAYS, on every runway. Try explaining to your insurance company after the fact the reason why you didn't feel the need to use all of the available runway.
@@CanardBoulevardUseless things in aviation:
Sky above
Runway behind
Fuel in the tanker
Yesterday's weather
Fly safe
A bit spooky, but great data backup for confirmation/analysis purposes! Hope you can affect the needed runway improvements, and look forward to you showing off a new, faster rpm prop!
Great video, great analysis, thank you for posting and sharing your experience with us.
I have about 2000 hours in my cozy and would not operate off this runway. It’s too short and rough for your plane sorry to say. Go find a 4000 foot runway in good shape or get a different plane.
Working on it.
-- Wow. Glad you are OK. Thanks for letting us know what happened. 🛩️
enjoying your videos more with the 'in cockpit/radio' transmissions and commentary. I am NOT a pilot, but that runway would not fill me with much confidence... hope there is no wear/damage being inflicted on your aircraft. keep the videos coming.
Hey Scott, thanks for sharing the video. Great job salvaging what could have been a bad situation. I don't know what your moment/arms are exactly, but in my Cozy 25# at the front seat station is ~11# at the ballast station to maintain the same CG which would keep 14# off the nose gear and get you to a lighter overall weight (better performance).
Good job Scott, that is a nasty runway with no safe engine failure after take off options. Great analysis, firstly I thought the bouncing was due to PIO but your info about the ballast makes sense. Hope you don't have to make another video like this but it was very interesting, especially with the unique configuration of the Cozy MKIV.
Wow glad you got a new airport. I figure 15 mph over stall for rotation maybe more when hot but I’m going to think about more now. 👍🇺🇸
This video helps me build knowledge, thank you for sharing
Exactly the reason I posted it. :)
Fascinating! I really enjoyed your pogo analysis. Clear & easily undetood explanations!
FASCINATING! Terrifying, but fascinating. Great analysis. I swear my heart is in my throat every time I see you take off on that runway. I’ll stop for gas at the other airport a few minutes away…
Awesome video. I had no idea that acceleration was greater (Less Drag) on the ground than in the air. I always thought the friction from the wheels would be greater and reduce once airborne. Makes sense though. Mushy, slow speed flight is not efficient.
The airplane will accelerate faster level in low ground effect than rolling on the runway. Rough runway and canard will hurt you here, but allowing the airplane to climb through low ground effect when too slow to safely fly is dangerous also. Wolfgang also talked about the experienced pilot trying to hit the tree rather than climb will over. Energy management begs us to use ground effect energy as long as we have runway available. Energy management begs us to pitch up to fly, not stall, just over the obstruction. As a crop duster, I have heard the farmer say, "You hit the tree." No, that was wing tip vorticies and downwash. Yes, I accelerated to max airspeed with full throttle in six inch ground effect over the crop and pitched to just over the trees. I alway had zoom reserve airspeed, airspeed sufficient to climb and/or maneuver with or with power, coming out of both crop field and airport. Energy management wise, they are the same thing.
Get up to three feet or so and fast, but practice dynamic proactive elevator (canard) control movement over a long runway. I teach it with tractor airplanes with the elevator in back and they are easier to maintain level in low ground effect with. Your airplane is even more dependent on dynamic proactive fore/aft stick movement to bracket level in low ground effect. At your airport, especially with high DA, the low ground effect takeoff is the only safe takeoff with low powered airplanes.
Great reaction and instincts to recover from a potential stall. Glad you’re here to tell the cautionary story.
Being a Canard, it won't stall per se, but it would have descended into the trees, so yeah...I'm glad I recovered properly as well!
I've been thoroughly enjoying all of your Cozy videos, and I'm beyond glad that this turned out to be just an incident. Once the TBO's up on this engine, would it be a good idea to sell it, and get a new one with more power, in order to increase the safety margin?
I'll go watch your Gaia 2 video now, even though I definitely don't need another synth :)
Actually, I have a new Catto prop on order (currently being manufactured) that will give me a bit more static RPM, so I will make more power on takeoff from the engine that I already have.
The GAIA is addictive! :)
Good save as a lot of people unfortunately would have panicked and end up in the Trees. Either stalling or decending into the tree. You didn't as you stayed calm assessed what was happening applied the correct inputs to get you outa trouble. NICE.
Well, I have been flying airplanes for 30 years. It's not my first time around. :)
It showed just ran with it solution appled excellent result.
You need to upgrade your nose strut to include rebound damping asap (or drastically improve it if it's already damped) - otherwise you've just got a pogo stick, not really suspension. It's smart you're looking at the runway too, but suspension is a fundamental that'll protect you in future unforseen situations on other runways as well as your home base. You did a really good job underlining why the ability to gain airspeed at will *before* rotation is so valuable: decent suspension will give you that ability without a big cost or weight penalty given what you're flying .
Great video, great analysis, great work. Thank you.
Brought back memories (not fond ones, either!). I wasn't flying a canard, but I had a situation that played out quite similarly: high DA, quartering headwind, aircraft near max weight for that DA, fairly short runway with an obstacle followed by trees beyond the runway end. The airport operator said that about the time I passed the midpoint of the runway, where I would normally have lifted off, he saw the windsock swing about 90 degrees (the windsock went out of my field of vision seconds before that) and make my quartering headwind a quartering tailwind. Thankfully, I was flying an aircraft that loves to be airborne so I was able to get up into ground effect and accelerate enough to climb over the first obstacle. As expected, I bled off some speed coming out of ground effect. Once I was over the first hurdle, I dropped the nose to pick up enough speed to get over the trees. That was something I never wanted to experience again, especially since I had my new fiance in the right seat!
That's scary! Glad you did the right thing, I've heard from several pilots now who have had similar experiences.
So glad you survived man, the videos taken were definitely crucial to determining the cause, hopefully this saves lives
Thank you for the detail. I'm not a pilot, as much as I wish I was. I didn't understand why you did not just abort till you explained it.
I'm impressed. The reason so many low time pilots lose it during this type of event is simply lack of basic fundamentals of flight and specific a/c characteristics. You have both. knowing vx will certainly save you, but only when you have the time. This needs to be head out of the cockpit, instinctive awareness of the situation and experience. I have to commend you on your training regimen. Wow!
Thank you for sharing your experience. Until the runway is fixed, it will be very wise to do SOFT field takeoffs and landings.
Thanks. Glad things worked out! You mentioned a speed that you would abort at below or fly at above it. This is normally associated with a point on the runway "if I don't have 65 knts at X" I abort. 😊
You might want to look into changing props I've watched a lot of videos on the subject and I'm amazed what a change that can make.
Already underway, I've had a new prop on order for months now, it should be coming in a few weeks.
Great analysis
What you call pogo, in automotive I think the term is rebound. The start, compression is called jounce. So you have jounce and rebound.
I worked as a machinist for Delta 22 years and flew out of ATL often. Not an A&P, but I pay attention to details. Atlanta's north inner runway used for taking off used to have the same problem almost center of the runway. You would go through a dip at a fairly high speed from the east end. If you watched you could see the wing tips going up and down a couple of cycles. And almost immediately after the plane settled down, we would rotate.
Just what I was asking me seeing the nose bumping, the balast. Canard is a pushing plane motor, so engaging trajectory. Solution is stand speed in pushing down the nose. But perhaps also to check the front wheel system. 👍🤔
Good insight you actually took the time to figure out what occurred, I always had an affinity for the "Cozy" but never knew this incident was a possibility.
Good information about CofG and discussing the moment arm (and yes of course, DA). Thank you for the self analysis. Sharing this well presented information makes the the aviation world safer. Also remain flexible with your abort speed. Sometimes a slow hit into trees on the ground is better than fast hit into trees from the air. A tough decision to make, yes. But one that depends on the situation, and can be life saving.
Two things: 1) Agree with the spring effect of the nose gear. I have used this phenomenon often in my LongEz to get the canard flying sooner (nose down and quickly nose up) and 2) You might want to lean the engine slightly to get max RPM. That’s the end of my Monday morning quarterbacking.
I fly a Long EZ and have the same springy nose strut issue. On my takeoffs I try to fly the nosewheel an inch or so off the runway during takeoff run to avoid the bouncy nose. It is somewhat of a compromise but the takeoff run is smoother.
Regarding your go/no-go decision you mentioned "stopping on the runway". Along that line you said something about being committed to go flying. Looking at the runway and the area beyond the runway just before the tree line I would submit that it might be preferable to go off the end of the runway at 20-30 miles an hour, dissipate more of that energy over the unimproved surface beyond the runway, before reaching the tree line rather than getting it airborne a few feet above the trees then stall/spinning directly into the ground or going straight into the trees at 65-75mph/knots. As far as survivability is concerned it is preferable to dissipate the energy involved in an aircraft incident/accident over a greater distance than coming to a sudden/abrupt stop. My point is that in your decision to stop/go you may want to consider more than "stopping on the runway". While your aircraft is a very nice, it is not a transport category aircraft with guaranteed performance; stopping on the available pavement, committed to go flying. It seems to me that you are thinking/talking in those T-Category Part 121 terms. No disrespect or cynical criticism intended, just something else to think about. Thank you for the well done and interesting video!
-Respectfully
700 hours in a LongEZ here...
I think you should unload the nose wheel as soon as possible in your takeoff run.
As soon as I start my takeoff roll, I'm holding full aft stick to lift the nose as soon as the canard will fly. This should happen very soon in your takeoff roll. I just let the canard float just below the horizon so I can maintain forward visibility. Then I maintain that pitch attitude so that the aircraft lifts off as soon as the main wing wants to fly.
Once the main wing lifts off, now both wings are flying. I then pitch forward if necessary to stay in ground effect until I reach optimal climb speed.
It's similar to the way taildraggers lift the tail first to set the pitch angle, then let the aircraft liftoff when it's ready. You should never hold the nose on the ground during takeoff in a LongEZ or any variant of a LongEZ.
This does two things in a canard. One, you never force the plane into the air. Two, it gets the nose wheel off the ground so debris is not thrown into the prop.
Actually, that's what I was doing in this video, which is why, when I hit that dip, it pushed the nose into the air (early). That said, normally I will rotate at 75-80 kts, and I will start applying back pressure at around 60-65 kts, and wait for it to come off. The canard will definitely not start flying below that (canard stall speed is 63 kts on this plane). And yes, as soon as I rotate and both wings are flying, I push forward to prevent over-rotation and stay in ground effect until Vx, like you mention.
Hi pretty new here, but was going to comment on runway improvement. I thought there must be county or federal funds to redo and extend the first few hundred feet where the excessive bouncing occurs. I'm curious how much the bouncing actually slows your TO roll.
Also, that tree slot could be widened and lowered to make me more comfortable.
Nice analysis!
Unfortunately, the airport is privately owned, so it does not qualify for county or federal funds. They did remove about 200 feet of trees from the north end of the runway, they are hoping to be able to remove more.
Right after the onset of the porpoising i seem to detect some resonance : the rebound on the damper is set too fast, so it jumps up and beyond the point of balance then drops down again, just as you approach a lull in the runway. So it takes all that downward nose momentum into the spring compression, and the cycle repeats itself. I would also consider offsetting your take-off run to the right by a few metres/yards looks like that might keep yr nosewheel inbetween most of the patches. Good job on pushing the nose down !
The rebound on the damper is not set too fast...because there IS no damper. It's just a spring. There's not enough room for a damper up there, and it would add weight to a very critical part of the plane.
I thought the nose porposing was going to be the culprit here. That is quite a story. Good learning point and time to assess when changes to the aircraft make flights, test flights again.
Thanks for your analysis. I'm a glider pilot thinking of getting my PPL. Never thought about the relationship of increased drag as you get off the ground because of lift generation. Very interesting!
Great job when recovering from the issue and many thanks to sharing your experience with us so that we are able to learn.
I think of 2 things you might wanna try out next time: First if I saw it right the engine is not at full rpm when you release the breaks. So it may be worth waiting 1 or 2 more seconds spinning up the engine before releasing the brakes.
Secondly you might want to try to pull the nose fully up when releasing the brakes and gently move the nose down to the normal settings while gaining speed. This way you help releasing the pressure on the front gear at the very start of the accelaration phase. It may help to avoid the early hard bumps and help to increase speed a bit more. At least at my plane C172 it works for me. If you are unsure please try it out at a longer runway!
Good advice for more traditional aircraft but his is a pusher prop
Thanks that took some nerve, density altitude a hidden killer.
Scary that those seemingly not so prominent factors added up to a near accident .
I would also try cut the Canopies of the trees at the end a little shorter , that is not too expensive
That's what I face taking off from a grass strip. Speed building is slow and I have to rotate at 65mph and then I have to build speed in ground effect, then climb out at 70+mph. My Ercoupe won't even try to rotate below 65.
Ive seen this sort of thing many times - NOT with full size aircraft, but with model jets. Pre take off as we call it is when the model bounces up and tries to fly before it has enough airspeed (above the stall speed). It usually ends up in a stall and model destroyed.... That's why they don't tend to be flown off grass, due to bumps etc. We usually fly off tarmac runways etc, and not the concrete block ones, as the joins in the concrete slabs can cause this issue too for models. We call it kangarooing... Also the same issues on landing, if we hit a bump etc, it bounces the model back into the air and as we are landing, again (now at or below stall speed being on the ground) the model stalls and we end up picking bits up :( So i can totally relate to what you experienced with your take off. You've obviously identified the issues, but you do need a better runway! A model jet would have issues with that runway, never mind a full size one ... :)
I always thought that springy arm on the nose gear was a bit of a design mistake for similar reasons.
Omg. Scary runway conditions and tree line. Thank God you are safe and moving to a new location. What would have happened if two souls on board?
Could one add a tad of downward trim to help keep nose planted until the pilot is ready for liftoff?
Great video & plane.
Love the cannard
We had a spot similar on our 5000’ runway at KHHG before they resurfaced it. I would have to also keep canard pressure down past this or we would get early lift off. It happened in our Q-2, Long Ez & Velocity.
Maybe trying getting the canard up but pick up some speed before lifting the mains off might help but if practice some different techniques at a longer runway. Did you retract your nose before climbing above the trees? And if your close to us (Ft. Wayne area), I have digital scales to do a W&B.
I’m not sure the DA should be that much of a factor. We also operate out of 800’ here in northern Indiana and not uncommon to see DA close to 3,000DA and went to Put-in-Bay Island this past August.
I did retract the nose as soon as I decided to continue climbing. I have scales here as well, I have a new prop coming (should give me more static RPM) and when I've got it on, I'm going to defuel and re-do the W&B from scratch, just so I have hard numbers to work with.
Maybe a possible fourth option... rearrange components of the airplane to achieve CG w/o having to add 50 pounds of ballast. That is a lot of ballast. Good decision making of keeping it in ground effect for that extra 5 seconds!
Canards such as this require ballast when flying single pilot in order to stay within C/G. If components were rearranged to not require this, then you could never carry a passenger in the front seat. I talk about this extensively in this video: th-cam.com/video/ycLQaiX4ylE/w-d-xo.html
@@CanardBoulevard Interesting. I'll check it out.
Looks like my first take off in my Varieze. I was not used to the sensitive controls and over rotated into the scariest take off of my life. This is a mistake you only make once.
Thanks for this video. I appreciate you sharing your thought processes and your scary experience for us all to learn from.
I was going to buy an ultra-light with a canard and not take lessons. John Denver changed my mind. Did lessons in a Piper and never had a scary moment like you did.
That is why I like planes with more power than they need..turbo.. . That runway combo with that plane gives me the ebeegeebies.
One thing to keep in mind, sometimes the best option is to kill the throttle and land on what's left. Yes you will overrun but that could be a better outcome compared to other options. Obviously not saying you should have done this here, but don't count out that option if at an airport with very little options if engine failure right at take off
Thank you for posting. Can you do more with the overlay of speeds/power/vsi? I love that telemetry data and gives a little context. Would love to see during all phases of flight, especially some landings. Keep up the great work.
I actually had to WRITE a piece of software to generate that, as I couldn't find anything available that did it. But I could use it for other videos as well.
I had the same thing happened to me in the mooney m20c. I had three regular sized men and I was taking it off in northern idaho runway that's real similar to what you have their trees on the end. I didn't think to stay in ground effect.😊 Never again
What a great idea of the airport to plant all those trees behind the runway. 😀
Glad that it turned out okay. Hopefully the runway will get fixed up one day. It will be so much more enjoyable then to use. And indeed would be better for their business also.
Same symptoms that I had once with a pilot induced density altitude effect on the engine or I left carb heat on
attempting to climb after a T & G.
Being airborne does not create drag, the angle of attack does, caused by the plane's attitude. You could just stay in ground effect with the nose relatively low to minimize drag to gain enough airspeed.
Question about it not making drag without lift. Thinking in physics terms of the airplane being a system. If you have to use controls (elevator) to keep the plane from flying are you creating an equal or even higher amount of drag by opposing the lift causing the plane to want to leave the runway? I assume this would lead to less energy input to the aircraft as a system. Which of course we trade for airspeed or altitude.
Not sure if this is correct, but makes sense in my head. When inadvertently entering flight below rotation speed (the runway bump in this case), it seems better to level off in ground effect for a few seconds to minimize drag instead of trying to keep it on the runway longer. Then getting airspeed up to Vx or Vy depending on the presence or absence of an obstacle ahead. Im no expert but hopefully someone with higher knowledge can clarify.
Great video, thanks for making it
You don't need negative elevator input to stay on the ground - the angle of incidence of the aircraft on the ground is such that it already will not fly. You HAVE to add up elevator to pull the nose up in order to get the main wing to rotate and start generating lift. So just leaving the elevator neutral (assuming it is trimmed correctly for takeoff) will keep the nose (and the airplane) on the ground. Many conventional airplanes will fly themselves off the ground if you get the speed up high enough. Canards will not.
Good video. Seen so many video where the pilot couldn't break the instinct to keep pulling back and it ended badly. You made the right move, and quickly. Just wondering about that 25lb weight you moved from the passenger seat to the nose. Not sure how much distance it is from the seat to the forward mount point, but seems like for weight and balance it might be correct to cut the mass in half. Of course I don't have the weight/balance sheet like you do.
VERY educational. I like your airplane, I can't see you being happy with a 182. I would vote for trying to find some outside money to fix the runway and cut down some trees. There must be some programs and money available somewhere, they just have to be uncovered. This airport is a resource to the local area, no different than good highways and good bridges. Good luck. Besides, all these pesky details like a short runway in poor shape does help make you a better pilot. You have to think through what you are doing each and every time instead of flying on automatic.
Very true. Every takeoff and landing. I have gone to that airport, seen the crosswind and density altitude, and said, "nope, not flying today."
Good explanation about keeping your nose down to build speed. It also looked like the bouncing from the bud runway pavement helped pop you up before you wanted.
Exactly what I described.
Well-done and informative video. Because nearly all other types of planes will not porpoise that bad on the nose gear, I'm imagining the facility owner saying that to you, as he says "I'm not fixing it".
If that ballast up front really made a positive change in flight handling, and you'd like it up there again, I'm wondering about changing that front spring to a stiffer one. It won't compress as much on the down-stroke, and won't throw the nose up as far on the upstroke. Maybe.
What about checking performance data as part of your preflight to insure adequate clearance over obstacles with maybe a little fudge factor added for safety? (i.e. not enough runway)
There is zero margin for error or any unforeseen circumstance on this runway (power loss, miscalculation of takeoff data...). This was a lucky one but even the "normal" takeoff looked scary...
As air traffic controller asked the instructor in the plàne I wàs tràining in, "Ahem, would you like to transfer to a longer runway?" We'd just skimmed the fence, as you did. You have an underpowered plane there, so you need a longer take off run.
If you look at the altitude over time graphs, the aircraft is in a better energy state in the incident takeoff , just compare 6.5 seconds in both takeoffs
You need to find a way to add a damper to the front wheel. That will stop the bounce, and add a little nose ballast.
As I noted, adding ballast actually made it worse, and is part of the issue that caused this.
Just wondering if you have thought about setting up flaperons on your ailerons for takeoff and landing? Loss of roll control maybe an issue. It should increase lift and drag as all flaps do and lower the angle of attack at landing for a less shallow approach profile.
It's not that easy. Both the canard and the main wing are lifting surfaces. If you increase lift on the main wing, you also have to have control surfaces that increase lift on the canard - while not exceeding the critical AOA on the canard (which is designed to exceed critical AOA before the main wing). And, you would need a mechanism that absolutely, positively prevents one system from actuating without the other actuating simultaneously - if that were to happen, it would be absolutely disastrous. Something like that would add a LOT of weight, comparably, to a small airplane like this.
Loss of roll control is never an issue on a canard. That occurs on a conventional aircraft when the area of a wing which is stalled (begins at the wing root and travels outward) reaches the ailerons. On a canard, the main wing can NEVER stall because the canard stalls first, and reduces the AOA on the main wing before it gets anywhere near stalling, so the ailerons remain fully effective even at the lowest speeds - and even when the canard is held in a stall pitch buck.
As always nothing for free. More of a thought experiment. Was thinking about the rv12 flaperons. But on the canard aircraft you sort of get double value as aileron droop would require aft pitch trim. Which on a canard is down on the elevators. Hard to put that system in an already built aircraft.
I'm not a pilot but I saw that ground porpoising immediately and realized that was going bad places. If the runway is improved by the owner, is it safe to assume that an official has to come out to confirm and rate the new condition? And how long does it typically take to get that update info disseminated? I can see how delays there would be off putting towards investment.
This hard to say because, field conditions for GA airports are loose you can have everything from a perfectly smooth runway to a dirt strip and be with in regulation. Alot falls on the pilot to ensure his or her aircraft has the capabilities to perform safe take off and landings on any runway dirt or paved . Now let's say there's a giant pot hole or a hump in the middle of the strip it's the airport managers job to put a notam (notice to airman) out stating issues with that airports runway and then decide if the issue is unsafe and the runway needs to be closed or just an issue that pilots can over come with proper planning
@@DocbritoFMF Thank you.
Scary take off for sure. Would have been nice to have a bit more power as insurance.
Two things here:
Why did you want to move the ballast forward if you were already in the W&B envelope? A forward CofG always takes longer runway. You would do better adding 10lbs in the nose rather than 25lbs under the co-pilots seat as that achieves the same balance but reduces your aircraft weight by 15lbs.
Second point: If you keep your stick forward, the canard will not try to lift you off the runway prematurely and cause high induced drag and that porpoising. Keep the stick neutral, or forward, until you reach flying speed and then ease it off the runway. This gives you the shortest take off distance and no porpoising. Trying to pull a canard off the runway prematurely just does not work.
Yes, crappy runway, springy nose gear, I see a bad combination. Why back pressure at 60 kts, do you get nose wheel shimmy? Early take off like this are used for soft field but we then accelerate in the ground effect until climb speed. Good video!
No shimmy, but to unload the nosewheel at higher speed. It also starts to get the canard flying, and gives you the opportunity to start feeling how much back pressure you're going to need in order to rotate (which varies depending on load and C/G).
Hard nope on that paved cow path!😂
You might try having the runway repaired. It would give you a smooth transition while gathering your airspeed for takeoff.
Your choice of starting location causes oscillation of the aircraft, in addition to Pilot induced oscillation, as you transition from blacktop onto concrete.
I wouldn’t normally fly out of there but when I do I would make sure I did a short field take off.
Thank you for sharing.
I think that was a bump which get you airborne prematurely. It just bumped high enough to get your wing to catch enough air to pick it up. Happens with this kind suspension.
the difference of the two departures is huge !
If that little density altitude has that big of a affect then my first thought is: under powered engine.
How much HP is under the hood ?
You probably Stalled the Canard as it left Ground Effect, radically increasing the drag of the canard, hence the performance loss. I imagine it would just mush back down into ground effect an un-stalling itself in ground effect. Pushing forward on the stick until the main landing gear is rolling again with no intention to land, brings the canard back into un-stalled ground effect.
Ground effect is not an on/off switch, the boost in lift is a function of altitude above the ground and wingspan. Your main wing will be in ground effect to a higher altitude above the runway than the canard. So, if the canard lifts off below "clear air" stall speed, in ground effect, your main wing which is closer to the ground and deeper in ground effect get a much better boost from ground effect. A stalled canard is not going to drop the nose down like a stall in "clear" air. A stalled canard at takeoff is only going to pitch the nose down back into ground effect, then begin flying again even below the stall speed.
The canard definitely did not stall, or come close to stall, first off the angle of attack even in clear air was nowhere near high enough, and definitely not high enough to stall IGE. If the AOA had increased sufficiently to stall the canard at that low altitude, the prop would have struck the ground. The immediate decrease in AOA you see is not a canard stall, rather it is me pushing the nose over in reaction to the unexpected rotation, to prevent further speed decay, and to prevent a prop strike. This is something that's pretty ingrained in canard pilots - it takes a fair amount of pitch back to unstick the nose, but as soon as it lifts, you have to unload that pitch input to prevent over-rotation.
The stall/unstall cycle of the canard on this aircraft is typically about 1.5 - 2 Hz, so this was far too fast for it to be happening of its own accord anyway.
RE 65 as your go-no go, sure you may run off the runway into trees if faster than 65, but it looks like lots of trees extending initially in flying too with no real straight ahead landing options. Thoughts to low speed tree impact versus high speed tree impact and having certain items to abort regardless? The whole idea of sacrifice the plane to save occupants notion?
Watched 1st and 2nd takeoff several times… Both look perfectly normal to me 🙈
Great analysis. I really appreciate your sharing. One observation is that you did not describe the generally accepted rule-of-thumb for aborting takeoffs: If you haven't reached 70% of your takeoff speed by the time you've reached 50% of the length of the runway, then abort. You mentioned an inability to abort based on airspeed only. You should consider airspeed and position on the runway. For your airplane, it sounds like you should be at 50+ KIAS by the time you reach the mid-point on that runway. Were you tracking the runway mid-point during your takeoff? I did not hear you describe such. Great analysis on the effect of balast in the nose.
Yes, mid-point on that runway is where you see the fence end and the trees begin on the left side, and that is normally my rotation point.