@@blancolirio What would cause the overspeed? A sudden increase in air-fuel mixture into the cylinders? Is that possible? Is the engine supercharged or turbo supercharged? Or a flattening of propeller pitch? I mean, we don’t know; but what are the possible causes?
I don't think we can read too much into that. The overspeed might have been preceded by a prop control failure, the nature of which we don't know, therefore we don't know the possible consequences of such a failure. Those consequences might include blade separation independent of prop speed.
Is that conclusion (which came first) being drawn from eyewitness testimony? Eyewitness testimony is very unreliable and an overspeed from hub failure seems WAY more plausible than, say, he hit the nitrous boost or something.
The mechanical failure made an emergency landing urgently necessary, but it was the lack of a good place for that landing which made this a fatal crash. The solo post-maintenance test flight saved the planned passenger from serious injury or death, which demonstrates that test piloting is both dangerous and necessary. RIP.
I met this guy last year and saw this plane at the Cleveland Interational Air Show, he was really nice and answered a bunch of questions about the plane, homebuilding, his different kits, and business. Really sad. RIP sir.
Thanks Juan, another excellent report. My sincere condolences to the pilot's friends and family. I would observe, as an engine guy - that any time I see or hear an engine overspeed suddenly - especially in a condition where one would normally expect the load to be increasing, my experience causes me to suspect that the load suddenly came off the engine. It is difficult to overspeed a fully loaded engine. Perhaps, a pitch control failure, unloading the engine? I will be waiting to hear what they end up determining the root cause of the overspeed was.
The sequence was most likely, that the hub failed, then the blades separated, then the revs went through the red line. A ground observer would see the blades separate first, then maybe 3 seconds later would hear the bang and then the revs rise.
Since over-speeding is a major concern, I'd think there would be a rev limiter set to a value within the normal operating parameters. My guess is something failed prior to the rev increase that caused the revs to rise even with rev limiter intervention.
@BlingtingSam I have been almost killed 3 times by million dollar aircrafts. One wich was a total loss due to engine failure 300 hours on the airframe . Their most concern, not " crappy " aircraft, and you, sir, are disrespect and uneducated. Have a nice day.
Well there is no disputing something crapped out. The guy designed it, guy built it, guy test flew it, and understandably found a lethal limitation. Better he then one of his clients. Who if it were they who died instead of him, you can bet your ass the lawyers would be making his life hell. RIP to him or whatever comes next. He knew the risk, he died trying to push the design envelope to see where it fails. same as every other Experimental plane. He obviously loved what he was doing. Like helicopter pilots. More die flying in a helicopter before reaching 3000 hours in type, than get beyond that. Cause they love to fly helicopters. I know of a ' Nam Cobra Pilot, who in civillian life flew 315 Lamas . Had 1000's of hours. After his second "bent bird" incident over his decades, he hung it up. He knew the next time would be his last time, and had a family member needing continuing care. Also flew with a very famous jillions of hours motion picture helicopter stunt pilot. Nice guy, very professional, and detailed emphatically the purpose of the mission, and what the cameraperson limitations are, before flight. Later he died doing what he loved. Flight is always risky business.
I had a 310P and had to rebuild the props. Learned way more than I wanted to know. The hubs keep the props from centrifugal forces exceeding 20 tons each if I remember right. When you have one fail it is catastrophic. It can rip the engine right out of the frame. Condolences to him, his family and friends.
Centrifugal force is a misnomer. It does not exist as a force in the realities of physics. Centripetal force is a real force that keeps an object moving in a circle, while centrifugal force is an apparent force that pushes an object away from the center of a circle: Centripetal force A real force that acts towards the center of a circle, or the axis of rotation, to keep an object moving in a circle.
@@danblumel The difference is mostly philosophical here, we are talking about the stresses upon the propeller hub. It also depends on your reference frame, which for the propeller hub is spinning at a few 1000 RPM … How about you tackle a force being expressed in units of inertial mass (20 tons) instead of units of force (about 196,000,000 Newton)?
@@danblumelThe centrifugal force is the problem because it pulls from center. Ie the hub being center and the ends of the props being the outer circumference. When a prop fails the hub is pulled from center from said force. The reason it is centrifugal is because of the imparted rotation from the connecting rods to the crank to the hub. Making it a force that wants to push away from center when a prop fails.
Not sure if it applies to this engine and gear box but I remember talking to someone about these LS automotive conversions. One of the major drawbacks was you couldn’t pull negative g because it would starve the oil pump for the propeller. If the hub has no oil pressure the propeller would drive full fine pitch thus increasing engine rpm. My guess is the propeller hub lost oil pressure somehow which drove the propeller to fine pitch which pushed the propeller rpm way above what it could handle and then the blades let loose and the engine went to its max rpm with no load on it.
The rev limiter on the engine should be set at rpm equivalent to prop rpm limit. So no way the engine can overspeed the prop. If he was flying fast and the governor failed and caused the prop to go to flat pitch, the prop could be passively driven to beyond its redline
Most aerobatic props work in reverse, or like a feathering hub if you will for this reason. Oil pressure to decrease pitch, so that if you do have oil starvation at the hub, you won't suddenly over-speed. Some other random aircraft have it that way as well.
Prop failure is not just a problem with experimental aircraft. My father had a prop disintegrate on an IO-520 which ripped the engine from the airframe. Luckily he had not yet taken off but still got hurt running off the end of the airstrip (about a 30 % downgrade into a gully - cropdusting....)
I find it extra tragic when a good pilot who did everything right and went out of his way to observe safety and best practices ended up not making it due to simple bad luck and circumstance. Sad
Something broke when overstresed, probably by execessive G forces on the part, due to his high performance "Zoom Climb" maneuver. That's what happens when being a test pilot. The real question is the part that broke a design deficiency, that will likely again fail when attempting that same maneuver, or a cumulative stressing mode which will require a lifetime limitation, then throw the part away requirement. Parts metallurgical engineering is why you pay $30 to $3,000 for a/c bolts, instead of going to the hardware store and getting the same size and thread for 30 cents to 3 bucks.
@@jakerabinz9411 30 to 3,000 for a bolt? lol. I built airplanes for 20 years and there are no $3,000 bolts in this airplane or any other unless you can show me an invoice for one.
This gentleman participated in the D day reenactment held yearly in Conneaut OH ,just east if Geneva. The event is coming up in the next week or two. He will be sorley missed. RIP
@@jaysmith1408 It's good that they can run on jet fuel. Also the low RPM helps. However, to get the most out of the high torque, you need variable pitch propellers.
I would guess the engine RPM surged because the hub failed and there was no longer force required to turn the now departed prop. Really a sad ending to a pillar of the experimental community.
If the hub fail, the propeller rpm doesn't increase. In this case the propeller rpm increased, causing the destruction of the propeller, so I think the hub doesn't was the cause.
Or the other way around. A propeller control or governor issue could have made the RPM surge beyond design rpm which would then have caused the propeller or its hub to fail.
@@gustavosegal5881 Not the propeller rpm; that of the engine. The hub quite likely failed, thus removing all load from the engine & allowing the sudden & significant increase.
What a sad news. I've met with the gentlemen a few years ago during a shop tour I've undertaken in order to assess the fabrication of their kits aircraft. Such a nice person is lost. My condolence to hos family and friends. RIP John.
As a glider pilot we are trained for low altitude breaks of an aero tow rope. One of the key factors that get drilled into you during training is to quickly find the best reachable landing area. A rope break under 200’ agl is considered too low to safely turn back to the airport. So landing ahead in some fashion is advised. Normally every airfield has around it a couple of options which can be better or worse depending on your altitude and wind. The brief satellite image of the airport in this case seemed to show some open fields in the area. Landing on a road is certainly more convenient for retrieval than a corn field but that road? So narrow with trees and power lines, yikes. Even in a non emergency situation that would have been a challenge. Maybe that was the only option. However, the point is to survive the landing first and foremost. Off airport landings are full of risks and the selection of the best place, quickly and under pressure is helped considerably by thinking about the best options before launch. I suspect power pilots don’t dwell on this subject as much as glider pilots do. But maybe some of the same instruction should be given. It can’t hurt.
Assuming he was passing north over the airfield when it happened, then staight ahead was the best option undoubtedly. Looks like a marshy area, followed by a water filled quarry, followed by the landfill. All of those look like better options for survivability. He was probably used to that narrow runway though and may have felt he could "thread the needle" on that side street. It's surprising he didn't stall on the 180 turn. You make a great point about knowing your options beforehand. Very little time for thought in those situations. A sad outcome indeed.
I’m sure this pilot had run through this scenario many times since it was his home airport. He actually accomplished the impossible turn but that just set him up for a perhaps impossible landing.
@@jimrankin2583 I'm not sure why he would have come up with such high risk options in that case. He was obviously a good pilot to have accomplished the impossible turn on what looks to be a high wing loaded plane, but it was all for naught with the landing site impediments. I take it this was not his own plane but someone elses? May have influenced his decision to try and save the aircraft.
Three people in my EAA chapter were flying behind auto engines (two Subaru and one Chevy). Two had off airport landings that substantially damaged the aircraft. One was able to return to the airport with a blown engine.
Unlike aero engines, auto engines aren't designed to be cruising at max power settings. Chevy LS engines cruise at around 35% power or 2000 - 3000 rpm.
@@maxmackinlay618I was just about to say that. They have a totally different duty cycle. They may have similar peak power but they are expected to it out it only for a small fraction of service life unlike aero engines that are designed to have very high outputs relative to their peak for most of the time.... It's a critical design factor.
That's awesome you posted one before you left for the airport! It was my absolute pleasure meeting you on the commute down South today. Have a great trip and I'll look forward to that new ceiling fan 😅.
@@toastrecon The NTSB report says he was trying to land on that road 1/4 mile west of the runway, and saw a car coming and changed his landing path to not impact the car. He didn't want to injure someone on the ground, and sadly was killed. A true aviator.
Yes, very sad. Roads are attractive when seen from above, but the combination of cars, signs, guard rails and power lines along roads can make them a dicy choice. Of course, when it's road or trees you gotta take the road.
I've been a huge fan of the LS engines since I bought my Z06 way back in 02... sixth gear on the interstate around eighty mph, it's just above idle rpm and gets 28-29 mpg. Drop down a few gears and it pulls hard to redline till 180 or so... incredible powerband even by todays standards. Seems like the perfect auto conversion on the surface, but for years Chevy had a tough time with drivetrains themselves, resorting to a crazy dual mass flywheel setup on the LT's to combat harmonics as a bandaid. There was an auto conversion featured in KitPlanes magazine years ago about a fellow name Tracy Crook(?) that detailed his Rx7 rotary conversion in a Vans RV that should be required reading for anyone considering such an undertaking. He gave great insight and detail from start to finish, including more than a few engine outs and near misses. I decided to pay the Lycoming tax and worry a little less haha
I could not get into any aircraft with a gearbox to the propeller...unless it is a turboprop designed from the ground up for aviation and nothing but aviation (as turboprops obviously are). There have always been good reasons as to why aero engines are designed to operate at the (up to) 2500 RPM approximate range.
hey Juan, the ding that goes along with your subscribe and turn on notifications graphic is very loud and high pitched (it’s actually quite painful to listen to!) would be great if that could be turned down or replaced!
Glad you’re back. I had to watch some guy named Holt, I think, to get updates on the Park fire. A few years ago I wouldn’t have given 2 hoots about the fire. Then I found you 🎸
@@B-System still, I would have asked for differentiation between just engine overspeed and prop overspeed. Engine over speed after failure is practically guaranteed. The absence of prop overspeed would be important to at what rpm the hub failed.
I worked for John at Titan Aircraft for almost 3 years. I worked on this plane on several occasions, as well as several others. Anything that had an LS on it was very nose-heavy.
@@PeacefulRallyCar-pw3csfind me a 6 cylinder that's substantially lighter than an LS and makes similar power, especially with all the turbo hardware. Won't get as good of millage for the same power level either, boosted motors run a richer mixture
@@zakn3954 most modern V6 are going to be lighter than a V8 by around 50-100lbs. When something is hanging from the nose of the craft every pound matters. An inline 6 is likely going to be just as heavy if not heavier than a V8, plus it going to stick out further ahead shifting the weight even more forward making it even more nose heavy.
@@madmax2069 lol look it up you will be surprised that most Modern v6's actually weigh the same or more than an all aluminum pushrod motor. Dohc, vvt, DOD, all that just mean more weight.
As usual fantastic breakdown and analysis. So tragic to see one of these go down and with the designer onboard. RIP sir, hoping they find a flaw along the way…
I own a Corvette with an earlier variant of this engine, the LS1. The LS3 is around 370 cu in and over 400 HP stock. They require a computer system to operate, unless the engine is very extensively modified. The computer in my car employs a "rev limiter" function, to avoid overspeeding the engine. I would imagine that if this LS3 were not modified to run without a computer, The engine could have been detuned to produce 300 HP, and rev limited to a value corresponding with the maximum safe propeller RPM. I am really curious about this engine installation, and what caused this failure. Godspeed to the pilot, and condolences to his family and friends.
We have no knowledge as to whether the engine speed was limited by the ECU. The fact that the engine overspeeded suggests that the engine speed was NOT limited by the ECU. The engine speed probably was limited only by the propeller pitch and pilot. It is easy to see now, with the benefit of hindsight, this was not sufficient redundancy. What now for all T51 owners?
If you lose oil pressure and the prop goes to fine, the engine should not over-rev (if the base pitch is set correctly). The prop blades were from whirlwind but the hub was made by Titan said someone familiar with the build.
He came so close to bringing it home but was faced with powerlines on the right and trees on the left. Clearly kept his cool and control of the aircraft right up to the end.
The owner pilot seemed very reasonable and quick to acknowledge the problems associated with making an auto engine work reliably in an aircraft. As he pointed out it’s the reduction units and other related system components that are more often the points of failure. I’ve always held the opinion that propeller reduction units are the stuff of industry. Just take a look inside the nose case of a big radial engine built in the forties. Very complicated, precision designed and manufactured planetary gears. I too like and fly almost exclusively experimental aircraft with the exception of my day job. But I never fly behind auto engines with experimental reduction units, belt drives or any of that stuff.
I love your channel and I don’t fly a plane, never have but I love planes. I am watching the planes around the fires. I started that because of your channel. Best wishes and be safe
Originally by hearing the 180 turn, I expected the typical stall. He darn near made it. Not much room to thread the needle. May have over corrected as it looks like he angled into the trees or just at minimum control speed and unable to correct in time. Such a sad moment for family, friends and fellow pilots. Regardless of experience, with aviation all it takes is just once…😢
@MrJeffcoley1 I thought the same thing. Also, someone said the landing gear was coming down. After a major failure I would just want to pancake in and hope to walk away from the landing.
@@jgalexander510 Yeah if you look at Google Maps there were really no good options. Even the fields dead ahead are small and surrounded by tall trees. The bigger roads all have power lines on one side and trees on the other. Even so, he almost made it.
Totally disagree, normally the hub failure would cause the surge in engine RPM, not the other way around. I'd default to harmonics, prop failure, hub failure, governor failure in that order before the engine given that it and the PSRU were completely in tact.
Terrible loss to the Experimental Aircraft community. A metallurgical examination of the prop hub should show where the failure started and how it prorogated through the hub. It will also show if there were any existing cracks in the hub. It will be interesting to know how many hours were on the hub. Auto engines are so tempting....
I'm going along with the others. The prop hub failed and that was what caused the increased engine rpm. Hopefully the NTSB will be able to confirm this by syncing the audio and video from the recording.
The propeller was a Whirlwind Aviation prop, a sister company of Whirlwind Propeller, in El Cajon, CA. Since about 2 1/2 years ago, the companies went separate ways.
Just wanted to make 2 observations that speak to a man I never knew's character: 1- He purposefully left his passenger on ground for one final check after maintenance and 2- my amateur eyes seem to see an evasive move at the end of his flight to avoid hitting a car with a passenger(s) in it.. knowing his own life would be in more danger. Minimum 2 lives saved as his final choices on Earth. Incredible. RIP Mr. Williams.
That's probably all true, but unfortunately it points to the mistake of his choice of where to land when there were better options available. If he had chosen better, rather than saving the plane or saving someone else's life, he would have been able to focus on saving his own. He knew the area well, so he knew what his options were. This was an option but far from ideal in the case of the plane, the other people and especially his own life.
@boneseyyl1060 idk. I'm not a pilot, but from the looks of things off Google maps, the road to the right running parallel to the runway (rt 218) doesn't look a while lot better to have made the attempt. Same goes for clay st (the road on the north side that runs perpendicular to the runway). Gotta keep in mind he was only a couple hundred feet up basically flying a glider. He didn't really have any other options other than those 3 roads I mentioned. None looked good imo.
@@joemalinak7410 Not a pilot either Joe, but I do know a little about flying. You are thinking that his only options are to land on a road.. And if saving the plane is the main concern you might be right. But the main concern has to be surviving the crash. And as you say, at that low of an altitude it is going to be a crash and not a landing. At that altitude and with no engine, his only real choice is to point the nose at the ground to maintain airspeed. Turning in any direction increases the risk of stalling or losing lift. In these situations real pilots will tell you to maintain as straight a heading as possible, pick the clearest open area ( and roads are not clear open areas) leave the gear up and fly the plane into the ground. The plane will slide and take some damage but more often than not the pilot will walk away. Trying to save the aircraft over your life is a poor choice. He had those choices directly in front of him but chose to turn and try the road. And it cost him everything, not just a plane.
@boneseyyl1060 no, the roads were not the only places i assumed he could potentially land. I totally get what you're saying, but if you look at the area, the only real open area that I could see was at the north end of the runway across the street. At least only open area that i would guess was big enough that he could reach gliding to. Right where he was probably making the 180 for the street that he attempted to land on and a few hundred feet directly below him. At least that's what it looks like viewing the area on Google maps. Maybe you see something I missed. But that was my TH-cam trained professional opinion 😁
@@joemalinak7410 Of course none of us really know what we would do in the that situation. Easy to sit with all the time in the world and decide. Having a plan beforehand helps and keep it simple. It's all you can really do. That open area in front was his best shot IMO. Sad that he won't be around to build more of those great looking planes.
I knew John. Great human being, and a great stick and rudder pilot. I own a Titan Tornado II SS, and we'd had a conversation about it and aerodynamics 2-3 weeks prior. You're right, Juan. As owners and operators of experimental aircraft, we're test pilots. And we do pay more attention to our aircraft. We have to. My preflights are far more involved in an Experimental. Thanks for the great content, Juan. My thoughts and prayers go to John, his family, and everyone his life touched through the decades.
So hard for me to understand anyone taking chances like this since my dad died in a plane crash And September 12September 12, 1992We have no details from that accident Nor have we found any trace of his body or his aircraft.His aircraft number was N6759 sierra. I will send you the NTSB Accident report number.Thank you so much For checking into this for me! H. Paul miller's daughter Paula joy miller.
Unusual for a composite blade prop hub to explode. There's a lot less mass and outward force Vs aluminium blades. I suppose once you go past 3000 rpm for any length of time any type of prop & hub is going to suffer. It's a horrible sound hearing a aero engine and prop go into overspeed, sort of sound you can't ignore.
Dang Juan!! What a loss!! I know this is hindsight, but already headed N., if had enough altitude, couldn't he have opted for a Lake Erie plane wash, w/wheels up water landing, swam away, & lived to fly again another day!!??
John correctly identified the mating of the engine to the prop controller as a "problem" and not a challenge. His passing is a great loss to the Experimental community of builders and pilots, but still, as with all aviation accidents, another cautionary tale for improved flight safety. (An-2 crash survivor)
I could easily understand an rpm surge if the gearbox had failed, unloading the engine. The gearbox could have subsequently locked up, causing shear forces within the prop hub to make it come apart, but the investigation determined the gearbox was intact, so that theory would be ruled out. Could the rpm surge have been due to a sudden pitch change of the propeller, caused by a failure inside the prop hub just before it came apart? Condolences to his family, and glad to see someone fastidious enough to test things before taking someone else up.
Been doing these since the 1980s? Damn. What a tragic loss. You can KNOW the risks, but they're still there. From Juan's reading of the summary, the driver of the car pulled over to the west as the pilot drifted east. Sounds like up to the end he was aware and trying to avoid other casualties. Godspeed, sir, and rest in peace.
I initially thought it was odd that the car driver pulled over on the wrong side of the road but given the presence of the power lines that may have been a case of excellent situational awareness on his part.
Sorry to hear about this...Looks like a nifty design; I saw a pair of these perform at a local (N. Ohio) airshow 10 years ago; both were powered by the Honda Odyssey 3.5 liter v-6, also rated at 300HP...
I have to wonder if there might have been a hairline crack or distortion in the gearbox casing causing something to pop out of alignment. Analysis of the video will be needed to determine if perhaps there was a gearbox oil leak before the engine went high RPM. Any inline screen filters will be important to check as well to see if metal particles provide clues as to what failed first inside.
Does the engine show evidence of overspeed? V8 exhaust note is unique among aviation engines so it would be hard to say that witness statements would be sufficient to know actual RPM. If in fact overspeed, was there an rpm limiting device? Did it fail? Was it set too high? A lot of open questions still on this one.
Another quality informative video! I would love to see Kohler or Wisconsin develop a lightweight Jet A fuel diesel that also uses "Speed of Air" pistons. Something that develops good power, good fuel economy, and develops power in the lower rpm range.
Well, it's a report from an eyewitness on the ground, so I would guess that he heard the engine rev before he saw the debris separate. Sound travel delay would put the overrev event even further before the debris event than he would have perceived.
The hub could partially fail (causing the blades to go flat pitch) unloading the engine enough to overspeed the prop which would then physically break apart the hub. Alternatively the hub could just have failed in some way and the overspeed happened after the blades came free.
Unless the engine suddenly found a way to make a LOT more hp, it sounds like the prop pitch had to have suddenly gone to a very fine position, unloading the engine while it's throttle was mostly open. Failed prop governor, perhaps?
Why they don't design and install a governor on those engines. May not be failure free, but adds a layer of protection. Saddened for the loss of life, it's a sobering event to see this kind of thing happening. Thank you for bringing us this video
Looks like a landfill to the north. Questionable terrain, but no trees. Wonder if he should have tried to put it down on the landfill straight ahead instead of turning into a tree-lined street.
They have a real company backing them that’s spent thousands of hours on R&D to get them to work properly. Rotax and the Austro motors aren’t even remotely comparable to the applications on 99% of auto conversion homebuilts.
Sounds like he almost made it down. Every time I hear about the loss of an experienced pilot, it makes me think about what I could do to avoid a similar fate. Thats why this channel is so valuable.
@blancolirio I myself have an LS3 powered T51, nothing wrong with the automotive conversion. After Johns accident I believe I found what may have caused the catastrophic result which I’m now open to sharing. The Link ECU used has certain parameter settings, one being the Engine RPM limit. After thorough investigation, the ECU had the ENG RPM parameter set to 4500 however, it was not turned on. The design fault here has the throttle linkage set to WOT, essentially allowing the engine to go to 6600rpm. Put two and two together, throttle linkage break lead to full WOT, no ECU protection, governor failed to govern due to a high rpm acceleration exceeding the rate at which the governor could manage the load. This in turn caused the prop to swing at 3500rpm. Centrifugal load tore the hub apart. I contacted all Link ECU owners of the T51 LS3 and all found the same issue (ECU parameters set but not turned on). A simple fix but a tragic loss to find the reason behind the cause of the accident.
My only question I may have missed if you mentioned it was.....was the prop the type with a variable pitch...a loss of pitch control would be the only way it could have over revved before the loss of the blades...
RPM could not surge so rapidly without loosing the load on the engine . So possibly the connection was broken inside the hub which caused the detachment of the blades simultaneously causing the over revving heard by witnesses. The oil spray on the underside of the aircraft could have been from detonating the LS engine .
Prop first or engine first? Read the report. “When the airplane pitched up, he heard the engine go to a “super high RPM” and then the “entire prop hub shatters.” He observed several parts and pieces explode from the nose section of the airplane, and the engine noise subsequently went silent.” This one was close to home. Condolences to friends and family.
I wonder if he clipped the tree because he turned slightly to the left to avoid the oncoming car. The driver of the car reported seeing him coming head on and pulling off the road to his left. They each went left to avoid a collision.
sorry for the lost of an experienced EAA pilot. perhaps the engine didn't need the added oil? Would like more info on the LS3's condition (I'm a Vette owner, it's a great engine) I also don't understand why he opted for a residential street with trees ... rather than the runway right behind him with apparently plenty of energy. Nice Coverage Juan. Thank you.
Fuel injected engines like the GM LS engine are computer controlled that have adjustable Rev limiting features. There’s no way the engine could over speed the set limit under any circumstances, especially in this case while under load. The engine hit the set limit RPM only after the load (the gearbox and propeller) was was suddenly disconnected. What was seen and heard was the failure of the gearbox or prop hub failing that caused the engine to rev to the set limit and the pilot then pulling off the throttle. As a caveat with my statement is that I don’t know what ECU is used in this application. If not a GM supplied unit, pretty much all aftermarket controllers offer the same functionality as GM units in automotive applications. Meaning RPM control would be the same. Additionally, many aftermarket ECU’s or PCM’s offer (as do most GM units) transmission input and output shaft speed sensors that can sense slippage. Some also offer driveshaft speed sensors, all of which could easily be adapted to gearbox and propeller speed monitoring that will instantly reduce engine power output or cut power to the ignition coils when shaft speeds exceed parameters.
I'm curious about the reported oil spray. I wonder if they will be able to separate the oil that certainly sprayed out during/after the crash from any that might have been in-flight and part of a loss of oil pressure to the hub. I think the comments about loss of oil pressure leading to a prop feather are onto something. But perhaps there was a mechanical malfunction (leak) that contributed to the loss of pressure. If the thing was already "low on oil", was it due to oil consumption or was it possibly losing some oil under pressure from somewhere? I'm not sure what the oil consumption norms are for the LS engine. Would be interesting to hear about if they do a teardown of the engine. Perhaps debris in the oil pickup tube? Certainly this has been addressed, but in an LS, I wonder where is the oil pickup tube in relation to the sump, especially when doing a high-G pitch up maneuver. Also, not sure which generation of LS engine was used, but I know from following some hot-rodder youtube channels that there is an aftermarket oil tube pickup brace guys like to add to strengthen the attachment, as from the factory there is only one bolt holding it into the pump instead of two. Perhaps things like this were a failure point during a high-G maneuver which was overlooked as the engine was never designed for this type of application. I admire doing these kind of engine swaps. Takes some serious engineering. But certainly there are all kinds of issues like this that would be hard to track down without encountering an unfortunate failure.
My feeling is the urge to save the airplane was overwhelming, witness the turnback and lowering the gear. I agree, straight ahead into a field was doable, he had the advantage of no drag from a windmilling 4 blade prop, and a bunch of altitude to work with. Very sad. Similar outcome to the Howard Hughes racer replica accident a few years ago, prop governor failure and instead of using the chute, pilot tried to save the airplane by landing into rough terrain.
RIP . condolences to family & friends. what’s the procedure for a lost prop governor , while airborne ? 1. throttle to idle 2 . climb to slow down windmilling prop 3. ??? deadstick . i’m just guessing. only heard of situations like this from fellow aviators…
I can certainly understand the attraction of flying, but as a non-pilot observer reading the almost daily barrage of ghastly fatal GA incidents that include the most proficient and experienced pilots within your community.... bless y'all, you have much bigger balls than I do.
That road would not have been my first choice for a forced landing. Looking at the surrounding area there was a field directly in front of him, with a couple more to the east.
This time of year, the field is probably full of corn. It might have been safer than a narrow tree-lined road, but it might not have seemed safer in the split-second needed to make the decision.
No, to be clear and as presented in the video. The prop hub failure was PRECEEDED by a gross PROP OVERSPEED.
@@blancolirio What would cause the overspeed? A sudden increase in air-fuel mixture into the cylinders? Is that possible? Is the engine supercharged or turbo supercharged?
Or a flattening of propeller pitch?
I mean, we don’t know; but what are the possible causes?
I don't think we can read too much into that. The overspeed might have been preceded by a prop control failure, the nature of which we don't know, therefore we don't know the possible consequences of such a failure. Those consequences might include blade separation independent of prop speed.
Not a pilot, but I take prop full forward to mean pitch was was correct, not flat.
@@sirbike That referred to the prop control lever in the cockpit, not the condition of the prop itself.
Is that conclusion (which came first) being drawn from eyewitness testimony? Eyewitness testimony is very unreliable and an overspeed from hub failure seems WAY more plausible than, say, he hit the nitrous boost or something.
Damn that sucks, met him a few times and really enjoyed talking to him about the Titans. RIP buddy
The mechanical failure made an emergency landing urgently necessary, but it was the lack of a good place for that landing which made this a fatal crash. The solo post-maintenance test flight saved the planned passenger from serious injury or death, which demonstrates that test piloting is both dangerous and necessary. RIP.
Hats of to the pilot for check flying the plane before he took the other pilot up. RIP.
You mean hats off?
@@slappy8941Most people with common sense know what he meant.
@@slappy8941 What do you gain by pointing out one of the most common types in the universe?
@@smugfrog8111 What do you gain by complaining about it, especially without proofreading?
@@gandydancer9710 Haahaha! OK, That is funny. I literally typo'd "Typo"
However, still. My question is valid, yours is not.
Very sad loss for his family and the experimental aircraft community.
I met this guy last year and saw this plane at the Cleveland Interational Air Show, he was really nice and answered a bunch of questions about the plane, homebuilding, his different kits, and business. Really sad. RIP sir.
Thanks Juan, another excellent report. My sincere condolences to the pilot's friends and family.
I would observe, as an engine guy - that any time I see or hear an engine overspeed suddenly - especially in a condition where one would normally expect the load to be increasing,
my experience causes me to suspect that the load suddenly came off the engine.
It is difficult to overspeed a fully loaded engine.
Perhaps, a pitch control failure, unloading the engine? I will be waiting to hear what they end up determining the root cause of the overspeed was.
I concur.....if it had a variable pitch prop that's about the only was she's gonna do a freewheel redline rev...
The sequence was most likely, that the hub failed, then the blades separated, then the revs went through the red line. A ground observer would see the blades separate first, then maybe 3 seconds later would hear the bang and then the revs rise.
@@hiscifi2986 ...the blades feathered flat n that let the motor go 9000 n then the hub failed in that order....
Since over-speeding is a major concern, I'd think there would be a rev limiter set to a value within the normal operating parameters. My guess is something failed prior to the rev increase that caused the revs to rise even with rev limiter intervention.
@@notter59 blades went flat
John was very kind to me when I was a line guy at the Geauga County Airport 7G8.. many years ago. This one was hard to see
I don’t know why these people risk their lives in these crappy aircraft
@BlingtingSam I have been almost killed 3 times by million dollar aircrafts. One wich was a total loss due to engine failure 300 hours on the airframe . Their most concern, not " crappy " aircraft, and you, sir, are disrespect and uneducated. Have a nice day.
Well there is no disputing something crapped out. The guy designed it, guy built it, guy test flew it, and understandably found a lethal limitation. Better he then one of his clients. Who if it were they who died instead of him, you can bet your ass the lawyers would be making his life hell. RIP to him or whatever comes next. He knew the risk, he died trying to push the design envelope to see where it fails. same as every other Experimental plane. He obviously loved what he was doing. Like helicopter pilots. More die flying in a helicopter before reaching 3000 hours in type, than get beyond that. Cause they love to fly helicopters. I know of a ' Nam Cobra Pilot, who in civillian life flew 315 Lamas . Had 1000's of hours. After his second "bent bird" incident over his decades, he hung it up. He knew the next time would be his last time, and had a family member needing continuing care. Also flew with a very famous jillions of hours motion picture helicopter stunt pilot. Nice guy, very professional, and detailed emphatically the purpose of the mission, and what the cameraperson limitations are, before flight. Later he died doing what he loved. Flight is always risky business.
@jakerabinz9411 and what risk have you financed?
I had a 310P and had to rebuild the props. Learned way more than I wanted to know. The hubs keep the props from centrifugal forces exceeding 20 tons each if I remember right. When you have one fail it is catastrophic. It can rip the engine right out of the frame. Condolences to him, his family and friends.
Centrifugal force is a misnomer. It does not exist as a force in the realities of physics. Centripetal force is a real force that keeps an object moving in a circle, while centrifugal force is an apparent force that pushes an object away from the center of a circle:
Centripetal force
A real force that acts towards the center of a circle, or the axis of rotation, to keep an object moving in a circle.
@@danblumel The difference is mostly philosophical here, we are talking about the stresses upon the propeller hub. It also depends on your reference frame, which for the propeller hub is spinning at a few 1000 RPM …
How about you tackle a force being expressed in units of inertial mass (20 tons) instead of units of force (about 196,000,000 Newton)?
@@danblumelThe centrifugal force is the problem because it pulls from center. Ie the hub being center and the ends of the props being the outer circumference. When a prop fails the hub is pulled from center from said force. The reason it is centrifugal is because of the imparted rotation from the connecting rods to the crank to the hub. Making it a force that wants to push away from center when a prop fails.
@@danblumelcentrifugal force is one of several false forces that are actually inertial tendencies but may as well not be for practical reasons
As long as we all understand that "centrifugal" refers only to the direction of and not the nature or origin of the force. My work here is done. 😄
Not sure if it applies to this engine and gear box but I remember talking to someone about these LS automotive conversions. One of the major drawbacks was you couldn’t pull negative g because it would starve the oil pump for the propeller. If the hub has no oil pressure the propeller would drive full fine pitch thus increasing engine rpm. My guess is the propeller hub lost oil pressure somehow which drove the propeller to fine pitch which pushed the propeller rpm way above what it could handle and then the blades let loose and the engine went to its max rpm with no load on it.
That's an interesting limitation and would seem to fit the nature of the failure. I'll be very interested to hear the final report on this.
Yep. The witness CLAIMS he heard the over-speed sound before the failure, and since sound would be delayed and visual was instantaneous...
@joeneu your comment is worth reading and considering
The rev limiter on the engine should be set at rpm equivalent to prop rpm limit. So no way the engine can overspeed the prop. If he was flying fast and the governor failed and caused the prop to go to flat pitch, the prop could be passively driven to beyond its redline
Most aerobatic props work in reverse, or like a feathering hub if you will for this reason. Oil pressure to decrease pitch, so that if you do have oil starvation at the hub, you won't suddenly over-speed. Some other random aircraft have it that way as well.
Nice coverage as usual Juan, thanks for what you do.
Prop failure is not just a problem with experimental aircraft. My father had a prop disintegrate on an IO-520 which ripped the engine from the airframe. Luckily he had not yet taken off but still got hurt running off the end of the airstrip (about a 30 % downgrade into a gully - cropdusting....)
I find it extra tragic when a good pilot who did everything right and went out of his way to observe safety and best practices ended up not making it due to simple bad luck and circumstance. Sad
Yep. General aviation in an experimental plane is Russian roulette 😅
@@BlingtingSam What?
But that's not what happened at all.
Something broke when overstresed, probably by execessive G forces on the part, due to his high performance "Zoom Climb" maneuver. That's what happens when being a test pilot. The real question is the part that broke a design deficiency, that will likely again fail when attempting that same maneuver, or a cumulative stressing mode which will require a lifetime limitation, then throw the part away requirement. Parts metallurgical engineering is why you pay $30 to $3,000 for a/c bolts, instead of going to the hardware store and getting the same size and thread for 30 cents to 3 bucks.
@@jakerabinz9411 30 to 3,000 for a bolt? lol.
I built airplanes for 20 years and there are no $3,000 bolts in this airplane or any other unless you can show me an invoice for one.
This gentleman participated in the D day reenactment held yearly in Conneaut OH ,just east if Geneva. The event is coming up in the next week or two. He will be sorley missed. RIP
Thank you Juan! So sad for this loss of life.
The Diamond DA42 does very well with its Mercedes Benz Turbo Diesel Engines. Certificated and everything. Worked on them a lot.
Was curious about diesels. They run fairly slowly, with gobs of torque.
I won't call that well if you have been following it since the Thielert days.
@@jaysmith1408 It's good that they can run on jet fuel. Also the low RPM helps. However, to get the most out of the high torque, you need variable pitch propellers.
@@MetaView7 thats when they first came out. I actually prefered Thielerts over Austros.
@@markotrieste they used constant speed. Pretty efficient still.
I would guess the engine RPM surged because the hub failed and there was no longer force required to turn the now departed prop. Really a sad ending to a pillar of the experimental community.
My guess also. Prop hub was probably cracked long before it broke. Stress crack, bad metal, something.
9:00 could one calculate the prop rpm with those frames?
If the hub fail, the propeller rpm doesn't increase. In this case the propeller rpm increased, causing the destruction of the propeller, so I think the hub doesn't was the cause.
Or the other way around. A propeller control or governor issue could have made the RPM surge beyond design rpm which would then have caused the propeller or its hub to fail.
@@gustavosegal5881 Not the propeller rpm; that of the engine.
The hub quite likely failed, thus removing all load from the engine & allowing the sudden & significant increase.
So sad. The EAA community HAS suffered a great loss. Condolences to his family. R.I.P.
What a sad news. I've met with the gentlemen a few years ago during a shop tour I've undertaken in order to assess the fabrication of their kits aircraft. Such a nice person is lost. My condolence to hos family and friends. RIP John.
As a glider pilot we are trained for low altitude breaks of an aero tow rope. One of the key factors that get drilled into you during training is to quickly find the best reachable landing area. A rope break under 200’ agl is considered too low to safely turn back to the airport. So landing ahead in some fashion is advised.
Normally every airfield has around it a couple of options which can be better or worse depending on your altitude and wind.
The brief satellite image of the airport in this case seemed to show some open fields in the area. Landing on a road is certainly more convenient for retrieval than a corn field but that road? So narrow with trees and power lines, yikes. Even in a non emergency situation that would have been a challenge. Maybe that was the only option.
However, the point is to survive the landing first and foremost. Off airport landings are full of risks and the selection of the best place, quickly and under pressure is helped considerably by thinking about the best options before launch.
I suspect power pilots don’t dwell on this subject as much as glider pilots do. But maybe some of the same instruction should be given. It can’t hurt.
Assuming he was passing north over the airfield when it happened, then staight ahead was the best option undoubtedly. Looks like a marshy area, followed by a water filled quarry, followed by the landfill. All of those look like better options for survivability. He was probably used to that narrow runway though and may have felt he could "thread the needle" on that side street. It's surprising he didn't stall on the 180 turn.
You make a great point about knowing your options beforehand. Very little time for thought in those situations. A sad outcome indeed.
I’m sure this pilot had run through this scenario many times since it was his home airport. He actually accomplished the impossible turn but that just set him up for a perhaps impossible landing.
@@jimrankin2583 I'm not sure why he would have come up with such high risk options in that case. He was obviously a good pilot to have accomplished the impossible turn on what looks to be a high wing loaded plane, but it was all for naught with the landing site impediments. I take it this was not his own plane but someone elses? May have influenced his decision to try and save the aircraft.
@@boneseyyl1060This was his own plane, he built it himself and he offers/offered the kit to build the plane to others.
I commented the same thing then read to find another similar comment....I don't understand either the field was right there!!!
Three people in my EAA chapter were flying behind auto engines (two Subaru and one Chevy). Two had off airport landings that substantially damaged the aircraft. One was able to return to the airport with a blown engine.
Unlike aero engines, auto engines aren't designed to be cruising at max power settings. Chevy LS engines cruise at around 35% power or 2000 - 3000 rpm.
💪
KXLL 8 years ago Corvair engine plane crashed pilot lived never flew again that plane had several engine problems
How many experimental planes are flying with the good old VW engines that powered the Beetle?
@@maxmackinlay618I was just about to say that. They have a totally different duty cycle. They may have similar peak power but they are expected to it out it only for a small fraction of service life unlike aero engines that are designed to have very high outputs relative to their peak for most of the time.... It's a critical design factor.
That's awesome you posted one before you left for the airport! It was my absolute pleasure meeting you on the commute down South today. Have a great trip and I'll look forward to that new ceiling fan 😅.
Thanks Greg!
Dang, bad luck on landing! He almost made the glide in.
Yeah, he did everything he could, just clipped a tree at a very bad time. RIP and condolences to the family and his friends.
Wonder if his vision was obscured by oil film on windscreen?
@@toastrecon The NTSB report says he was trying to land on that road 1/4 mile west of the runway, and saw a car coming and changed his landing path to not impact the car. He didn't want to injure someone on the ground, and sadly was killed. A true aviator.
Yes, very sad. Roads are attractive when seen from above, but the combination of cars, signs, guard rails and power lines along roads can make them a dicy choice. Of course, when it's road or trees you gotta take the road.
I've been a huge fan of the LS engines since I bought my Z06 way back in 02... sixth gear on the interstate around eighty mph, it's just above idle rpm and gets 28-29 mpg. Drop down a few gears and it pulls hard to redline till 180 or so... incredible powerband even by todays standards. Seems like the perfect auto conversion on the surface, but for years Chevy had a tough time with drivetrains themselves, resorting to a crazy dual mass flywheel setup on the LT's to combat harmonics as a bandaid.
There was an auto conversion featured in KitPlanes magazine years ago about a fellow name Tracy Crook(?) that detailed his Rx7 rotary conversion in a Vans RV that should be required reading for anyone considering such an undertaking. He gave great insight and detail from start to finish, including more than a few engine outs and near misses. I decided to pay the Lycoming tax and worry a little less haha
I could not get into any aircraft with a gearbox to the propeller...unless it is a turboprop designed from the ground up for aviation and nothing but aviation (as turboprops obviously are). There have always been good reasons as to why aero engines are designed to operate at the (up to) 2500 RPM approximate range.
hey Juan, the ding that goes along with your subscribe and turn on notifications graphic is very loud and high pitched (it’s actually quite painful to listen to!) would be great if that could be turned down or replaced!
I second this!
I agreed.. i was wondering this also
I agree, I’d be great if he could change it
I'll pass that along to the intern...."Kellen!"...;-)
Yeah, it startled me.
Glad you’re back. I had to watch some guy named Holt, I think, to get updates on the Park fire. A few years ago I wouldn’t have given 2 hoots about the fire. Then I found you 🎸
Holt Hanley and Mark Finan both do a good job picking up the slack for Juan.
I wonder if the high-rpm condition came after the failure since the sound takes a second +/- to get to the witness.
The sound was reported before the prop departed, so if that's accurate that's against this hypothesis.
Oh my God! a concept in nature about things we know versus the things people claim to have seen and heard. Winner Winner! Chicken Dinner!
@@B-System still, I would have asked for differentiation between just engine overspeed and prop overspeed. Engine over speed after failure is practically guaranteed. The absence of prop overspeed would be important to at what rpm the hub failed.
@@bendeleted9155I'm sure whoever made that determination did so after watching the video recording.
@@csolivais1979 good point. We didn't get to see that.
Thanks for creating an informative video about what led to the crash. It's a terrible loss to the flying community. RIP, John.
I worked for John at Titan Aircraft for almost 3 years. I worked on this plane on several occasions, as well as several others. Anything that had an LS on it was very nose-heavy.
@@PeacefulRallyCar-pw3csfind me a 6 cylinder that's substantially lighter than an LS and makes similar power, especially with all the turbo hardware. Won't get as good of millage for the same power level either, boosted motors run a richer mixture
@@zakn3954 yes surely someone has thought of it already
@@zakn3954The T-51 flew with Suzuki and Honda V6s, both weighed significantly less (100 pounds or more).
@@zakn3954 most modern V6 are going to be lighter than a V8 by around 50-100lbs. When something is hanging from the nose of the craft every pound matters.
An inline 6 is likely going to be just as heavy if not heavier than a V8, plus it going to stick out further ahead shifting the weight even more forward making it even more nose heavy.
@@madmax2069 lol look it up you will be surprised that most Modern v6's actually weigh the same or more than an all aluminum pushrod motor. Dohc, vvt, DOD, all that just mean more weight.
As usual fantastic breakdown and analysis. So tragic to see one of these go down and with the designer onboard. RIP sir, hoping they find a flaw along the way…
I own a Corvette with an earlier variant of this engine, the LS1. The LS3 is around 370 cu in and over 400 HP stock. They require a computer system to operate, unless the engine is very extensively modified. The computer in my car employs a "rev limiter" function, to avoid overspeeding the engine. I would imagine that if this LS3 were not modified to run without a computer, The engine could have been detuned to produce 300 HP, and rev limited to a value corresponding with the maximum safe propeller RPM. I am really curious about this engine installation, and what caused this failure. Godspeed to the pilot, and condolences to his family and friends.
I would think it still had an ECU, probably a custom built and programmed one.
We have no knowledge as to whether the engine speed was limited by the ECU.
The fact that the engine overspeeded suggests that the engine speed was NOT limited by the ECU.
The engine speed probably was limited only by the propeller pitch and pilot.
It is easy to see now, with the benefit of hindsight, this was not sufficient redundancy.
What now for all T51 owners?
Good report JB. So sad a story. Using something for not what it was intended for obviously has inherent risks.
If you lose oil pressure and the prop goes to fine, the engine should not over-rev (if the base pitch is set correctly).
The prop blades were from whirlwind but the hub was made by Titan said someone familiar with the build.
Also if we start putting ecms on airplane engines then we could also have fuel cutoffs to prevent overspeeding like car engines have
@@Heatherder They do and it did
He came so close to bringing it home but was faced with powerlines on the right and trees on the left. Clearly kept his cool and control of the aircraft right up to the end.
The owner pilot seemed very reasonable and quick to acknowledge the problems associated with making an auto engine work reliably in an aircraft. As he pointed out it’s the reduction units and other related system components that are more often the points of failure. I’ve always held the opinion that propeller reduction units are the stuff of industry. Just take a look inside the nose case of a big radial engine built in the forties. Very complicated, precision designed and manufactured planetary gears. I too like and fly almost exclusively experimental aircraft with the exception of my day job. But I never fly behind auto engines with experimental reduction units, belt drives or any of that stuff.
I love your channel and I don’t fly a plane, never have but I love planes. I am watching the planes around the fires. I started that because of your channel. Best wishes and be safe
Thanks Juan, my condolences to his family.
When the hub failed the engine load went to zero, which would allow it to suddenly overspeed. Not the other way around.
I agree. This is my theory as well
You can't know that.
Could also be runaway rpm -> hub failure -> even higher rpm for a few seconds -> down to idle.
@@--SPQR-- Yes agreed, could have been either. Still unanswered questions.
@@--SPQR--the issue with that would be for excessive RPM you'd also need loads of power.
@@kain0m Not if it was an adjustable or constant-speed propeller that failed.
Originally by hearing the 180 turn, I expected the typical stall. He darn near made it. Not much room to thread the needle. May have over corrected as it looks like he angled into the trees or just at minimum control speed and unable to correct in time.
Such a sad moment for family, friends and fellow pilots.
Regardless of experience, with aviation all it takes is just once…😢
Those utility poles on the right side make this a mighty narrow landing space to shoot for. Bummer that there wasn’t a safer space to shoot for.
I wonder why he didn't just go straight ahead. Looks like lots of open fields, and a lake.
@MrJeffcoley1 I thought the same thing. Also, someone said the landing gear was coming down. After a major failure I would just want to pancake in and hope to walk away from the landing.
@MrJeffcoley1 open fields, wow, you are correct, do not make the impossible turn!
@@jgalexander510 Yeah if you look at Google Maps there were really no good options. Even the fields dead ahead are small and surrounded by tall trees. The bigger roads all have power lines on one side and trees on the other. Even so, he almost made it.
Thanks for the critiques Juan.
Totally disagree, normally the hub failure would cause the surge in engine RPM, not the other way around. I'd default to harmonics, prop failure, hub failure, governor failure in that order before the engine given that it and the PSRU were completely in tact.
I agree with you
Ditto
Governor failure or not was irrelevant after the hub had exploded
Terry Kronk’s scale P51 with a detuned LS3 and 4 blade suffered a somewhat similar but gearbox shaft failure in 2012. RIP we all miss you brother.
Terrible loss to the Experimental Aircraft community. A metallurgical examination of the prop hub should show where the failure started and how it prorogated through the hub. It will also show if there were any existing cracks in the hub. It will be interesting to know how many hours were on the hub. Auto engines are so tempting....
I'm going along with the others. The prop hub failed and that was what caused the increased engine rpm. Hopefully the NTSB will be able to confirm this by syncing the audio and video from the recording.
So sad! I can't believe I didn't hear about this until now. I live close enough that my house was on the map.
The propeller was a Whirlwind Aviation prop, a sister company of Whirlwind Propeller, in El Cajon, CA. Since about 2 1/2 years ago, the companies went separate ways.
Just wanted to make 2 observations that speak to a man I never knew's character: 1- He purposefully left his passenger on ground for one final check after maintenance and 2- my amateur eyes seem to see an evasive move at the end of his flight to avoid hitting a car with a passenger(s) in it.. knowing his own life would be in more danger.
Minimum 2 lives saved as his final choices on Earth. Incredible. RIP Mr. Williams.
That's probably all true, but unfortunately it points to the mistake of his choice of where to land when there were better options available. If he had chosen better, rather than saving the plane or saving someone else's life, he would have been able to focus on saving his own. He knew the area well, so he knew what his options were. This was an option but far from ideal in the case of the plane, the other people and especially his own life.
@boneseyyl1060 idk. I'm not a pilot, but from the looks of things off Google maps, the road to the right running parallel to the runway (rt 218) doesn't look a while lot better to have made the attempt. Same goes for clay st (the road on the north side that runs perpendicular to the runway).
Gotta keep in mind he was only a couple hundred feet up basically flying a glider. He didn't really have any other options other than those 3 roads I mentioned. None looked good imo.
@@joemalinak7410 Not a pilot either Joe, but I do know a little about flying. You are thinking that his only options are to land on a road.. And if saving the plane is the main concern you might be right. But the main concern has to be surviving the crash. And as you say, at that low of an altitude it is going to be a crash and not a landing. At that altitude and with no engine, his only real choice is to point the nose at the ground to maintain airspeed. Turning in any direction increases the risk of stalling or losing lift. In these situations real pilots will tell you to maintain as straight a heading as possible, pick the clearest open area ( and roads are not clear open areas) leave the gear up and fly the plane into the ground. The plane will slide and take some damage but more often than not the pilot will walk away. Trying to save the aircraft over your life is a poor choice.
He had those choices directly in front of him but chose to turn and try the road. And it cost him everything, not just a plane.
@boneseyyl1060 no, the roads were not the only places i assumed he could potentially land. I totally get what you're saying, but if you look at the area, the only real open area that I could see was at the north end of the runway across the street. At least only open area that i would guess was big enough that he could reach gliding to. Right where he was probably making the 180 for the street that he attempted to land on and a few hundred feet directly below him. At least that's what it looks like viewing the area on Google maps. Maybe you see something I missed. But that was my TH-cam trained professional opinion 😁
@@joemalinak7410 Of course none of us really know what we would do in the that situation. Easy to sit with all the time in the world and decide. Having a plan beforehand helps and keep it simple. It's all you can really do. That open area in front was his best shot IMO. Sad that he won't be around to build more of those great looking planes.
Thanks for another but sad report.Condolences to his family,safe flights mate,🙏🙏👋👋👍🇦🇺
I knew John. Great human being, and a great stick and rudder pilot. I own a Titan Tornado II SS, and we'd had a conversation about it and aerodynamics 2-3 weeks prior. You're right, Juan. As owners and operators of experimental aircraft, we're test pilots. And we do pay more attention to our aircraft. We have to. My preflights are far more involved in an Experimental. Thanks for the great content, Juan. My thoughts and prayers go to John, his family, and everyone his life touched through the decades.
But sometimes people get complacent.
A good friend, high time etc, on a short local flight ran his RV out of gas and died.
@@hotrodray6802 Agreed. I see it a lot, and all it takes is someone interrupting you during a preflight. Sorry for the loss of your friend.
I love all the respectful discussions we can have in this community, and disagree respectfully. Thanks, Guys.
So hard for me to understand anyone taking chances like this since my dad died in a plane crash And September 12September 12, 1992We have no details from that accident Nor have we found any trace of his body or his aircraft.His aircraft number was N6759 sierra. I will send you the NTSB Accident report number.Thank you so much For checking into this for me! H. Paul miller's daughter Paula joy miller.
Unusual for a composite blade prop hub to explode. There's a lot less mass and outward force Vs aluminium blades. I suppose once you go past 3000 rpm for any length of time any type of prop & hub is going to suffer. It's a horrible sound hearing a aero engine and prop go into overspeed, sort of sound you can't ignore.
Wow that’s sad 😔
I mean, at least he didn’t die in an old age home, but still…
I’ve seen a couple T-51s in South Africa.
Dang Juan!! What a loss!! I know this is hindsight, but already headed N., if had enough altitude, couldn't he have opted for a Lake Erie plane wash, w/wheels up water landing, swam away, & lived to fly again another day!!??
Thanks for the detailed report on the world of experimental aircraft.
John correctly identified the mating of the engine to the prop controller as a "problem" and not a challenge. His passing is a great loss to the Experimental community of builders and pilots, but still, as with all aviation accidents, another cautionary tale for improved flight safety. (An-2 crash survivor)
Dam it man .....he did very well but the road was too narrow RIP
Well done Juan. Answers coming I hope!
I could easily understand an rpm surge if the gearbox had failed, unloading the engine. The gearbox could have subsequently locked up, causing shear forces within the prop hub to make it come apart, but the investigation determined the gearbox was intact, so that theory would be ruled out. Could the rpm surge have been due to a sudden pitch change of the propeller, caused by a failure inside the prop hub just before it came apart? Condolences to his family, and glad to see someone fastidious enough to test things before taking someone else up.
Yep, most likely pitch control failed, blades went to flat pitch and allowed the overspeed which caused the hub to fail.
Sad to hear about his crash. I bought a Titan Tornado II from him back in the 90’s after taking a demo flight in one with him.
Been doing these since the 1980s? Damn. What a tragic loss. You can KNOW the risks, but they're still there.
From Juan's reading of the summary, the driver of the car pulled over to the west as the pilot drifted east. Sounds like up to the end he was aware and trying to avoid other casualties.
Godspeed, sir, and rest in peace.
I initially thought it was odd that the car driver pulled over on the wrong side of the road but given the presence of the power lines that may have been a case of excellent situational awareness on his part.
Sorry to hear about this...Looks like a nifty design; I saw a pair of these perform at a local (N. Ohio) airshow 10 years ago; both were powered by the Honda Odyssey 3.5 liter v-6, also rated at 300HP...
It needs to make that power at the required 2,000- 3,000 engine rpm as discussed at 1:30.
I have to wonder if there might have been a hairline crack or distortion in the gearbox casing causing something to pop out of alignment. Analysis of the video will be needed to determine if perhaps there was a gearbox oil leak before the engine went high RPM. Any inline screen filters will be important to check as well to see if metal particles provide clues as to what failed first inside.
The P-51 never met Mr. Martin Baker. But Mr. Baker is the only one who can save you from an engine out deadstick at 300 ft over unforgiving terrain.
The only problem with that is to keep the seats live. It would cost more than the airplane so unless you’re a millionaire it’s unrealistic.
Was this a variable-pitch prop? The engine speed surge could have been the pitch mechanism going to flat pitch while the engine was under load.
Does the engine show evidence of overspeed? V8 exhaust note is unique among aviation engines so it would be hard to say that witness statements would be sufficient to know actual RPM. If in fact overspeed, was there an rpm limiting device? Did it fail? Was it set too high?
A lot of open questions still on this one.
Thanks!
Juan, you and Sal should do a joint utube stream sometime. You both are excellent storytellers.
Another quality informative video! I would love to see Kohler or Wisconsin develop a lightweight Jet A fuel diesel that also uses "Speed of Air" pistons. Something that develops good power, good fuel economy, and develops power in the lower rpm range.
Very sad story.
How do you know that the engine surged in RPM first and THEN the hub failed. Why not the other way around? Thank you!
Well, it's a report from an eyewitness on the ground, so I would guess that he heard the engine rev before he saw the debris separate. Sound travel delay would put the overrev event even further before the debris event than he would have perceived.
I think from the video they concluded that it was an initial surge and a subsequent failure.
Because the propeller was destroyed by high rpm
EDIT: Not just an eyewitness report, the eyewitness recorded video.
The hub could partially fail (causing the blades to go flat pitch) unloading the engine enough to overspeed the prop which would then physically break apart the hub. Alternatively the hub could just have failed in some way and the overspeed happened after the blades came free.
Unless the engine suddenly found a way to make a LOT more hp, it sounds like the prop pitch had to have suddenly gone to a very fine position, unloading the engine while it's throttle was mostly open. Failed prop governor, perhaps?
Why they don't design and install a governor on those engines. May not be failure free, but adds a layer of protection. Saddened for the loss of life, it's a sobering event to see this kind of thing happening.
Thank you for bringing us this video
Looks like a landfill to the north. Questionable terrain, but no trees. Wonder if he should have tried to put it down on the landfill straight ahead instead of turning into a tree-lined street.
This is my dream affordable aeroplane. Terribly sad loss.
Very unfortunate. RIP. Good analysis, Juan.
There are thousands of Diamond DA40s and DA42s flying happily with Austro engines which are converted Mercedes diesels.
They have a real company backing them that’s spent thousands of hours on R&D to get them to work properly. Rotax and the Austro motors aren’t even remotely comparable to the applications on 99% of auto conversion homebuilts.
Consider that diesels operate at lower RPM than gas burners
@@DanielJohnson-ec8rk 4000 - 5000 rpm is still too much for the direct drive of the prop. DA40 has roughly 2:1 gear ratio.
@@PecekMichal that’s why I said diesels run at lower RPM, generally not more than 2,000
@@DanielJohnson-ec8rk please show me one diesel engine in an airplane running at 2000rpm. The few I know of are running at around 4000rpm
Sounds like he almost made it down. Every time I hear about the loss of an experienced pilot, it makes me think about what I could do to avoid a similar fate. Thats why this channel is so valuable.
Thank you, Juan.
Outstanding analysis as always, Juan.
More than likely the prop failure occurred first then the engine overrevved.
yup
👍🏻👍🏻👍🏻👍🏻
NTSB are no dummies, and they have video?
That’s a tough one. I worked at Titan for a few years and knew John well. It was difficult to hear of his passing.
This sucks, I spent a long time talking to John at Sun n Fun in 2024 about the Titan 51. He will be sorely missed. RIP sir.
@blancolirio I myself have an LS3 powered T51, nothing wrong with the automotive conversion. After Johns accident I believe I found what may have caused the catastrophic result which I’m now open to sharing. The Link ECU used has certain parameter settings, one being the Engine RPM limit. After thorough investigation, the ECU had the ENG RPM parameter set to 4500 however, it was not turned on. The design fault here has the throttle linkage set to WOT, essentially allowing the engine to go to 6600rpm. Put two and two together, throttle linkage break lead to full WOT, no ECU protection, governor failed to govern due to a high rpm acceleration exceeding the rate at which the governor could manage the load. This in turn caused the prop to swing at 3500rpm. Centrifugal load tore the hub apart. I contacted all Link ECU owners of the T51 LS3 and all found the same issue (ECU parameters set but not turned on). A simple fix but a tragic loss to find the reason behind the cause of the accident.
Sad that the pilot was not able to land successfully. He was careful not to take the passenger until he tested the plane.
My only question I may have missed if you mentioned it was.....was the prop the type with a variable pitch...a loss of pitch control would be the only way it could have over revved before the loss of the blades...
May God comfort his family. My sincerest condolences.
RPM could not surge so rapidly without loosing the load on the engine . So possibly the connection was broken inside the hub which caused the detachment of the blades simultaneously causing the over revving heard by witnesses. The oil spray on the underside of the aircraft could have been from detonating the LS engine .
Prop first or engine first?
Read the report.
“When the airplane pitched up, he heard the engine go to a “super high RPM” and then the “entire prop hub shatters.” He observed several parts and pieces explode from the nose section of the airplane, and the engine noise subsequently went silent.”
This one was close to home. Condolences to friends and family.
My educated guess is either a loss of oil pressure of the prop regulator failed, causing it to rapidly adjust to fine pitch
The delay in sound transmission is a more likely explination for the over-speed so basically after the hub had failed.
I wonder if he clipped the tree because he turned slightly to the left to avoid the oncoming car. The driver of the car reported seeing him coming head on and pulling off the road to his left. They each went left to avoid a collision.
I was wondering that too. I feel bad for the driver in that case. Wrong place wrong time.
sorry for the lost of an experienced EAA pilot.
perhaps the engine didn't need the added oil? Would like more info on the LS3's condition (I'm a Vette owner, it's a great engine)
I also don't understand why he opted for a residential street with trees ... rather than the runway right behind him with apparently plenty of energy.
Nice Coverage Juan. Thank you.
Fuel injected engines like the GM LS engine are computer controlled that have adjustable Rev limiting features. There’s no way the engine could over speed the set limit under any circumstances, especially in this case while under load. The engine hit the set limit RPM only after the load (the gearbox and propeller) was was suddenly disconnected. What was seen and heard was the failure of the gearbox or prop hub failing that caused the engine to rev to the set limit and the pilot then pulling off the throttle.
As a caveat with my statement is that I don’t know what ECU is used in this application. If not a GM supplied unit, pretty much all aftermarket controllers offer the same functionality as GM units in automotive applications. Meaning RPM control would be the same.
Additionally, many aftermarket ECU’s or PCM’s offer (as do most GM units) transmission input and output shaft speed sensors that can sense slippage. Some also offer driveshaft speed sensors, all of which could easily be adapted to gearbox and propeller speed monitoring that will instantly reduce engine power output or cut power to the ignition coils when shaft speeds exceed parameters.
I'm curious about the reported oil spray. I wonder if they will be able to separate the oil that certainly sprayed out during/after the crash from any that might have been in-flight and part of a loss of oil pressure to the hub.
I think the comments about loss of oil pressure leading to a prop feather are onto something. But perhaps there was a mechanical malfunction (leak) that contributed to the loss of pressure. If the thing was already "low on oil", was it due to oil consumption or was it possibly losing some oil under pressure from somewhere?
I'm not sure what the oil consumption norms are for the LS engine.
Would be interesting to hear about if they do a teardown of the engine. Perhaps debris in the oil pickup tube?
Certainly this has been addressed, but in an LS, I wonder where is the oil pickup tube in relation to the sump, especially when doing a high-G pitch up maneuver.
Also, not sure which generation of LS engine was used, but I know from following some hot-rodder youtube channels that there is an aftermarket oil tube pickup brace guys like to add to strengthen the attachment, as from the factory there is only one bolt holding it into the pump instead of two. Perhaps things like this were a failure point during a high-G maneuver which was overlooked as the engine was never designed for this type of application.
I admire doing these kind of engine swaps. Takes some serious engineering.
But certainly there are all kinds of issues like this that would be hard to track down without encountering an unfortunate failure.
Should have gone for the field and left gear up .terrible sorry this happened.engine revved due to loss of weight.of prop RIPJohn
My feeling is the urge to save the airplane was overwhelming, witness the turnback and lowering the gear. I agree, straight ahead into a field was doable, he had the advantage of no drag from a windmilling 4 blade prop, and a bunch of altitude to work with. Very sad. Similar outcome to the Howard Hughes racer replica accident a few years ago, prop governor failure and instead of using the chute, pilot tried to save the airplane by landing into rough terrain.
RIP . condolences to family & friends. what’s the procedure for a lost prop governor , while airborne ? 1. throttle to idle 2 . climb to slow down windmilling prop 3. ??? deadstick .
i’m just guessing. only heard of situations like this from fellow aviators…
I can certainly understand the attraction of flying, but as a non-pilot observer reading the almost daily barrage of ghastly fatal GA incidents that include the most proficient and experienced pilots within your community.... bless y'all, you have much bigger balls than I do.
Far more auto fatalities every day. Yet you'll hop right in one and drive away.
@@barrygrant2907 Two things for sure, I will never be killed by a shark, and I will never be killed in a GA crash.
Very sad indeed.
Thanks again Juan.
That road would not have been my first choice for a forced landing. Looking at the surrounding area there was a field directly in front of him, with a couple more to the east.
I looked at those too, maybe not a wheels down landing, but they seem good enough for a belly landing.
Yep - not sure why Juan didn't reinforce that. It's a reoccurring issue
He might have been too high at that point, but the landfill further North also looks like a possibility. No trees at least.
This time of year, the field is probably full of corn. It might have been safer than a narrow tree-lined road, but it might not have seemed safer in the split-second needed to make the decision.
@@StrongDreamsWaitHere I guess, I'd rather corn than a small road though. It's the insurance's plane the moment it breaks, not mine.
Where did they get the LS info? A LS3 is 415 HP not 300