@@ZuminaZX wow i hadnt heard that would be well worth careful consideration obviously auto vs aero is a whole different dynamic but im sure Peter has/is weighing alternate srategies often.
Ya, true but when a powertrain engineer spells out the exact reason this system is both down on power and generating excessive heat you need to listen.
So when you have oil starvation and engine failure like this it's a good chance you sent bearing/journal material through the entire oiling system. Make sure you replace any heat exchangers that have oil running through them and clean all the lines that carry oil in them. Debris will stick and hide there and then ruin your new engine when you go to start it. Just spraying brake clean through lines isn't good enough either, please keep all this in mind. Also as someone mentioned it would be a good idea to redo your turbo setup. I would go with a turbo with a larger exhaust side (wheel and housing), as response and boost threshold is not an issue here. This will net you lower exhaust backpressure, increase engine volumetric efficiency, and make life easier on the engine and exh. components.
@@jekader no, you'll have debris all in your system. The filter is usually located right as it feeds the block but all your debris and carnage are happening in the block and getting sent downstream. Trust me I've seen plenty of people mess up their new engine builds in a car because they forgot to flush the oil cooler and it had bearing/journal material in it. Also automotive filter housing have a bypass valve, after a certain oil pressure they bypass the filter and you're running unfiltered oil through the system. Would actually be very good to figure that out on this engine Peter, and see where that bypass opens up at. If it has a bypass then I would do a remote mount large filter (to handle the volume/pressure) and eliminate the bypass.
Since you have to do a new motor.. Take the new engine to a dyno so you can verrifi power and to find that your turbo setup isn't correct and fix it now.
This is the best idea in the comments section. It would definitively show how much actual horsepower is being delivered and either highlight the problems or vindicate the designer...
Keep the spirit up! We all rooting for your success! Take your time and do everything correct. Don’t mind the UA-cam-stalkers, like myself, wanting an update everyday. This time I’ll gladly wait. You survived a flight with a broken engine, and kept plane intact. ❤️
Sorry about the setback Peter but as always great job figuring out the issue and moving forward. I think the whole situation is also a testament to the safety of the aircraft and the resilience of the engine itself. You had a total catastrophic engine loss and still managed to get the plane on the ground safely and with minimal damage. Can't wait to have one of these kits in my shop!
It sucks that the engine is shot but I'm actually really glad that it is. No matter what that engine sustained damage due to the starvation event and I'm afraid if it had started back up you would have just gone out and started flying again. On another note I'm wondering if the oil seal blew out in the turbo which then blew out the seal in the redrive. Chances are the engine dying in the air was due to it catastrophically failing internally. There was a hell of a vibration before it actually shut off.
I know it’s down the road, but it will be nice when the electric jobs and the batteries to support them are up to par for these types of air craft . A lot less moving parts , more power and quieter plus cheaper to fly .
The most likely sequence is the piston seized and the spike in RPM you saw was the rod breaking allowing the engine to spin faster before it shutdown. The second turbo should be closely examined internally and re-built as well, because turbos spinning at 10's of thousands of RPM handle loss of oil even worse than engines. The entire oiling system needs to be flushed and cleaned. Every line and cooler needs a flush and if possible borescope inspection. There's a high probability that metal particles were flowing around the system. You do not want to install a replacement engine and have it destroyed by FOD inside the oil system. Now would also be a good time to re-design the cooling system and intercooler layout to make it more reliable and effective. Why not since you have to restart the 40 hour fly-off on the power train?
I’m happy you lived through this incident. Now would be a very good time to find out whether the wing structure has damage and start planning a flight testing program that immediately focuses on the flying qualities of the aircraft and not the electronic gadgets. From what I can see, there are a lot of unanswered questions on slow flight handling, glide speed, steep turns, etc. If you don’t know these qualities you may not be so lucky next time.
Two weeks and $5000 for a replacement (used) engine is one great selling point going forward and a hell of a bargain for a major engine failure. Also, thank you for remaining cool and disciplined with regard to keeping your viewers( future customers?) current each step of the way.
Call me a nervous Nellie, but the way that keeper ring is being pushed out by the seal; me thinks 3 three tabs around the ring to hold it in place AND act at a 2nd seal retainer, would be a good idea. Plenty of meat on the surface to drill and tap for some bolts to hold snap ring keepers. Considering the huge cascade failures when that seal blows it would be very cheap insurance.
Keeper ring wasn’t pushed out by the seal, mate. Peter omitted to install it when he changed the seal a short while ago, hence the unretained seal pushed out under pressure - it had no retention fixture present.
This is your chance to upgrade to the same engine but the biturbo version which has stock 326 hp and wider cooling channels and better bearings. It has been tuned to 460 hp without problems.
Peter thank God you are safe. Like you said it is what it is but bottom line this is exactly why experimental airplanes must fly the 40 hrs. Keep plugging away sir,.
The plus side of having an Audi engine. The IO 540 I built for my velocity was over 50k. You’ll get’er done and the plane will be even better. You got this Peter, cheers!
I think you recieved a gift from the Gods. On the grounds safely, no air frame or gear damage. Great time to update all the documents; procedures, engine build, plumbing, part numbers, design updates. Take your time. You and your teams are on the way!
I was in the training area with my instructor when we had a noise coming from under the cowl so he assessed our Alt. and Dist. to the airfield and shut the engine off. We glided back to the field and restarted it (at a point where options were available) to fly a close in circuit and land. A through bolt holding the case halves together had broken and his actions saved the engine and also gave us power when we needed it.
Might also look into ensuring certain lubrication aspects are looked into further and still needing to be altered for use in an aviation application. Automotive engines typically don't see much change in orientation except for fairly brief moments. Even if you set it up with an dry sump, there could be things in the heads with how it drains, etc. You could be trusting a passage to stay pressurized but changing the angle could have it sucking in air somewhere internally and not getting oil to all parts, etc. So might be worth looking into with the tear down if it was particularly oil-starved anywhere.
@@leoa4c Hi Leo, When Peter has done his postmortem he will be able to tell us what happened. Until then, my best guess is that the loss of oil pressure resulted in damage to the rod bearing. This typically results in very large clearances between rod end and crank and pounding that breaks a rod bolt.
Hand spinning the old turbo sounds a bit "sandy" so there may be a bit more internal damage than just the seal blowing. Just as well you caught it and have swapped the core for a nice shiny new one. That con-rod bearing/wrist pin failing is not a good thing - all the best on getting it all back together. My guess at sequence of events is - oil loss, pin fail, turbo blow, engine shuts off on vibration & low oil. The last steps being almost at the same time.
pete one to look out for regarding the turbos. im not 100% sure about the Audi/VW group diesel engines but the japanese stuff like mitsubishi and izuzu , the turbo centres and bells are machine matched and to use anything else can lead to compressor blade fouling or poor sealing surfaces which leads to a very high pitched hiss boost leak. just a thought pal.
Could the turbo seal have failed first and pressurized the oil return line which pressurized the Re-drive oil return line which pushed the seal out which resulted in the oil loss?
I was wondering the same thing. Peter mentioned a few weeks ago he changed the re-drive seal because it was weeping. Wondering if the turbo seal was the trigger all along? However, it’s also possible the oil-starved turbo blew it’s seal only due to the lack of lubrication too. It’s one of these “chicken-and-egg” things we will probably never definitively know the sequence of events on. However, with the retaining ring now back in the re-drive, this type of failure shouldn’t happen (as long as the retaining ring stays put 👍🏻).
Thanks Peter, bit disappointing as you say. However, you got her back on the ground, which you (and we) should be grateful for, and you have a plan to swap out the engine. Problems will always happen on prototypes - it's the name of the game unfortunately. Best to find out now in pre-production and introduce a fail-safe wherever possible. Keep pushing on. Cheers.
I recognize the cost with the engine, but might be a good time to go with a conventional engine while you work on the airframe; then work on the engine. Working on new airframe and new engine at same time is a lot of work, with sooooo many variables.
Yes, a classic road to trouble, new airframe AND new engine, but here the new engine is so crucial to the concept, while the airframe is relatively conventional and seems to have so far had few problems, which were mostly solved early on (e.g. the nosewheel shimmy). Flight characteristics, while far from full explored, seem benign. Nearly all the difficulties seem to be engine related (e.g. cooling) and are related to its adaptation (as in this unfortunate engine RUD). Perhaps an engine guru should look over everything while it is disassembled or being put together, to help pick up the gotchas.
Sorry Peter to hear the engine took a dump on that last flight. The turbos I expected but the engine I didn’t. Great job on owning one’s mistakes and we will be here rooting for your success all the way. Cheers Peter! Good luck.
It's really not a surprise. The engine ran with little to no oil for several minutes and internal damage is almost inevitable in that case.it's really a good thing that it threw a rod because otherwise he might have just gone flying again which would have been a mistake.
@Do RC -it would have required a complete tear down and evaluation and who knows what he could expect after overhauling the same engine. I didn’t know how low the engine oil was compared to what the turbos received. But now we know.
@@MrWATCHthisWAY It seems that the initial loss of oil pressure when the re-drive popped its seal was the first of a number of dominoes to fall. Too many critical systems relying on one engine-driven oil pump and supply. Loss of pressure anywhere in that chain and you loose everything. Would it be practical for the Re-drive to have its own independent pump and sump?
This might be a blessing in disguise. You have totalled most of the firefall forward. This is a good opportunity to re-assess and redo choices. Now is the time to make sure you are happy with turbocharger choices, intake and exhaust plumbing, maybe even radiator choices.
The light shadows on the snap ring holding the new seal in the reed drive look like it is slightly twisted, like a Belleville spring. That is not preferred. Please be careful.
A very close call,that motor ran just long enough to save you and the airframe. I spun a bering in my car just cruising on the freeway, it took about 5 seconds and it was over. Glad your getting a new engine. Keep us posted. Now is the time to design a new cooling system and fix your turbo system.
I know this old now but is it possible the first fail was the turbo seal? It would have passed exhaust into the oil and possibly pressurized the engine internally causing that seal to pop out. The reason I suggest this is I once had a small diesel engine that was popping the crankshaft seal. Turned out to be caused by a wasp having built a nest in the crankcase breather.
I was thinking the same... could have saved the work of putting the redrive, prop, and turbo back together....my mechanic cuts the filter open on EVERY oil change.
Please tear down your re-drive and make sure the transfer sleeve didn’t touch the prop shaft. Replace bearings too. Cheap and piece of mind. Be worth replacing your belts and looking at the dyno coupling.
Thank for the update. I knew you will get to the bottom of what went wrong and failed. I am always looking forward to al your updates and I do wish you the best of success.
Sorry the engine got junked, but glad you found it before taking her airborne. Good idea to get two engines, so you have a quick change option. Obviously cost is consideration.
Well the good news here is that your now have a second engine on hand as I assume you will be repairing this one once it is pulled out if possible. If it can't be pushed back in to service, At least you will have parts.
The good outcome - if it was conventional airplane engine replacement would cost you ten time more. Two weeks to get a new engine and build it up? That is out of reality.
the Bad news engine failed the good news only $6500 for replacement i would be shaking in my boots if it was a twin snail 0-550. I believe you have a winning combination and are paving a way into the aviation history books, and youyr nearly there your doing an exceptional job mate.
Run one with no oil pressure and I’m sure it will run metal rich just as well. Hope Peter gets the Audi working well because huge benefit to ga sector as well as may force lycoming and continental to innovate a little more as well as competition means we all win.
Peter, sorry for the engine/turbo set back, very glad to see you almost sorted and moving forward, best wishes. I remain curious about the “chicken & the egg”aspect of the turbo & engine failure. I believe there is still merit in having a lab do an oil analysis, of the failed engine & the failed turbo, if the turbo and engine do not share the same oil system. Respectfully, a lot can be learned, with a 3-4 ounce sample of the oil that was in the Raptor’s oil system(s) during the last test flight. I have performed or been part of engineering groups that have analyzed several hundred powertrain failures for various aviation, marine & automotive folks. We try to start any failure analysis with a lab analysis of the fluids.
Since you have the time why not take the re-drive apart and have the seal bore deepened to allow for variance in seal thickness and easy installation of your seal retainer.
Just saw this video was shocked anyhow I’m glad both man and machine got safely on the ground. Peter perhaps you should look into hybrid power plant with backup electric motor for engine failure cases!
A fine opportunity to clean up the exhaust manifolds flow by removing to protrusions of the exhaust pipe that extend into the flow. Simply burr them into shape. Good luck and cheers.
I've only been half following this saga, so please forgive me if my observation is flawed. Peter seems to think the low oil condition caused the turbo seal to fail, but what are the chances it was the other way around? If the turbo seal failed and allowed full pressure to flow through the oil loop it could have easily blown out the redrive seal which had never showed sign of movement in the previous 100 hours of running. If UnevenHeathen's comment about the turbos being incorrectly setup is correct, it stands to reason that the turbo failure may have been a cause and not a symptom as initially supposed.
Not flawed at all. Also oil pressure does not keep the failed seal in place! It looks like it may be the seal for the thrust bearing housing and freely draining chamber which is at crankcase pressure.
Won’t you have to begin over again with the 40hr test phase? Swapping out an engine is obviously considered a major airframe change requiring a new phase 1 test period.
I was never clear on your prop design capability. And you mentioned several times that the flat drag was sufficient such that spoilers were unnecessary. Considering your recent experience. would a Full Feathering Prop have given you the margins to save the airframe had things not "gone so well"? It's a rhetorical question I propose for your thought on design improvements in the future. Glad you're OK. www.mt-propellerusa.com/en/mtusa/products.htm
A good point. As I understand, his 5 blade prop went to to flat pitch on power loss, not a good failure mode. An automatic feathering (MT) electric prop would be a simpler solution and safer. The high power off decent rate shown on final illustrates the poor glide ratio.
Well thats a lot cheaper then a contenental or Lycoming! Turbos alone are 30 grand! I really hope you can succeed with a auto engine! Technology on them has come such a long way compared to certified engines and they are fractions of the price! Keep up the good work!
@@thomasaltruda So why do you imagine that Continental Aerospace Technologies have taken a stock factory Mercedes-Benz 3.0 litre V6 diesel and converted it into their newest certified aircraft engine, the CD-300, which is technically very similar to the Audi/Porsche/VW 3.0 litre V6 diesel in the Raptor. The answer is that TCM, as they then were, have been manufacturing the CD-135 and CD-155, now developed into the CD-170, for about a decade and they have turned out to have about the same number of in flight shut downs as turboprops. www.continental.aero/diesel/engines/cd300.aspx
With the amount of oil pouring out and the engine completely shutting down, I thought the odds were going to be high that that would be the result. it's a setback, but you will get past it. It could have been much worse.
That looks like a nice engine, and unfortunately also a very expensive one. The thing with the Raptor was to use an inexpensive engine that could be easily found and purchased.
As far as I can get the project philosophy itself was to use an engine from automotive. The reason it's because it's easier to find, cheaper, and it's not so complicated to do maintenance and to adapt to different gauges manifolds for both intake and exhaust and a FADEC ECU suitable for an airplane. The VW TD V6 engine it's one of the most common available V6 around in the US alongside some Ford and Dodge quite similar models.
@@hansroemerszoonvanderbrikk7626 What is the reliability of an automobile engine in aviation? I think the VW TD V6 engine will not be able to work for a long time under load. Has life restarted? Is the Continental CD-300 Jet-A expensive too? Peter good luck!
@@mauricewalter4739 Usually a diesel engine it's quite reliable, what makes it less reliable it's typically the turbo setup, the intercooler, and continuous accelerations and pressure stress. The stress on a plane it's not made by fast accelerations but by the duty itself. If you stay within the designed power parameters you can obtain a lot of duty hours, usually many more than a petrol engine. Consider that a diesel car could achieve half a million KM without major issues, a petrol engine is going to suffer at half that mileage. Also, the over head camshafts are no longer as fragile as the first ones, the ones with chains proven to be even more reliable than the plain old rod and over head balancers due to a very precise valve timing, and they also allow to offset the timing to achieve variable combustion ratios. If you create a proper map on the FADEC ECU and you correctly cool the turbo the overall reliability should be higher than a petrol aircraft engine.
All part of the failure cascade: Loss of oil pressure = spin the bearing = rod bottom end starts pounding = breaks a rod bolt = if you are lucky, rod and piston stay at the top of the compression stroke and let the engine continue to turn.
Very glad to hear that a new engine will be going in. Given what you know now about the thermostat etc etc, would this be an opportunity to simplify the cooling system somewhat? Seems to me that quite a lot of complexity and weight has been added during recent work, and some of it may not now be necessary. Simpler is better.
I realize you had much more important things going on, but did you not hear that rod, or maybe even on the recordings . Also how much is a prop that feathers ? Btw, l still luv the combo of sound of that Diesel and prop . Also the concept and implementation thereof .
Hi peter, good job in isolating the problems. I'm curious to know how you fixed the fin on the bottom of the wing that scraped the runway when you came in for the emergency landing.
Great idea it’s never good when you starve an engine from oil or you think it might have been a new motor will be good give you a lot more information and you’ve learned a lot from the first situation so when you go into production you will know where to watch the issues are it’s just part of this game
Wow, great great great video! 100% awesome Peter. You get a POB Pat On the BACK! You Peter are a force for good. You are providing education that is second to NONE!! Beers on me.
Use a decent turbo charger lot of good manufactures out there. Don't use crappy Chinese turbo chargers like Sonex does on their VW aerovee. I love how you went with a modern diesel engine just ignore all these people who keep saying use a 70 year old aircraft engine.
Since you had to remove it and you bought an entirely new turbo anyways, it probably would have been a good idea to size them appropriately in the meantime. There are a lot of very knowledgeable people trying to help you and it appears you just love beating this horse.
I just had to rebuild a $5,000 motor with 100 miles on it for a similar little problem that cascaded into a spun bearing as well. I am so sorry you experienced the same kind of thing. Adapt and overcome, you got this and I'm sure it'll be better than ever before.
Wow so sorry Peter. :-( If you're going to swap out the engine, would you please consider checking the other turbo (center section as well?) Perhaps it's alright, however with that level of damage, I think its prudent to pursue that level of detailed inspection. The last thing you need on the next flight is for a turbo to spit any debris (large or fine) into the intercooler of unknown size and possibly have it make it's way into the combustion chambers. All the best, Mo-
That engine runs much faster (higher revs) in Diesel race-car applications, methinks. I am always surprised at how fast they run them as Diesel race-car engines.
@@SomeGuyInSandy . Agreed. On another topic I here a lot of commentary from People obviously familiar with Fords, Chevs, Gasoline auto engines, etc. who, I suspect, have no experience of European Diesel Auto engines (in terms of sleeves & re-buildability) durability, etc., and who would be well advised to WAIT & SEE before playing "Mr. Instant Expert" (NOT referring to you here !!). Lots of Wise Guys who have NOTHING invested in the exercise. and one feels, little real experience, but rich in instant opinions.
@@SnowAndrews I hear you there too! The idea of a diesel aero engine has a lot of pluses. High torque, low(er) RPM, cheaper fuel... I think it's a great idea.
I feel your pain, Peter. My beloved Subaru Outback was totaled this week (the other driver’s fault), and I too spent Valentine’s Day alone, working on engineering projects.
I really feel you should look for some causes of why you’re having failures on this relatively new engine. I believe you need to address the overheating problem. Heat stress can cause turbo failure, oil leaks, seal failure which all can be compromised by overheated oil and higher pressure. Would it be a bad idea to have someone consult you on ducting air appropriately through this engine bay to keep it well under the heat limits instead of operating at the top of the temperature limits.
@@stevenhorne5089 He was given the reason for the high heat by an Audi engineer, which is poor twin turbo design & setup. He mitigated it by detuning the boost and adding a bunch of cooling. He didn't fix the root cause of the overheat tho.
@@johngoscinski1995 Hey John. Checking the Audi TDI diesel recommendations with turbos, the ideal operating temperatures are 102 Celsius to 110 Celsius. This is 210 to 230°F. I really love what raptor is trying to do but it seems they’re modifying their flight testing to keep the oil temperature below 240. I’m concerned someone flying the plane within normal climb maneuvering rates on takeoff at what most other aircraft will do in this category will be pushing the oil temps over those temp limits for longer periods of time. I think it is a fundamental cooling problem that should be easy to address by modifying the way the engine compartment and additional oil cooling radiators are operating at all times. When operating this engine on the ground during the summer, it would not operate under 240°. That’s an issue. What if stuck on an airstrip in line for an hour on a hot day then has to take off and climb out rapidly? My belief is he needs to rebuild the engine cooling set up from the ground up for all flight and taxi situations. This will probably need the addition of fans as well as a better design method of moving air efficiently through the aircraft and the engine compartment. My guess is bigger radiators, better ducting and the addition of fans for taxi in hot weather. If you start out on the ground at the upper limits the plane is being stressed during climb. . Better have the plane leaving the ground well within limits. Building a cooling system now will be a hell of a lot cheaper and safer than buying new engines after they fail.
Where is your new engine coming from? I thought the 3.0 TDI was recalled in the US (Dieselgate) and VW/Audi isn’t going to sell TDIs in the US anymore, having committed instead to electric powertrain development. Doesn’t that make availability of replacement engines a problem in the future?
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This would be a good time to really consider what the audi engineer told you about the turbo setup
What did the Audi engineer say about the turbo setup?
He said the turbos are backwards and that he's losing a lot of power and creating a lot of strain on the system which produces excess heat.
@@ZuminaZX wow i hadnt heard that would be well worth careful consideration obviously auto vs aero is a whole different dynamic but im sure Peter has/is weighing alternate srategies often.
Ya, true but when a powertrain engineer spells out the exact reason this system is both down on power and generating excessive heat you need to listen.
@@ZuminaZX He did have an issue with an improperly wired thermostat. I don't know if that explains the low power though.
So when you have oil starvation and engine failure like this it's a good chance you sent bearing/journal material through the entire oiling system. Make sure you replace any heat exchangers that have oil running through them and clean all the lines that carry oil in them. Debris will stick and hide there and then ruin your new engine when you go to start it. Just spraying brake clean through lines isn't good enough either, please keep all this in mind. Also as someone mentioned it would be a good idea to redo your turbo setup. I would go with a turbo with a larger exhaust side (wheel and housing), as response and boost threshold is not an issue here. This will net you lower exhaust backpressure, increase engine volumetric efficiency, and make life easier on the engine and exh. components.
Good point about debris in the oiling system, but isn't the oil filter going to handle that?
@@jekader no, you'll have debris all in your system. The filter is usually located right as it feeds the block but all your debris and carnage are happening in the block and getting sent downstream. Trust me I've seen plenty of people mess up their new engine builds in a car because they forgot to flush the oil cooler and it had bearing/journal material in it. Also automotive filter housing have a bypass valve, after a certain oil pressure they bypass the filter and you're running unfiltered oil through the system. Would actually be very good to figure that out on this engine Peter, and see where that bypass opens up at. If it has a bypass then I would do a remote mount large filter (to handle the volume/pressure) and eliminate the bypass.
Since you have to do a new motor.. Take the new engine to a dyno so you can verrifi power and to find that your turbo setup isn't correct and fix it now.
This is the best idea in the comments section. It would definitively show how much actual horsepower is being delivered and either highlight the problems or vindicate the designer...
Good idea. Too bad he won't entertain it.
Show a teardown of the engine while you are waiting!
Keep the spirit up! We all rooting for your success!
Take your time and do everything correct. Don’t mind the UA-cam-stalkers, like myself, wanting an update everyday. This time I’ll gladly wait. You survived a flight with a broken engine, and kept plane intact. ❤️
Sorry about the setback Peter but as always great job figuring out the issue and moving forward. I think the whole situation is also a testament to the safety of the aircraft and the resilience of the engine itself. You had a total catastrophic engine loss and still managed to get the plane on the ground safely and with minimal damage. Can't wait to have one of these kits in my shop!
It sucks that the engine is shot but I'm actually really glad that it is. No matter what that engine sustained damage due to the starvation event and I'm afraid if it had started back up you would have just gone out and started flying again.
On another note I'm wondering if the oil seal blew out in the turbo which then blew out the seal in the redrive. Chances are the engine dying in the air was due to it catastrophically failing internally. There was a hell of a vibration before it actually shut off.
Maybe need a larger or dedicated drain back. Better venting.
Keep moving forwards mate. Mistakes happen, its how we recover that determines who we are.
I know it’s down the road, but it will be nice when the electric jobs and the batteries to support them are up to par for these types of air craft . A lot less moving parts , more power and quieter plus cheaper to fly .
The most likely sequence is the piston seized and the spike in RPM you saw was the rod breaking allowing the engine to spin faster before it shutdown. The second turbo should be closely examined internally and re-built as well, because turbos spinning at 10's of thousands of RPM handle loss of oil even worse than engines. The entire oiling system needs to be flushed and cleaned. Every line and cooler needs a flush and if possible borescope inspection. There's a high probability that metal particles were flowing around the system. You do not want to install a replacement engine and have it destroyed by FOD inside the oil system.
Now would also be a good time to re-design the cooling system and intercooler layout to make it more reliable and effective. Why not since you have to restart the 40 hour fly-off on the power train?
I’m happy you lived through this incident. Now would be a very good time to find out whether the wing structure has damage and start planning a flight testing program that immediately focuses on the flying qualities of the aircraft and not the electronic gadgets. From what I can see, there are a lot of unanswered questions on slow flight handling, glide speed, steep turns, etc. If you don’t know these qualities you may not be so lucky next time.
Two weeks and $5000 for a replacement (used) engine is one great selling point going forward and a hell of a bargain for a major engine failure. Also, thank you for remaining cool and disciplined with regard to keeping your viewers( future customers?) current each step of the way.
Innovation is never easy or cheap. But the replacement cost is so low compared to what an aviation motor would cost. Love the disruption!
Call me a nervous Nellie, but the way that keeper ring is being pushed out by the seal; me thinks 3 three tabs around the ring to hold it in place AND act at a 2nd seal retainer, would be a good idea. Plenty of meat on the surface to drill and tap for some bolts to hold snap ring keepers. Considering the huge cascade failures when that seal blows it would be very cheap insurance.
Keeper ring wasn’t pushed out by the seal, mate. Peter omitted to install it when he changed the seal a short while ago, hence the unretained seal pushed out under pressure - it had no retention fixture present.
I'm addressing the current situation, not the previous one.
This is your chance to upgrade to the same engine but the biturbo version which has stock 326 hp and wider cooling channels and better bearings. It has been tuned to 460 hp without problems.
Peter thank God you are safe. Like you said it is what it is but bottom line this is exactly why experimental airplanes must fly the 40 hrs. Keep plugging away sir,.
The plus side of having an Audi engine. The IO 540 I built for my velocity was over 50k.
You’ll get’er done and the plane will be even better.
You got this Peter, cheers!
I think you recieved a gift from the Gods.
On the grounds safely, no air frame or gear damage.
Great time to update all the documents; procedures, engine build, plumbing, part numbers, design updates.
Take your time.
You and your teams are on the way!
@@blowinkk9396 I'm hopeful.
No marks on the flying services, that I could see.
Should be a 'g' meter or two on board, equaling some data.
I was in the training area with my instructor when we had a noise coming from under the cowl so he assessed our Alt. and Dist. to the airfield and shut the engine off. We glided back to the field and restarted it (at a point where options were available) to fly a close in circuit and land. A through bolt holding the case halves together had broken and his actions saved the engine and also gave us power when we needed it.
Might also look into ensuring certain lubrication aspects are looked into further and still needing to be altered for use in an aviation application. Automotive engines typically don't see much change in orientation except for fairly brief moments. Even if you set it up with an dry sump, there could be things in the heads with how it drains, etc. You could be trusting a passage to stay pressurized but changing the angle could have it sucking in air somewhere internally and not getting oil to all parts, etc. So might be worth looking into with the tear down if it was particularly oil-starved anywhere.
The only real mistake is the one from which we learn nothing,-- Henry Ford
Now you have a spare engine to salvage parts from, nice!
Having a 'spare' engine could be handy for prototyping new innovations that will just bolt right on to the engine you are flying with.
Another cup half full guy huh. Good way to be
@@leoa4c Hi Leo, When Peter has done his postmortem he will be able to tell us what happened. Until then, my best guess is that the loss of oil pressure resulted in damage to the rod bearing. This typically results in very large clearances between rod end and crank and pounding that breaks a rod bolt.
Hand spinning the old turbo sounds a bit "sandy" so there may be a bit more internal damage than just the seal blowing. Just as well you caught it and have swapped the core for a nice shiny new one.
That con-rod bearing/wrist pin failing is not a good thing - all the best on getting it all back together.
My guess at sequence of events is - oil loss, pin fail, turbo blow, engine shuts off on vibration & low oil. The last steps being almost at the same time.
pete one to look out for regarding the turbos. im not 100% sure about the Audi/VW group diesel engines but the japanese stuff like mitsubishi and izuzu , the turbo centres and bells are machine matched and to use anything else can lead to compressor blade fouling or poor sealing surfaces which leads to a very high pitched hiss boost leak. just a thought pal.
its really common in car tuning to swap out cores these days as well as end to make up the power you need
A couple of steps backwards, but you’ll get it all ironed out!!
Could the turbo seal have failed first and pressurized the oil return line which pressurized the Re-drive oil return line which pushed the seal out which resulted in the oil loss?
I was wondering the same thing. Peter mentioned a few weeks ago he changed the re-drive seal because it was weeping. Wondering if the turbo seal was the trigger all along? However, it’s also possible the oil-starved turbo blew it’s seal only due to the lack of lubrication too. It’s one of these “chicken-and-egg” things we will probably never definitively know the sequence of events on. However, with the retaining ring now back in the re-drive, this type of failure shouldn’t happen (as long as the retaining ring stays put 👍🏻).
Thanks Peter, bit disappointing as you say. However, you got her back on the ground, which you (and we) should be grateful for, and you have a plan to swap out the engine. Problems will always happen on prototypes - it's the name of the game unfortunately. Best to find out now in pre-production and introduce a fail-safe wherever possible. Keep pushing on. Cheers.
Well you got down safe and that’s the important bit. Some money and time and you are up in the sky again!
Keep the great attitude Peter! Minor setback. Could have been a lot worse.
I recognize the cost with the engine, but might be a good time to go with a conventional engine while you work on the airframe; then work on the engine. Working on new airframe and new engine at same time is a lot of work, with sooooo many variables.
Yes, a classic road to trouble, new airframe AND new engine, but here the new engine is so crucial to the concept, while the airframe is relatively conventional and seems to have so far had few problems, which were mostly solved early on (e.g. the nosewheel shimmy). Flight characteristics, while far from full explored, seem benign. Nearly all the difficulties seem to be engine related (e.g. cooling) and are related to its adaptation (as in this unfortunate engine RUD). Perhaps an engine guru should look over everything while it is disassembled or being put together, to help pick up the gotchas.
@@awuma I said it before I like auto conversions, but I wouldn’t trust this engine in a car, we’ve seen too many issues with them....
Sorry Peter to hear the engine took a dump on that last flight. The turbos I expected but the engine I didn’t. Great job on owning one’s mistakes and we will be here rooting for your success all the way. Cheers Peter! Good luck.
It's really not a surprise. The engine ran with little to no oil for several minutes and internal damage is almost inevitable in that case.it's really a good thing that it threw a rod because otherwise he might have just gone flying again which would have been a mistake.
@Do RC -it would have required a complete tear down and evaluation and who knows what he could expect after overhauling the same engine. I didn’t know how low the engine oil was compared to what the turbos received. But now we know.
@@MrWATCHthisWAY It seems that the initial loss of oil pressure when the re-drive popped its seal was the first of a number of dominoes to fall. Too many critical systems relying on one engine-driven oil pump and supply. Loss of pressure anywhere in that chain and you loose everything. Would it be practical for the Re-drive to have its own independent pump and sump?
@Peter Drury -prop pump sump system, there would be a weight penalty but it’s one less system relying on one sump.
@@MrWATCHthisWAY Agreed. An additional benefit of this would be cooler and cleaner oil running through the re-drive.
This might be a blessing in disguise. You have totalled most of the firefall forward. This is a good opportunity to re-assess and redo choices. Now is the time to make sure you are happy with turbocharger choices, intake and exhaust plumbing, maybe even radiator choices.
Isn’t it firewall backwards?
Fire extinguisher in the engine bay and protective breathing equipment and smoke hood would be on my wish list.
Ejection seat.
@@randallsemrau7845 Already has parachute.
The light shadows on the snap ring holding the new seal in the reed drive look like it is slightly twisted, like a Belleville spring. That is not preferred. Please be careful.
This is why we test! Good work Peter.
Love the positive, can-do attitude Peter! Hope to see some videos of you replacing the engine.
I am sorry to see you having trouble. I have enjoyed your inventiveness and perseverance. Hope to fly a Raptor some day.
God bless you and your great efforts hope you film some of the swap of the new engine!
A very close call,that motor ran just long enough to save you and the airframe.
I spun a bering in my car just cruising on the freeway, it took about 5 seconds and it was over.
Glad your getting a new engine. Keep us posted. Now is the time to design a new cooling system and fix your turbo system.
I know this old now but is it possible the first fail was the turbo seal? It would have passed exhaust into the oil and possibly pressurized the engine internally causing that seal to pop out. The reason I suggest this is I once had a small diesel engine that was popping the crankshaft seal. Turned out to be caused by a wasp having built a nest in the crankcase breather.
Tear filter apart and inspect for any metals.
Why, if I'm replacing the whole engine!
@@RaptorAircraft Perhaps to reinforce the epic Charlie Fox you miraculously avoided?
I was thinking the same... could have saved the work of putting the redrive, prop, and turbo back together....my mechanic cuts the filter open on EVERY oil change.
@@RaptorAircraft .
If/When you can afford the time, there WILL be good learning is seeing where it "WORE" , when it died.
Please tear down your re-drive and make sure the transfer sleeve didn’t touch the prop shaft. Replace bearings too. Cheap and piece of mind. Be worth replacing your belts and looking at the dyno coupling.
Thank for the update. I knew you will get to the bottom of what went wrong and failed. I am always looking forward to al your updates and I do wish you the best of success.
Given the difficulties with that engine, would a Lycoming DEL-120 be more feasible?
Not enough HP. Besides, where's he going to get a military proprietary engine?
Sorry the engine got junked, but glad you found it before taking her airborne. Good idea to get two engines, so you have a quick change option. Obviously cost is consideration.
Well the good news here is that your now have a second engine on hand as I assume you will be repairing this one once it is pulled out if possible. If it can't be pushed back in to service, At least you will have parts.
@@rustyshackleford7022 I hope not, but yeah probably right. Well he'll still get some parts out of it.
The good outcome - if it was conventional airplane engine replacement would cost you ten time more. Two weeks to get a new engine and build it up? That is out of reality.
the Bad news engine failed the good news only $6500 for replacement i would be shaking in my boots if it was a twin snail 0-550. I believe you have a winning combination and are paving a way into the aviation history books, and youyr nearly there your doing an exceptional job mate.
An IO550 probably wouldn't have failed in this state though.
Run one with no oil pressure and I’m sure it will run metal rich just as well. Hope Peter gets the Audi working well because huge benefit to ga sector as well as may force lycoming and continental to innovate a little more as well as competition means we all win.
@@mcatech05 Yes, but the IO550 probably would not be in the situation to make metal in the first place.
Good job Peter! Maybe a nice timelapse of the engine swap... :)
Peter, sorry for the engine/turbo set back, very glad to see you almost sorted and moving forward, best wishes. I remain curious about the “chicken & the egg”aspect of the turbo & engine failure. I believe there is still merit in having a lab do an oil analysis, of the failed engine & the failed turbo, if the turbo and engine do not share the same oil system. Respectfully, a lot can be learned, with a 3-4 ounce sample of the oil that was in the Raptor’s oil system(s) during the last test flight. I have performed or been part of engineering groups that have analyzed several hundred powertrain failures for various aviation, marine & automotive folks. We try to start any failure analysis with a lab analysis of the fluids.
Since you have the time why not take the re-drive apart and have the seal bore deepened to allow for variance in seal thickness and easy installation of your seal retainer.
Just saw this video was shocked anyhow I’m glad both man and machine got safely on the ground. Peter perhaps you should look into hybrid power plant with backup electric motor for engine failure cases!
A fine opportunity to clean up the exhaust manifolds flow by removing to protrusions of the exhaust pipe that extend into the flow. Simply burr them into shape. Good luck and cheers.
I've only been half following this saga, so please forgive me if my observation is flawed. Peter seems to think the low oil condition caused the turbo seal to fail, but what are the chances it was the other way around? If the turbo seal failed and allowed full pressure to flow through the oil loop it could have easily blown out the redrive seal which had never showed sign of movement in the previous 100 hours of running. If UnevenHeathen's comment about the turbos being incorrectly setup is correct, it stands to reason that the turbo failure may have been a cause and not a symptom as initially supposed.
Not flawed at all. Also oil pressure does not keep the failed seal in place! It looks like it may be the seal for the thrust bearing housing and freely draining chamber which is at crankcase pressure.
When are you planning on beginning the flight testing?
Won’t you have to begin over again with the 40hr test phase? Swapping out an engine is obviously considered a major airframe change requiring a new phase 1 test period.
Would like to see a time lapse of how you pull the engine, etc. Most of us like every aspect of the Raptor story!
Interesting. Always more to learn !
With any new endeavor your bound to have setbacks. Learning from them is what will make this project great. Keep up the hard work and press on!
I was never clear on your prop design capability. And you mentioned several times that the flat drag was sufficient such that spoilers were unnecessary. Considering your recent experience. would a Full Feathering Prop have given you the margins to save the airframe had things not "gone so well"? It's a rhetorical question I propose for your thought on design improvements in the future. Glad you're OK. www.mt-propellerusa.com/en/mtusa/products.htm
A good point. As I understand, his 5 blade prop went to to flat pitch on power loss, not a good failure mode. An automatic feathering (MT) electric prop would be a simpler solution and safer. The high power off decent rate shown on final illustrates the poor glide ratio.
Nice to find you in good spirit despite facing adversity yet again. Good luck with engine change Peter.
Bummer. But much better than a (crash)landing in a field! Keep it up man! Thanks for sharing.
Well thats a lot cheaper then a contenental or Lycoming! Turbos alone are 30 grand! I really hope you can succeed with a auto engine! Technology on them has come such a long way compared to certified engines and they are fractions of the price! Keep up the good work!
@@thomasaltruda
So why do you imagine that Continental Aerospace Technologies have taken a stock factory Mercedes-Benz 3.0 litre V6 diesel and converted it into their newest certified aircraft engine, the CD-300, which is technically very similar to the Audi/Porsche/VW 3.0 litre V6 diesel in the Raptor.
The answer is that TCM, as they then were, have been manufacturing the CD-135 and CD-155, now developed into the CD-170, for about a decade and they have turned out to have about the same number of in flight shut downs as turboprops.
www.continental.aero/diesel/engines/cd300.aspx
@@rustyshackleford7022 air cooled vw engines come to mind readily.
I had the unfortunate event of a piston arm breaking inside my engine (truck engine) and the crankshaft popped thru the blocked.
Bummer! So sorry to hear about your engine. Glad to hear you still have your sense of humour.
With the amount of oil pouring out and the engine completely shutting down, I thought the odds were going to be high that that would be the result. it's a setback, but you will get past it. It could have been much worse.
Hello Peter.
You have not considered using the RED A05 / V6 engine
That looks like a nice engine, and unfortunately also a very expensive one. The thing with the Raptor was to use an inexpensive engine that could be easily found and purchased.
As far as I can get the project philosophy itself was to use an engine from automotive. The reason it's because it's easier to find, cheaper, and it's not so complicated to do maintenance and to adapt to different gauges manifolds for both intake and exhaust and a FADEC ECU suitable for an airplane. The VW TD V6 engine it's one of the most common available V6 around in the US alongside some Ford and Dodge quite similar models.
@@hansroemerszoonvanderbrikk7626 What is the reliability of an automobile engine in aviation? I think the VW TD V6 engine will not be able to work for a long time under load. Has life restarted?
Is the Continental CD-300 Jet-A expensive too?
Peter good luck!
@@mauricewalter4739 Usually a diesel engine it's quite reliable, what makes it less reliable it's typically the turbo setup, the intercooler, and continuous accelerations and pressure stress.
The stress on a plane it's not made by fast accelerations but by the duty itself.
If you stay within the designed power parameters you can obtain a lot of duty hours, usually many more than a petrol engine.
Consider that a diesel car could achieve half a million KM without major issues, a petrol engine is going to suffer at half that mileage.
Also, the over head camshafts are no longer as fragile as the first ones, the ones with chains proven to be even more reliable than the plain old rod and over head balancers due to a very precise valve timing, and they also allow to offset the timing to achieve variable combustion ratios.
If you create a proper map on the FADEC ECU and you correctly cool the turbo the overall reliability should be higher than a petrol aircraft engine.
Maybe rod bearing gone ?
All part of the failure cascade: Loss of oil pressure = spin the bearing = rod bottom end starts pounding = breaks a rod bolt = if you are lucky, rod and piston stay at the top of the compression stroke and let the engine continue to turn.
I am glad you were able to make it back to the airport. Press on ! We are all pulling for you.
Very glad to hear that a new engine will be going in. Given what you know now about the thermostat etc etc, would this be an opportunity to simplify the cooling system somewhat? Seems to me that quite a lot of complexity and weight has been added during recent work, and some of it may not now be necessary. Simpler is better.
Is now a good time to noodle about cooling options since you may have some down time?
I’m very sorry that you have had this unwanted extra work. I admire your perseverance.
I realize you had much more important things going on, but did you not hear that rod, or maybe even on the recordings . Also how much is a prop that feathers ? Btw, l still luv the combo of sound of that Diesel and prop . Also the concept and implementation thereof .
Yes, watching the video when the engine quit make me wish for a feathering prop. Even so, the Raptor made an impressive glider!
Ahhh Peter I'm gutted for you, but good that it happened now and not later in the program. I hope all goes well with the engine swap 👍🏽
How about using a turbo prop engine 🤔
All because of a 1.00 part
Hi peter, good job in isolating the problems. I'm curious to know how you fixed the fin on the bottom of the wing that scraped the runway when you came in for the emergency landing.
One oil leak and you blow out the turbos and the engine... may want to have separate oil systems for the units.
Great idea it’s never good when you starve an engine from oil or you think it might have been a new motor will be good give you a lot more information and you’ve learned a lot from the first situation so when you go into production you will know where to watch the issues are it’s just part of this game
Sorry for the setback mate. But glad you’re on the ground safe, and sound!
Thanks for sharing this news. Great positive attitude. Keep it up!
Wow, great great great video! 100% awesome Peter. You get a POB Pat On the BACK!
You Peter are a force for good. You are providing education that is second to NONE!! Beers on me.
Sad this was an avoidable mistake but it is what it is. There's worse things in life.
Use a decent turbo charger lot of good manufactures out there. Don't use crappy Chinese turbo chargers like Sonex does on their VW aerovee. I love how you went with a modern diesel engine just ignore all these people who keep saying use a 70 year old aircraft engine.
Since you had to remove it and you bought an entirely new turbo anyways, it probably would have been a good idea to size them appropriately in the meantime. There are a lot of very knowledgeable people trying to help you and it appears you just love beating this horse.
Hey Raptorman! Just glad you OK from last flight! We have no doubts you'll be flying again soon!
Hey Peter. While u r waiting for the new engine, why don't u try to overhaul this one and create a separate video series.
Possibly (??) Peter needs, for the moment, to conserve cash. But I DO absolutely agree with you.
This is a piston engine, right? Flat four or six?
V6
Won't the 40hrs have to start again with the new engine?
Thanks
Good question. I'd also like to hear the answer to this.
The redrive should have its own oil supply and not share with the engine.
I just had to rebuild a $5,000 motor with 100 miles on it for a similar little problem that cascaded into a spun bearing as well. I am so sorry you experienced the same kind of thing. Adapt and overcome, you got this and I'm sure it'll be better than ever before.
Wow so sorry Peter. :-(
If you're going to swap out the engine, would you please consider checking the other turbo (center section as well?) Perhaps it's alright, however with that level of damage, I think its prudent to pursue that level of detailed inspection.
The last thing you need on the next flight is for a turbo to spit any debris (large or fine) into the intercooler of unknown size and possibly have it make it's way into the combustion chambers.
All the best,
Mo-
You think that the piston becoming disconnected was due to the prop over-speeding the engine? Is there a way to keep that from happening?
That engine runs much faster (higher revs) in Diesel race-car applications, methinks.
I am always surprised at how fast they run them as Diesel race-car engines.
@@johnlichtenstein6158 Makes sense. It would need some kind of mechanical override for that... Good point.
@@SnowAndrews I hear you. It will be interesting to see what the failure mode of that rod / piston was.
@@SomeGuyInSandy .
Agreed.
On another topic I here a lot of commentary from
People obviously familiar with Fords, Chevs, Gasoline auto engines, etc.
who, I suspect, have no experience of European Diesel Auto engines
(in terms of sleeves & re-buildability)
durability, etc.,
and who would be well advised to WAIT & SEE
before playing "Mr. Instant Expert"
(NOT referring to you here !!).
Lots of Wise Guys who have NOTHING invested in the exercise.
and one feels,
little real experience, but rich in instant opinions.
@@SnowAndrews I hear you there too! The idea of a diesel aero engine has a lot of pluses. High torque, low(er) RPM, cheaper fuel... I think it's a great idea.
I thought I seen a spare engine in your shop in Georgia in one of the old videos
I feel your pain, Peter. My beloved Subaru Outback was totaled this week (the other driver’s fault), and I too spent Valentine’s Day alone, working on engineering projects.
have you considered a second oil pump and supply for the prop? Just to isolate potential damage like this.
This might be a great chance to change up the turbo setup! Best wishes
A hyperlapse of the engine swap would be great to see...
I really feel you should look for some causes of why you’re having failures on this relatively new engine. I believe you need to address the overheating problem. Heat stress can cause turbo failure, oil leaks, seal failure which all can be compromised by overheated oil and higher pressure. Would it be a bad idea to have someone consult you on ducting air appropriately through this engine bay to keep it well under the heat limits instead of operating at the top of the temperature limits.
@@stevenhorne5089 He was given the reason for the high heat by an Audi engineer, which is poor twin turbo design & setup. He mitigated it by detuning the boost and adding a bunch of cooling. He didn't fix the root cause of the overheat tho.
@@johngoscinski1995 Hey John. Checking the Audi TDI diesel recommendations with turbos, the ideal operating temperatures are 102 Celsius to 110 Celsius. This is 210 to 230°F. I really love what raptor is trying to do but it seems they’re modifying their flight testing to keep the oil temperature below 240. I’m concerned someone flying the plane within normal climb maneuvering rates on takeoff at what most other aircraft will do in this category will be pushing the oil temps over those temp limits for longer periods of time. I think it is a fundamental cooling problem that should be easy to address by modifying the way the engine compartment and additional oil cooling radiators are operating at all times. When operating this engine on the ground during the summer, it would not operate under 240°. That’s an issue. What if stuck on an airstrip in line for an hour on a hot day then has to take off and climb out rapidly? My belief is he needs to rebuild the engine cooling set up from the ground up for all flight and taxi situations. This will probably need the addition of fans as well as a better design method of moving air efficiently through the aircraft and the engine compartment. My guess is bigger radiators, better ducting and the addition of fans for taxi in hot weather. If you start out on the ground at the upper limits the plane is being stressed during climb. . Better have the plane leaving the ground well within limits. Building a cooling system now will be a hell of a lot cheaper and safer than buying new engines after they fail.
Where is your new engine coming from? I thought the 3.0 TDI was recalled in the US (Dieselgate) and VW/Audi isn’t going to sell TDIs in the US anymore, having committed instead to electric powertrain development. Doesn’t that make availability of replacement engines a problem in the future?
Do you write down each thing you disconnect from the engine as you remove them? Goodness knows I would have to.
He has had this thing together and apart many many times now, but yes a list or even a video while you work helps
Ball bearing turbos on an airplane engine, loosing the dampening of regular journal bearing turbo and adding cost without any benefits.
Best of luck to you