Raptor Aircraft

Hopefully after grenading the engine, he is realizing he needs to dissasemble and clean every oil line, cooler, and the redrive.
 
Hopefully, there’s someone he respects who cares enough to suggest it’s time to hang this thing up.
 
The handling of the engine out was the first time through this whole saga that I've been genuinely impressed with him

I suppose some credit is also due for the sheer tenacity of it all
I guess you missed the part where he has an imminent engine failure (and maybe a fire on the way due to a presumed oil leak) and he agrees to fly a full pattern. His landing on the runway was pure luck (and he won’t last if he keeps relying on it). That was garbage decision making and **** piloting. I’m glad I don’t live under this moron.
 
New engine arrived. 45k miles, 2 previous owners. Who knows how it was treated by them? Who knows how it looks inside? Nobody does and nobody's looking. But he'll ground run it, listen for "weird noises" and if none, start flying again. Better get to it soon, ambient temps are rising.
 
Eh, 45k miles isn't really anything to worry about.
 
Eh, 45k miles isn't really anything to worry about.
Exactly.

12 flight hours out of it and ol' Pete's money ahead. Of the 1st engine, anyway.

Two more engines and that magic 40 is complete.

Cost effective or not: your thoughts?
 
Eh, 45k miles isn't really anything to worry about.

Right. The thing to worry about is why the original engine failed. I'm not going back to watch videos again, but don't remember if a definite cause was identified.

Point is, this engine will fail too unless he fixes the underlying issue.
 
Eh, 45k miles isn't really anything to worry about.
Wasn't suggesting it was something to worry about. Point was it's an unknown quantity. What happened to it during those 45k miles might be important. Maybe nothing bad, maybe ridden hard and put up wet. But that mystery background was true of the first engine, too.
 
I would think that no oil would be the primary cause of engine failure with the seal coming out being the cause on the oil loss.

You're probably right. There are/were so many things wrong with the installation I couldn't remember which one killed the engine.
 
But that mystery background was true of the first engine, too.

I had more to my post originally but this pretty well sums it up. No one expected him to tear this one down, check its condition, refresh it, etc. When his plan is "listen to it and send it," the mileage is pretty irrelevant.
 
You're probably right. There are/were so many things wrong with the installation I couldn't remember which one killed the engine.
Yeah, the engine and install is a mess. I originally thought a teardown was in order but when you think about what happened, I don't think much could be learned from it.

I hadn't thought about it before, but when you buy an aircraft engine, it usually comes with rather detailed maintenance documentation. You know how long it's been in service, how long since the last overhaul, intervals between oil changes, etc. With an auto engine, you get nothing. Not sure how I feel about that.
 
Hasn't that been one of the main premises of this aircraft from the beginning? Using a used auto engine?
 
It’s probably easy to say, since it’s not my money or time...

...but it seems like a prerequisite for using a used auto engine as a base would be a teardown/blueprinting of each engine before being placed in service. Ideally have a team, or even just one person, responsible for having reserve blueprinted engines standing by. With the low cost of the engines, even with such extra work one might still come out way ahead of an aviation powerplant. With the exact condition of each engine unknown, it would seem to make performance figures approximate at best.
 
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I personally can't think of too many automotive engines conversions that have worked out well. Maintenance issues and unforeseen costs usually add up to not being worth the trouble. The few I personally aware of in the experimental world all ended up caving in at the end of the day and installing aviation engines. There is a reason why, despite their often lamented shortcomings, the good old air cooled horizontally opposed engines still dominant the market, and not just because of certification issues.
 
I personally can't think of too many automotive engines conversions that have worked out well. Maintenance issues and unforeseen costs usually add up to not being worth the trouble. The few I personally aware of in the experimental world all ended up caving in at the end of the day and installing aviation engines. There is a reason why, despite their often lamented shortcomings, the good old air cooled horizontally opposed engines still dominant the market, and not just because of certification issues.

The high horsepower auto conversions that I've seen over the years, even if initially an engineering success - and I don't put the Raptor in this category - all seem to suffer the following problems:
- high insurance $, if you can even get it
- no interest from the original engine maker in supporting it for aviation (little volume/high liability)
- A&Ps won't go near them, so the airplane is orphaned once it leaves the original builder
- trouble getting test pilots
 
I had more to my post originally but this pretty well sums it up. No one expected him to tear this one down, check its condition, refresh it, etc. When his plan is "listen to it and send it," the mileage is pretty irrelevant.
Yeah, nobody expects him to do much of anything reasonable, since he has set the bar so low already.
 
Yeah, the engine and install is a mess. I originally thought a teardown was in order but when you think about what happened, I don't think much could be learned from it.
Probably right, but I'd be curious enough to do it anyway. There may be something worthwhile to learn even aside from and unrelated to the failure. I'm not very knowledgeable beyond suck/squeeze/bang/blow, but there could be some evidence of wear/damage from the abuse he put it through before the failure. Maybe not, as it was only a few cumulative hours of abuse, but I'd at least look if I had two weeks to kill waiting for another engine.

But that's not Peter's way. His near total lack of curiosity and his "I'm fine with that" approach to everything precludes any investigation of the condition of the old engine or the new used engine.
 
I personally can't think of too many automotive engines conversions that have worked out well
I think a part of that problem is that they're undertaken by tiny outfits who lack the capital and ability needed, or are pursued in the experimental world for a one off design and are pretty much relegated there. In general car manufacturers don't really care to pursue this anyway given how incredibly puny the market is.. simply not worth it to them

*BUT, Diamond was able to pull off their auto conversion.. the diesel Diamonds are effectively using a heavily modified Merc diesel. So it can be done.. but it can't happen in a garage type workshop

Mooney tried it with Porsche, and that didn't work out either, but I would take that with a grain of salt..
 
I think a part of that problem is that they're undertaken by tiny outfits who lack the capital and ability needed, or are pursued in the experimental world for a one off design and are pretty much relegated there. In general car manufacturers don't really care to pursue this anyway given how incredibly puny the market is.. simply not worth it to them

*BUT, Diamond was able to pull off their auto conversion.. the diesel Diamonds are effectively using a heavily modified Merc diesel. So it can be done.. but it can't happen in a garage type workshop

Mooney tried it with Porsche, and that didn't work out either, but I would take that with a grain of salt..

The problem with almost all of the auto conversions is that they are done under the idea that they will be cheaper to complete than an equivalent aircraft engine. Companies or individuals with no money to start the process will not fare well. I’ve worked for an engine OEM in engine development for 15+ years and know what gets spent on projects. There is no conversion company I am aware of that even comes close to having an adequate budget to make a solid run at this. Even Diamond had problems but it appears they may be sitting better now.

The Diamond project worked because they willed it to work. I think it is less modified than you imply however. Regarding the Porsche/Mooney project, I got the feeling that Porsche didn’t pull out because it was a failure but more so due to the regulatory environment. That project wasn’t the first go at an aviation engine that Porsche/VW was involved in. We just never saw them in the US.

In this case, I think the Audi engine being used is a good place to start. This engine was also used as a basis for a marine engine so it should be suited to sustained, high power settings. The problems that exist will likely all be induced by the individual doing the aviation conversion, as has already been demonstrated.
 
Volkswagon and Corvair engines seem to ave quite a following in aviation circles, but of course those aren't very high power.
 
...but it seems like a prerequisite for using a used auto engine as a base would be a teardown/blueprinting of each engine before being placed in service. Ideally have a team, or even just one person, responsible for having reserve blueprinted engines in standing by. With the low cost of the engines, even with such extra work one might still come out way ahead of an aviation powerplant. With the exact condition of each engine unknown, it would seem to make performance figures approximate at best.
YES! Basically what Diamond/Austro did. Start with an engine, study the living daylights out of it, and then modify it as needed. Unfortunately most outfits though lack the ability to do this and take the much higher risk side of "well, let's just strap it on the plane and see what happens"

I'm continually amazed at how cheap auto engines are.. this engine puts out over 400 hp and can be yours for $13K... holy crap! https://www.roushperformance.com/engines/50l-coyote-sr.html. The T Bones had the big round cowlings.. what a cool garage project that would be to squeeze two of those in a T-Bone. You could run the engines at 50-60% power and still get similar overall cruise figures as the stock engines at 75% power with a much faster climb rate and presumably a higher max gross

one can dream
 
The problem with almost all of the auto conversions is that they are done under the idea that they will be cheaper to complete than an equivalent aircraft engine. Companies or individuals with no money to start the process will not fare well. I’ve worked for an engine OEM in engine development for 15+ years and know what gets spent on projects. There is no conversion company I am aware of that even comes close to having an adequate budget to make a solid run at this. Even Diamond had problems but it appears they may be sitting better now.

The Diamond project worked because they willed it to work. I think it is less modified than you imply however. Regarding the Porsche/Mooney project, I got the feeling that Porsche didn’t pull out because it was a failure but more so due to the regulatory environment. That project wasn’t the first go at an aviation engine that Porsche/VW was involved in. We just never saw them in the US.

In this case, I think the Audi engine being used is a good place to start. This engine was also used as a basis for a marine engine so it should be suited to sustained, high power settings. The problems that exist will likely all be induced by the individual doing the aviation conversion, as has already been demonstrated.
Thanks, I posted the above to fasteddie prior to reading this
 
The issues with the conversions all stem from the engines not being engineered for the intended purpose.

1. They are more often than not liquid cooled, which adds weight and complexity, two things we try to avoid in airplanes.

2. They are designed to provide their peak performance at RPMs that are not usable for direct drive to a propeller. This requires a gearbox to get the output RPM into the appropriate ranges, which again adds weight, complexity, and cost.

I'm sure if the engineer at Audi that designed the engine Pete is running had been hired to create an engine for the Raptor, there are quite a few design choices that would have been different given the different application requirements. Its like buying a Prius to tow a motorhome.
 
*BUT, Diamond was able to pull off their auto conversion.. the diesel Diamonds are effectively using a heavily modified Merc diesel. So it can be done.. but it can't happen in a garage type workshop

Calling the engine that Diamond uses a "auto engine" is the same thing as saying NASCAR runs "stock cars".
 
Thanks, I posted the above to fasteddie prior to reading this

OEM auto engines are cheap due to volume. When you’re dealing with aftermarket automotive performance it is cheap because there is largely no development performed on the parts. In other words, the customer does the “development” for the manufacturer. Not much different than what these auto engine conversion companies are doing...

So, do you want a hot rod car engine with no development coupled to a redrive with no development put in an airframe with no fuel and cooling system development? I’d consider it but I also feel I have a leg up on most builders due to my background. What I would likely end up with wouldn’t be cheap, at which point you might as well start with an engine designed to do the job from the start.
 
Calling the engine that Diamond uses a "auto engine" is the same thing as saying NASCAR runs "stock cars".

From what research and work on them I’ve done I think it is closer to the truth than not.
 
It seems what you want an aircraft engine to do is far enough away from what the car engine is designed to do, there just isn’t a magic bullet that makes it all work.
 
Everyone hear knows about the Mooney Porsche PFM engine based on the popular 911. I don’t think any money was saved going to Porsche for a powerplant, but it did have single lever operation and is reported to run more smoothly than your average Cont./Lyc.
 
So, do you want a hot rod car engine with no development coupled to a redrive with no development put in an airframe with no fuel and cooling system development?
If money was no object it would be a fun, or at least interesting, project.

PS - we often talk about the RPM difference in where an engine is making it's best power (3K-4K) vs prop efficiency around 2K.. however turbofan engines run at higher RPMs and at least one experimental bailed on the redrive and just bolted a "fan" directly to a motorcycle engine.. in the case below the fan is carbon fiber, has 13 blades, and weighs TWO lbs.

Paul Bertorelli:

It's all possible, just need someone crazy (smart?) enough to try it
 
^12,000 RPM! reduction gear to 8,000RPM for the fan
 
Were I going to the trouble and expense of building an entire airplane I'd think I'd want a brand spanking new engine. If that's a discontinued auto engine that can only be found the used market, that's a big strike right there.
 
Were I going to the trouble and expense of building an entire airplane I'd think I'd want a brand spanking new engine. If that's a discontinued auto engine that can only be found the used market, that's a big strike right there.

You see it as a downfall, he sees it as a selling point.
 
Deceased POA member Ben Haas's Ford powered Kitfox seemed to be well engineered and put together.

I got the impression Mr Haas was a race engine guy with a deep understanding of the engine he used and that it would be suitable/awesome in a Kitfox. Also that he was more than skilled enough for the conversion and a clean install. And that it was a labor of love.

Petey is an Audi fanboy, not a gearhead, and his contraption has and will continue to fail.
Petey doesn't have the depth of knowledge, can't maintain relationships with stakeholders that do have the knowledge, and believes that the Raptor project is immune to the realities of physics.
 
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