Auto Engines Aren't Designed to Take Full Power for More Than a Few Minutes...

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wsimpso1

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For those of you who haven’t seen Billski's car:

View attachment 92311

BJC
Nope, no VW for Billski. My wife had one of those, stranded her on the road four times in 80k. Then the exhaust emissions cheating, never again.

Cute concept. I wonder how much they saved with the hole punch versus how much they saved by omitting the interior...

Billski
 

BoKu

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cheapracer

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There's another Luddite on Facebook today screaming "I've been flying for 37 years and auto engines will kill you".

Just mind your own business, why do you even care if it's getting more people up in the air.
 

Hephaestus

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There's another Luddite on Facebook today screaming "I've been flying for 37 years and auto engines will kill you".

Just mind your own business, why do you even care if it's getting more people up in the air.
I have to be Very careful at the eaa to never mention my plan to use a Briggs :)

I'm pretty sure I'll be excommunicated once they hear it run with a prop attached
 

Wanttaja

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There's another Luddite on Facebook today screaming "I've been flying for 37 years and auto engines will kill you".
I certainly agree that auto engines on homebuilts have a reliability issue (45% of all accidents involving auto-engined EAB begin with a loss of engine power, vs. 27% for those powered by traditional aircraft engines). However, the FATALITY rate (percentage of accidents that produce at least one fatality) is actually less. 21.7% for auto engines, 25.9% for traditional engines.

Loss of power is a fundamental aspect of pilot training and a part of every BFR. We generally don't do that bad at it.....

Ron Wanttaja
 

AdrianS

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I certainly agree that auto engines on homebuilts have a reliability issue (45% of all accidents involving auto-engined EAB begin with a loss of engine power, vs. 27% for those powered by traditional aircraft engines). However, the FATALITY rate (percentage of accidents that produce at least one fatality) is actually less. 21.7% for auto engines, 25.9% for traditional engines.

Loss of power is a fundamental aspect of pilot training and a part of every BFR. We generally don't do that bad at it.....

Ron Wanttaja
I seem to recall you posting a bit of a breakdown on this ages ago.

If my memory is correct, it's often installation failures to blame - hoses, wiring, exhaust etc.

And driveline breakages.
 

Hot Wings

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There's another Luddite on Facebook << >>.
Careful with that Luddite word.;) I called my wife that once............:grave:

I too might fall under that label after yesterday.
Ran across a kitchen water faucet that will dispense water in the desired amount and at a desired temperature via voice command and the wave of a hand. I can't imagine any real need or use for such a device - and it's just one more thing to break. :oops:
I have a finger to test temperature and a measuring cup. But I guess if it is enough of a crutch to get one more culinarily ignorant person cooking their own meals then who am I to interfere with someones desires? o_O

Side bar:
Are plumbers now going to be expected to be able to calibrate temperature sensors, flow rate sensors and diagnose network problems to fix a leaky faucet? :beer:
 

Wanttaja

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I seem to recall you posting a bit of a breakdown on this ages ago.

If my memory is correct, it's often installation failures to blame - hoses, wiring, exhaust etc.

And driveline breakages.
The core engines themselves seem sturdy enough (the rate of what I call "Internal engine failures" is about the same as that of traditional aircraft engines. Where the failures come is in what's needed to convert them to aircraft use.
engine_causes.jpg
In my opinion, it's certainly possible to make an automobile conversion that's just as reliable as traditional engines. But what statistics tells us is that the average homebuilder can't achieve that goal.

Ron Wanttaja
 

BJC

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In my opinion, it's certainly possible to make an automobile conversion that's just as reliable as traditional engines. But what statistics tells us is that the average homebuilder can't achieve that goal.
That, Ron, is the key factor about using converted automobile engines in HBA.

Proponents with the skill set (both knowledge and mechanical skills) can be, and have been, successful with conversion engines in HBA.

For those of us without that skill set, all the stuff that needs to be added to and done to the "modern technology" auto engine adds complexity that frequently lowers the FWF package reliability to below that of the "antique technology" aircraft engines. Added weight, which someone here keeps saying is the enemy, frequently is another negative of an auto conversion in an HBA.

Am I anti-auto-conversion in HBA? Not at all. A good, inexpensive, reliable, reasonable weight conversion (in addition to the existing Corvair and VW engines) would be a good thing for sport aviation.


BJC
 

Vigilant1

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Funny unknown is so high and carb ice is so low. That doesn't seem to fit with the GA narrative...
It fits the scenario that by the time the investigator gets around to opening the cowl and checking things out, the ice has melted. So, another "unexplained" loss of power.
In my opinion, it's certainly possible to make an automobile conversion that's just as reliable as traditional engines. But what statistics tells us is that the average homebuilder can't achieve that goal.
"Can't?" or "Didn't?" It seems to me that it is possible, with a lot of attention to detail and (especially) careful attention to what has worked for others in practice.
If folks were doing a lot of one-off homebrew changes to "improve" their certified engines, they'd probably have a lot of failures due to ancillary issues, too.
Interesting that the "other" four strokes (non aircraft, non auto) have about 1/2 the internal failure rate of certified engines. I'm not sure what those engines are, but maybe the little lawnmower engines are as tough in the air as they are on the turf.
 
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