Automotive based Certified aircraft engine, thoughts?

exncsurfer

Pattern Altitude
Joined
Sep 15, 2014
Messages
2,155
Location
NC
Display Name

Display name:
exncsurfer
What are your thoughts on this new automotive based certified aircraft engine being developed.

It looks promising. Their grabber from the web site:

PUSH BUTTON START
NO CARBURATOR HEAT.
NO MIXTURE.
NO RUN UP.

JUST FLY...

https://corsairpower.com/
 
That 'no run up' seems off.... :)
 
Their grabber from the web site:

PUSH BUTTON START
NO CARBURATOR HEAT.
NO MIXTURE.
NO RUN UP.

JUST FLY...

https://corsairpower.com/

Not in this lifetime
NOT WITH A BUDGET LESS THAN A HOUSE.
NOT FOR YOUR PLANE UNLESS A SPECIFIC CESSNA.
NO CAR ENGINE HAS YET WORKED.

JUST FLY SOMETHING NOT PIE IN THE SKY...
 
Last edited:
This looks more promising than other attempts. They have a prototype up and running, seemed to have taken a few moments and thought a few things out, have a source that won't disappear tomorrow. It might be a good alternative for experimental application. Getting to the certified world is not only the technical "will it work hurdle", but the money for the regulatory processing will add a lot of cost, and then we're back to just using the traditional Lycoming.
 
Umm... it's already been done. Diamond has their take on the Mercedes engines.

Yup.
And here's Diamond's take on how to keep those Mercedes conversions firmly attached to a DA42 airframe, in case anybody "can't understand why it hasn't been done already" (pictured are just two of the tethers on each engine). When was the last time most of us needed these for our Lycoming or Continental?

If auto conversions were a truly workable idea for light aircraft there would be many thousands of them in the air already. There's good reasons why it's a lot more challenging to make it work than it appears.

IMG_0263.JPG

IMG_0265.JPG
 
Last edited:
This looks more promising than other attempts. They have a prototype up and running...

I've lost count of the number of working prototype motors I've seen at Oshkosh over the decades...
 
I just don’t see the point. Most airports already won’t sell mogas to the thousands of airplanes approved for it.

I just did a search. There isn't a field that sells mogas within at least 200 miles of my home field. I'd bet trying to plan a x/c flight would be interesting.
 
Based on this recent litany of failed ideas and paper airplane engines... I'd say it's far easier to make a website about an engine than to make the engine itself.
They make websites for whole unmade or untested airplanes, too.
 
I just don’t see the point. Most airports already won’t sell mogas to the thousands of airplanes approved for it. The engines they start with need extensive modifications that drive the price way up, while competing with one of the least expensive certified piston engines. The spare parts situation is a problem, they will have a default monopoly on everything and likely charge unpalatable prices. Or if they somehow send everyone to GM dealers for most of the stuff their inability to make it through hard years will put owners in a bind.

The Corsair engine in the OP can run avgas.
 
Umm... it's already been done. Diamond has their take on the Mercedes engines.

The Diamond aircraft Diesel engine is severely different then originally configured. It is not a Mercedes diesel transplanted to an aircraft.

Nice write-up on the Austro SE300 engine
https://www.australianflying.com.au/news/diamond-diesel

The foundation of the engine started as a Mercedes block, but departs quickly from there.

“The Austro engine, which is built by a consortium backed directly by Diamond Aircraft, Daimler Benz and Bosch, builds on a similar Mercedes block with numerous improvements.”
 
Last edited:
Yes, but half the the revolutionary benefits they claim come from running mogas.

Looking through the Corsair website, it seems like their EFI system and digital controls are where the biggest advancements are. They took those two systems, and integrated with an aluminum V-8.

Seems like they could have got all of the same benefits, with fewer drawbacks, if they integrated their EFI and digital controls with a more traditional Lycoming powerplant?

Or am I missing something?
 
And the Corsair in the original post isn't?

It looks like the Corsair leverage a lot of the original GM LS3 engineering. All Austro used was the diesel block, everything else was redesigned for aviation duty.

I’m OK being wrong, but this was my understanding.
 
Last edited:
Seems like they could have got all of the same benefits, with fewer drawbacks, if they integrated their EFI and digital controls with a more traditional Lycoming powerplant?

Or am I missing something?
Lycoming did it about 15 years ago already. Expensive, and conversions need certification, adding more expense, so it's mostly limited to kitplanes, and the Tecnam P2012 Traveller, a twin.

ie2.png

https://www.lycoming.com/engines/ie2
 
It looks like the Corsair leverage a lot of the original GM LS3 engineering. All Austro used was the diesel block, everything else was redesigned for aviation duty.

I’m OK being wrong, but this was my understanding.

I suspect a lot of early Diamond Austro owners wish that was the case. The block and internals seem up to the task (although they are supposed to be scrapped at TBO and not overhauled).

It's the accessories that have plagued the engine with problems as many, including alternators, fuel injection pumps, voltage regulators and dampeners, began failing well before expected/published service life limits. Some of this seems to be auto accessories that are not up to the demands of continuous high output aviation service.

One recent example is the fuel injectors. A mandatory service bulletin (that became an AD in Europe) came out in late 2018 putting a 900 hour service life limit on the injectors. https://austroengine.at/uploads/pdf/MSBE4025.pdf

This is what the Bosch-made Mercedes injectors look like...quite different from those little things you get from GAMI for our Lycs and Contis. Each one is flow tested by Bosch and engraved with a number. That flow test number has to be entered into the Austro engine computer, to ensure correct air/fuel ratio, by authorized maintenance personnel who can access the software.

IMG_0713.JPG

Some of the reaction at the time from owners wasn't all that positive.

Diamond/Austro seems to have persevered, attacked and steadily improved the overall reliability. But they have been an expensive engine for many owners to keep maintained, beyond any net gain from the fuel economy and airframe efficiency.
 
Last edited:
I suspect a lot of early Diamond Austro owners wish that was the case. The block and internals seem up to the task (although they are supposed to be scrapped at TBO and not overhauled).

It's the accessories that have plagued the engine with problems as many, including alternators, fuel injection pumps, voltage regulators and dampeners, began failing well before expected/published service life limits. Some of this seems to be auto accessories that are not up to the demands of continuous high output aviation service.

One recent example is the fuel injectors. A mandatory service bulletin (that became an AD in Europe) came out in late 2018 putting a 900 hour service life limit on the injectors. https://austroengine.at/uploads/pdf/MSBE4025.pdf

This is what the Bosch-made Mercedes injectors look like...quite different from those little things you get from GAMI for our Lycs and Contis. Each one is flow tested by Bosch and engraved with a number. That flow test number has to be entered into the Austro engine computer, to ensure correct air/fuel ratio, by authorized maintenance personnel who can access the software.

View attachment 95285

Some of the reaction at the time from owners wasn't all that positive.

Diamond/Austro seems to have persevered, attacked and steadily improved the overall reliability. But they have been an expensive engine for many owners to keep maintained, beyond any net gain from the fuel economy and airframe efficiency.

Good info.

The Thielert’s were plagued with problems and had the replacement TBO. They were even worse. Thought the Austro AE300’s did not have the replace at TBO limitation.

Guess it kind of proves the overall point we still have not seen a car engine successful work in an aircraft.
 
Last edited:
...The Thielert’s were plagued with problems and had the replacement TBO. They were even worse. Thought the Austro AE300’s did not have the replace at TBO limitation...

You are correct. The Austro AE300 and AE330 can be overhauled after the 1800 hour TBO. But so many of the Torsion Vibration Dampers and gearboxes are failing before TBO that most owners at TBO are installing completely overhauled by Austro exchange engines now - so it's a reset-the-clock engine for the 600 and 900 hour inspection cycles.

A new TVD is $5000 if its out of warranty, and many were failing at the 600 hour inspection, so that becomes a major op cost to get to the 1800 hour TBO.

The TVD flywheel for the E4P engine in the DA62 must be inspected at 300 hours and mandatory replacement at 600 hours. One presumes this time interval will be extended as Diamond accumulates more operating hours on that slightly higher power engine.
 
Last edited:
You are correct. The Austro AE300 and AE330 can be overhauled after the 1800 hour TBO. But so many of the Torsion Vibration Dampers and gearboxes are failing before TBO that most owners at TBO are installing completely overhauled by Austro exchange engines now - so it's a reset-the-clock engine for the 600 and 900 hour inspection cycles.

A new TVD is $5000 if its out of warranty, and many were failing at the 600 hour inspection, so that becomes a major op cost to get to the 1800 hour TBO.

The TVD flywheel for the E4P engine in the DA62 must be inspected at 300 hours and mandatory replacement at 600 hours. One presumes this time interval will be extended as Diamond accumulates more operating hours on that slightly higher power engine.

Good grief! A plane owners nightmare. And this is pointed to as the success high point for diesel and car based technology?
 
Good grief! A plane owners nightmare. And this is pointed to as the success high point for diesel and car based technology?

Diamond and the owners with these engines have to get high marks for perseverance.

Mercedes doesn't make or use these engines any more, so Austro has had to start manufacturing the cores. The loss of scale manufacting support isn't helpful. I believe Austro has more than 1500 of the AE300 units in service now, but these numbers are tiny compared to the volume Mercedes used.

The engineering effort to push out the TBO to 1800 hours over an 8 year development period is significant.
Converting a mass produced auto engine may seem "obvious" but the challenges to make it work at aircraft reliability expectations are not trivial. The proof of that is how few auto conversions are out there flying even in the experimental-homebuilt world.

I just wish it was easier and more economical to retrofit better ignition and fuel management systems on to our air cooled motors. Variable spark advance and more precise air/fuel control would make a big difference in performance and fuel economy.
 
Diamond and the owners with these engines have to get high marks for perseverance.

Mercedes doesn't make or use these engines any more, so Austro has had to start manufacturing the cores. The loss of scale manufacting support isn't helpful. I believe Austro has more than 1500 of the AE300 units in service now, but these numbers are tiny compared to the volume Mercedes used.

The engineering effort to push out the TBO to 1800 hours over an 8 year development period is significant.
Converting a mass produced auto engine may seem "obvious" but the challenges to make it work at aircraft reliability expectations are not trivial. The proof of that is how few auto conversions are out there flying even in the experimental-homebuilt world.

I just wish it was easier and more economical to retrofit better ignition and fuel management systems on to our air cooled motors. Variable spark advance and more precise air/fuel control would make a big difference in performance and fuel economy.

:yeahthat:
I hope Corsair gets it done, but it would be a first. And the genesis of this comment: https://www.pilotsofamerica.com/com...aircraft-engine-thoughts.131470/#post-3067263
 
Last edited:
You are correct. The Austro AE300 and AE330 can be overhauled after the 1800 hour TBO. But so many of the Torsion Vibration Dampers and gearboxes are failing before TBO that most owners at TBO are installing completely overhauled by Austro exchange engines now - so it's a reset-the-clock engine for the 600 and 900 hour inspection cycles.

A new TVD is $5000 if its out of warranty, and many were failing at the 600 hour inspection, so that becomes a major op cost to get to the 1800 hour TBO.

The TVD flywheel for the E4P engine in the DA62 must be inspected at 300 hours and mandatory replacement at 600 hours. One presumes this time interval will be extended as Diamond accumulates more operating hours on that slightly higher power engine.
Seems to me that the gearbox itself has a 600-hour TBR. There are hints that it will go to 1200. Some costs: http://www.greatlakesdiamond.com/hourly-engine-reserves-for-da42/
 
The rpm of an airplane engine is limited by the physics of how fast a propeller can turn to generate efficient thrust (tips not supersonic, etc). So you’re always going to need a lot of low rpm torque - which means long stroke large bore under square. Auto engines just aren’t designed that way.

It would seem the next step in engine development - as stated above - would be electronic ignition, individual coils in each plug, etc.
 
So you’re always going to need a lot of low rpm torque - which means long stroke large bore under square.
An old myth that might have been true 80 or 90 years ago. If you look at the TCDS you'll see that Continentals and Lycomings are all oversquare, some of them seriously so.
 
An old myth that might have been true 80 or 90 years ago. If you look at the TCDS you'll see that Continentals and Lycomings are all oversquare, some of them seriously so.
High rpm, short stroke, low torque, low displacement continentals?
 
Back
Top