Auto/Aero engine crossovers

[fannum]

Throughout history, auto engines have been adapted to aircraft, and vice versa.

Note that even the earliest 1898 Balzer engine used by Samuel Langley in his Aerodrome was based on an auto engine. Curtiss' aero engines were developed from his motorcycle racing, and post WWI, Curtiss OX's, Hispano Suiza and Hall-Scott aero engines were used in race cars.
In the aviation boom following Lindbergh's flight, home experimenters and even fully licensed aircraft used Ford Model T, A and V8s, Plymouth and even Crosley auto engines.
Many land speed auto records starting in the '20s used aircraft engines, from Sunbeam, Rolls Royce, Allison to the turbojets used by Breedlove, Arfons and Andy Green's supersonic run.
Then there have been the multitude of auto V8s and V12s used in WWI and WWII replica aircraft, including Chevy V8s used in recreating the replica Vickers Vimy 1919-20 globe girdling series of flights.
Virtually every WWII aircraft engine of any power was put in a tank, from RR V12s to Wright and P&W radials. Many auto engines were used as aux. power units in bombers and transports.
Remember the vaunted Tucker Torpedo used a Franklin helicopter engine to power it,
During the 60s there was a plethora of experiments with Pratt and Whitney, Continental and Rover aircraft turbines in Indy, LeMans and Formula 1 race cars.
Drag racing developed Chrysler Hemis have been adapted to crop dusters, Mercedes diesels certified for light aircraft use by Thielert, and Toyota has tested one of their Lexus aluminum V8s in their own design of a civil four place composite aircraft.
Even the Uber Alles SR-71 Blackbird used Buick nail-head V8 to power the start cart, until parts availability made them change to big-block Chevy V8s.

These are just a few of MANY crossovers. That should be enough to get some discussions and tales going.

 

[Deleted member 68059]

Generally it never works well, and if the finances permit, its nearly always better to make something which is designed for purpose, except for the most basic civil, and training types where cost is almost everything and the performance required is so moderate that the compromises are made invisible.

People do it still because the cost of developing a totally new powerplant today is almost obscene, but from a performance perspective its very demode as a strategy.

It does also depend a little on the intended usage, as if you plan to fly about at very low altitudes many of the problems of adapting auto>aero go away.

Lots of people try this thinking its easy, then get all confused when the ignition system stops working, the fuel boils, the oil foams everywhere, the
engine mounts get fatigue cracks in a few hours, the propeller reduction gear adaptor causes unforeseen torsional vibration horrors and the bearings seize. By the time you fix all that, most people regret not using a purpose built engine. The duty cycles are also almost opposite, and this often causes a formerly reliable engine to turn into a horror which overheats and dies like clockwork.

 

[pbehn]

A high performance sports car needs extensive modification to everything including the engine just to be used regularly for "track days".

 

[MiTasol]

Yep
A friend used a Gershwinder Ford V8 conversion in a couple of Bristol Fighter "replica" and the reduction gear drive chains failed at very low hours on both of them. Recovering the second one from a steep rocky hillside in the middle of nowhere was "fun".

 

[fannum]

Please note that I'm not intending this discussion to become a wrangle about the wisdom of using auto/aero engines for other purposes, but

1) a historical listing of interesting applications (in other writings, I've managed to document many hundreds of crossovers) and

2) the clever and not-so clever engineering required to adapt for the new use.

... Plus whatever other blather the subject inspires.

 

[Deleted member 68059]

Please note that I'm not intending this discussion to become a wrangle about the wisdom of using auto/aero engines for other purposes, but

1) a historical listing of interesting applications (in other writings, I've managed to document many hundreds of crossovers) and

2) the clever and not-so clever engineering required to adapt for the new use.

... Plus whatever other blather the subject inspires.

It might help to post a selection of those cases you`ve documented which you consider the most notable/important/interesting as a starting point. Otherwise nobody has anything to start from other than their general views on the topic.

 

[MiTasol]

The Pietenpols with their Ford Model A engines were definitely a success in their day as were the many homebuilts that used VW engines but I do not know of any modern engines being used. Homebuilts are not my thing so it is well out of my areas of knowledges.

 

[z42]

Mercedes diesels certified for light aircraft use by Thielert

There's also a company called Austro Engines, a spinoff of Diamond Aircraft, that makes aviation diesel engines. My understanding is that the genesis of the company was that Diamond was having some success selling planes with the Thielert engine, but when Thielert went bankrupt they decided to do it themselves. In fact, the Austro AE300/330 (which AFAIU is the only one in volume production?) is based on the same Mercedes OM640 engine as the Thielert engine they were previously using.

Thielert was in the end bought by the same Chinese company that owns Continental, and nowadays the Thielert engines are manufactured under the Continental brand.

Per wikipedia the AE300 clocks in at a modest 0.67 kW/kg, less than half that of many military WWII aviation piston engines. But it's good enough for many GA aircraft, and fuel is a lot cheaper and available at pretty much any airport (it can run on jet fuel in addition to diesel).

 

[RichardSuhkoi]

Generally it never works well, and if the finances permit, its nearly always better to make something which is designed for purpose, except for the most basic civil, and training types where cost is almost everything and the performance required is so moderate that the compromises are made invisible.

People do it still because the cost of developing a totally new powerplant today is almost obscene, but from a performance perspective its very demode as a strategy.

It does also depend a little on the intended usage, as if you plan to fly about at very low altitudes many of the problems of adapting auto>aero go away.

Lots of people try this thinking its easy, then get all confused when the ignition system stops working, the fuel boils, the oil foams everywhere, the
engine mounts get fatigue cracks in a few hours, the propeller reduction gear adaptor causes unforeseen torsional vibration horrors and the bearings seize. By the time you fix all that, most people regret not using a purpose built engine. The duty cycles are also almost opposite, and this often causes a formerly reliable engine to turn into a horror which overheats and dies like clockwork.

I agreed completely with oil system (go to dry sump, add a cooler maybe), reduction gear adapter I think needs complete thrust load decoupling always, and a full dynamics survey. But I'm curious about ignition. Magnetos are inherently reliable, but so can be classic distributors with electronic position sensor and the ignition module fully potted etc. to withstand vibration. The newer coil pans seem to be very reliable so long as kept cool. Are you making reference to high altitude flashover type failures? Just curious.

 

[Deleted member 68059]

I agreed completely with oil system (go to dry sump, add a cooler maybe), reduction gear adapter I think needs complete thrust load decoupling always, and a full dynamics survey. But I'm curious about ignition. Magnetos are inherently reliable, but so can be classic distributors with electronic position sensor and the ignition module fully potted etc. to withstand vibration. The newer coil pans seem to be very reliable so long as kept cool. Are you making reference to high altitude flashover type failures? Just curious.

Yes the dramatic reduction in the dielectric strength of air as you climb can cause a lot of problems. Even coil-over`s may not be immune here depending on how
well they`re sealed, the vibration and pressure difference can mean the little bit of "sea level air" squished about the plug connector to the coil over rubber may
even "fart itself" out up high as you fly and then you can get issues if there is even the slightest flaw in the rubber neck. This tends to only become seriously
problematic above 30,000ft which these days means (if its a new "plane") that its one full of cameras and no pilot... because nobody sensible is offering
light aircraft with pressure cabins and oxygen masks (as far as I know!), not to mention that you`ll never get that high anyway without a massive supercharger or
turbo.

 

[brianwnz]

Well, a few examples off the top of my head; mostly airship engines, crossing over to marine & rail (and vice versa) with one tank example; please don't shoot me if you disagree with the examples, but:

1. DB602, evolved into MB500 series of marine engines. Some changes were made.
2. MAN double-acting marine diesels (exemplified by L11Z19-30), bore fruit with a (much smaller) experimental aviation diesel of the same design, D6Z14-22..... it was never used but it did run. And no, the marine engines weren't particularly good either......
3. Beardmore Tornado - a very similar engine was used in Canadian railcars, with much better success than R-101 engines.
4. The Italian CRM company was looking to install one of their marine W-type diesels in an airship a few decades ago (the Sentinel 1000/5000 project died from memory).
5. Guiberson radial diesels ended up in a lot of tanks in WWII - still the odd one on eBay today even.
6. One model of Junkers aircraft diesels were made after the war by Russia or East Germany I recall, for marine engines.

You can tell I like diesels ...... and I sadly have to admit none were overly spectacular aircraft or airship engines, but perhaps crossed over better into less demanding power-to-weight applications.....

My picks for the better engines would have to be the DB602, and the Guiberson..... and any W-configuration engine, purely on looks. And just to stir the pot, I reckon the Tornado would have got there with a bit more time.......

 

[MiTasol]

THere were other aircraft engines in tanks - The RR Meteor was a Merlin derivative and the Continental W670 radial was used in a lot of tracked vehicles as well. There will be many others - not my area of interest.

 

[GrauGeist]

Packard's 1A2500 engine did end up powering USN PT Boats.

 

[SaparotRob]

Loves me them Elcos.

 

[BobB]

The Wright R-975 had been widely used in aircraft before being adapted for use in the M4 tank. Their power had started at 300 hp and was developed up to 450 hp. Continental took over production of R-975's for tanks, then developed it into a 525 hp helicopter engine used on the Piasecki HUP. After all the HUP's were retired, the R-975-46 engines were cheap since there wasn't much demand for them and some crop dusters used them.
Jacobs developed the O-360 engine for aircraft but Cessna went with the Continental O-300 instead for the 170. Tucker strung Jacobs along for a while before going with the Franklin engine for the Tucker Torpedo. Jacobs did manage to sell some O-360's for Ground Power Units.
Lycoming had moderate success with the O-290 as an aircraft engine before going on to the more successful O-320. They then sold a lot of O-290's for Ground Power Units. When those GPU's were sold surplus, they powered the homebuilt airplane market.