What if the WANKEL engine had been invented in WW II?

[Burmese Bandit]

Yes - exactly the point. In war the point is not to design something that is technically brilliant. It is to design something that will win the war, period.

A turbo compound is complex. Wankels are dirt cheap to make, compared to pistons. The turbo compound for an engine would probably cost as much as the bare engine itself. The auxiliary wankel, about a quarter.

When the turbo compound breaks down the whole engine has to be taken out to be replaced. Wankels are small and light. Just junk the damn thing and slap in a new one.

And since we get a total of 2000 hp in an 8000 lb aircraft...that's even better hp to weight ration than the rare bear! The performance would, for a brief time, blow away all the competition!

And in combat, that brief time is all you need to clean the other guy's clock.

 

[Clay_Allison]

Yes - exactly the point. In war the point is not to design something that is technically brilliant. It is to design something that will win the war, period.

A turbo compound is complex. Wankels are dirt cheap to make, compared to pistons. The turbo compound for an engine would probably cost as much as the bare engine itself. The auxiliary wankel, about a quarter.

When the turbo compound breaks down the whole engine has to be taken out to be replaced. Wankels are small and light. Just junk the damn thing and slap in a new one.

And since we get a total of 2000 hp in an 8000 lb aircraft...that's even better hp to weight ration than the rare bear! The performance would, for a brief time, blow away all the competition!

And in combat, that brief time is all you need to clean the other guy's clock.

Ok, the little exhaust eating turbines that make a turbo-compound engine are very simple and very unlikely to break down. They just needed the high heat alloys to start making them at the end of the war.

Very well. Let us say that the rotary WAS theoretically possible to design and build cheaply during WWII.

I agree as long as I accept this premise but I'm not sure that I do. Considering how hard it is to make seals work even now, I don't know if you'd ever get them to hold compression in the 1940s

 

[Burmese Bandit]

Clay, I think all the hands-on people would agree that if you accepted a service life of 20 hours for a 1942 wankel, the engine would be quite plausible.

If you used the engine, as I pointed out above, for only 30 minutes a sortie, that's 40 sorties. (That is being generous, by the way. I suspect you would need to use the 'Wankel boost' for only 15 minutes total on the average sortie)

Most WW II fighter aircraft were dead anyway after 40 sorties. That's why Germany and other nations had to produce 1-2000 fighter planes a month just to keep their fighter numbers from going down!

So in practical combat terms, the short life of a Wankel is no problem at all.

 

[Clay_Allison]

Clay, I think all the hands-on people would agree that if you accepted a service life of 20 hours for a 1942 wankel, the engine would be quite plausible.

If you used the engine, as I pointed out above, for only 30 minutes a sortie, that's 40 sorties. (That is being generous, by the way. I suspect you would need to use the 'Wankel boost' for only 15 minutes total on the average sortie)

Most WW II fighter aircraft were dead anyway after 40 sorties. That's why Germany and other nations had to produce 1-2000 fighter planes a month just to keep their fighter numbers from going down!

So in practical combat terms, the short life of a Wankel is no problem at all.

Alright, I'll say it's a reasonable idea. Would have been well worth experimentation and trials.

 

[The Basket]

Was there a good rotary available to be used in WW2?

Going on the Mazda RX8...high fuel consumption and high oil consumption...and that is in the 21st century.

Why don't all car mnufacturers use Wankels today? Coz they work far better on paper than for real. Aero engineers know there stuff so if wankels are not widespread then that is the reason.

 

[Clay_Allison]

Was there a good rotary available to be used in WW2?

Going on the Mazda RX8...high fuel consumption and high oil consumption...and that is in the 21st century.

Why don't all car mnufacturers use Wankels today? Coz they work far better on paper than for real. Aero engineers know there stuff so if wankels are not widespread then that is the reason.

Wankels are actually used in a lot of applications, just not for the main engine on a car. If the metalurgy existed to make them back then as a disposable auxilliary boost unit, it would have been worth trials.