What would Aircraft be like if there were no Jet Engines?

[DB]

OK, so rockets are a thing, but for the purposes of this What if, imagine that we're stuck with internal combustion engines. What does the next generation of "superfighters" look like? What technical limits need to be beaten to death with the slide rule?

 

[sunday]

I think the most sever one would be propellers tips operating in the transonic regime. Or, perhaps the Caproni-Campini N. 1 is not a dead end anymore.

There is the complexity of big alternative engines. Crews of Iberia, the Spanish flag carrier, used to say the Lockheed Constellation was the best tri-motor in the world, as it was nor rare for a engine to fail in flight.

[Tim Sielbeck]

Some variation of this:

 

[Markus Becker]

They'd have engines with so called power recovery turbines. An experimental version of the Allison V-1710 had one. I don't recall the exact bhp but it's pretty wild considering what the engine started with. 

[JWB]

That is the ultimate design of airframes.

Engines would be H-24 layout:

Recovery turbines are highly useful but are more suited for bombers and transports because they operate in a narrow rpm range. More useful is staged turbocharging. 

[sunday]

20 minutes ago, Markus Becker said:

They'd have engines with so called power recovery turbines. An experimental version of the Allison V-1710 had one. I don't recall the exact bhp but it's pretty wild considering what the engine started with. 

Wright R-3350 Turbo Compound

https://en.wikipedia.org/wiki/Wright_R-3350_Duplex-Cyclone

[shep854]

10 minutes ago, sunday said:

Wright R-3350 Turbo Compound

https://en.wikipedia.org/wiki/Wright_R-3350_Duplex-Cyclone

Then there was the Flying Corncob.  I think the Brits were working on similar mad-sized engines:

 

[sunday]

The Napier Nomad would have been the English answer to the Turbo Compound, because of the recovery of exhaust energy.

https://en.wikipedia.org/wiki/Napier_Nomad

[DB]

I was wondering how long before we got to the Nomad.

What about ducted props, like the Italian claimed first jet?

Can one mitigate for supersonic tip speeds?

[Markus Becker]

V-1710: 2000 bhp at take off, 2550 at war emergency power at 20k feet. 

Truly amazing given where the engine came from. 

[Markus Becker]

5 hours ago, sunday said:

Wright R-3350 Turbo Compound

https://en.wikipedia.org/wiki/Wright_R-3350_Duplex-Cyclone

Maybe the double Allison gets another shot too. The B-29 version with that engine exceeded 400 mph and that was without the power recovery turbine. 

 

[Burncycle360]

Also look at current racing aircraft.  You'll see mustang and bearcat like critters with contra rotating props

[sunday]

1 hour ago, Markus Becker said:

Maybe the double Allison gets another shot too. The B-29 version with that engine exceeded 400 mph and that was without the power recovery turbine. 

 

The B-50 was the ultimate version of the B-29, once the fault-prone R-3350s were replaced by P&W R-4360s.

[Tim Sielbeck]

13 minutes ago, sunday said:

The B-50 was the ultimate version of the B-29, once the fault-prone R-3350s were replaced by P&W R-4360s.

That's what my dad, a former B-29/50 and KC-97 pilot, told me many years ago.

[Markus Becker]

18 minutes ago, sunday said:

The B-50 was the ultimate version of the B-29, once the fault-prone R-3350s were replaced by P&W R-4360s.

Was but who knows what might have happened if the V-1710 and V-3420 had been continued?  

[seahawk]

Most likely it would be a twin engine design, because you would still want a nose with volume for a radar and the ability to carry plenty missiles.

[Stuart Galbraith]

15 hours ago, JWB said:

That is the ultimate design of airframes.

 

As long as you didnt mind flying sideways at high speed.....

[sunday]

10 hours ago, Markus Becker said:

Was but who knows what might have happened if the V-1710 and V-3420 had been continued?  

That is assuming large liquid-cooled inline engines were not a dead end - most, if not all, of the "superprop" fighters that were started to be designed in late WWII used air-cooled radial engines.

There is also the sad story of the DB-606 to consider.

Napier Nomad could be an exception, however.

[futon]

[JWB]

17 hours ago, sunday said:

The B-50 was the ultimate version of the B-29, once the fault-prone R-3350s were replaced by P&W R-4360s.

The ultimate version was cancelled.

https://en.wikipedia.org/wiki/Boeing_B-54