If a WWII fighter engine were produced with today's technology, what would we get?

[Jack_Hill]

For a WWII a/c replica, an X48 based on the Suzuki 1000 Gsx-r group is, to me, an exciting idea, maybe unexpensive and powerfull.
Wonder if theorical performances could be achieved (2400 Hp and 144 M/Kg torque) with this atmo engine.
Wonder what turbocharging, common crankshaft, boost controls, electronic, final transmission... could add or take to outputs, wheight, reliability, fuel cunsumption an so on...
Wonder about cooling system (12 little coolers or a big common one)
In fact, wonders a lot about.
Could it be sound fitted into a modern, Al, Ti and carbon fiber new fighter or attacker concept ?

 

[GregP]

What did he just say?

 

[Jack_Hill]

Edited, Greg.
Hope clearer.

 

[nuuumannn]

Greg, while I don't doubt your knowledge and exposure to the P-51 and Thunder Mustang, I just don't understand why these guys would put false information on their website. I've also talked to the engineer who maintains that one here in NZ and he also reiterates that it is faster than a P-51. There are two in this country, one of which is at the same airfield as the Thunder Mustang. The warbird community is small here and the number of P-51 drivers number a handful, and if these guys thought these Thunder Mustang guys were talking porkies, they'd say something. Its trumpeted at airshows that its faster. I just don't see why such a thing would be made up. But hey, stranger things have happened eh?

Saw one display to this track at an airshow. Very cool vid as well.


View: https://www.youtube.com/watch?v=OKQyrL0doT4

 

[GregP]

Yeah Jack, that could be a very neat engine. A company like Suzuki, though, would have to see a market for teh product before jumping on board. A private development, ob the other hand. might be able to do it with the right backing. But youa re left with the nagging question, "What is the market so the development effort can pay for itself?"

Reno is sort of winding down and the really fast guys are retiring and their planes aren't being passed along to people whostill want to race just yet. Strega and Voodoo are the two fastest and neither one will be at Reno this year. Maybe if such an engine were developed, there would be some younger guns out there who want to race and have the money to do it.

That would be the gamble in development of such an engine. They'd need a dedicated prop for htht power since the existing props taht can absorb such power are few and far between ... and likely already on an airplane somewhere.

Good luck! I'll watch for it.

Hi Nuuumannn, kitplane makers are always using the highest numbers they can get away with. It's nothing new. All race cars are faster in the story than on the track, too. I have no doubt at all teh Thunder Mustang will out-climb a real one ... it wasn't built for military use and the airframe is tailored for lightness and strength. It's a neat aircraft, but it isn't a warbird ... just looks like one. If you have some there going faster than the real ones, maybe your guys aren't pushing the real P-51's since engines are WAY expensive and propellers are almost non-existing these days. A quality overhaul on a Merlin will purchase a substantial portion of a completed Thunder Mustang.

Here in the USA, we have a 250 knot speed limit at 10,000 feet and below, and most warbirds here, regardlass of capability, usually cruise at 235 knots or below because the owners aren't interested in racing or IFR most of the time. They only fly them for fun on days of severe clear weather. Now, Rod Lewis is different. His airplanes are IFR capable and if he wants to use a warbird to go to a business meeting, he does.

So it is quite likely that a stock P-51D is about 370 mph at sea level on a Merlin if it has stock equipment only. If it has been "cleaned up" a bit, it is probably 385 - 390 mph at sea level. The Reno Thunder Mustang named "Blue Thunder" finished second in Sport Gold in 2012 at 377 mph. The winning Glassair III finished at 393 mph.

These are Reno racers and are not representative of tyeh usual kit Thunder Mustang. They have the money to run the high HP engines. Most Thunder Mustangs aren't running 1,200+ HP, but are pushing the 640 HP Falconer or possibly up to 800 HP. They won't beat a real P-51 and mostly aren't trying to do so. What they do is give the owner the joy of a Mustang at one-tenth the price of a real North American unit.

The Bronze Unlimited winner was Dan Vance in "Lady Jo" (the team owner is a good friend of the museum). He went 330 mph and wasn't pushing it. He bumped to Silver and only went 304 mph in the race becasue he was lapped by Steadfast going 394 mph. Why push your engine when the front runner is 100 mph faster? Steven Hinton qualified at 493 mph in the P-51D Strega and did a 512 mph lap. He won Gold at 477 mph and was pulling power off every 1 or two laps. The big secret to Reno success is to win as slowly as possible and save the engine. If you jump out to a big lead you back off 20 inches for a lap or two and then another 20 inches for another lap or two and make the guys behind you catch up. Hopefully they heat-soak their engines and have to back off. If they can't catch you, keep backing off and win as slowly as possible ... and maybe you can run the same engine NEXT year, too, without too much work on it.

Lady Jo is a two seater with a two seater canopy and only races for fun ... they try not to break anything, but they have a good time at Reno every year.

 

[wuzak]

I don't think motorcycle engines would make a good basis for an aero engine. I think you would have far more reliability issues than with something based on the more solid car engine.

48 is also a lot of cylinders. A lot of maintenance would be required. Also, how many cranks? How many units long?

I think you could make a 10l X-16 based on Ford V8 components. Modify a pair of heads for inverted operation. New crankcase and cylinder blocks, new crankshaft. Gear drive the DOHC system. Add supercharging, and away you go!

 

[fastmongrel]

With modern techniques and materials I would be building a diesel aero engine. We had a car transporter in yesterday dropping off a pair of 2nd hand cars imported from Japan and I got chatting to the driver his vehicle had a 12 liter straight 6 with twin turbos that put out 600hp and used 21 litres per 100km. With that sort of economy you could send a Liberator off on Atlantic patrol and it wouldnt need to come back for 2 days

 

[Balljoint]

The DB 60x had direct fuel injection as I recall. Being mechanical, it was a bit crude and tended to wash the cylinder walls a bit. But it did enhance power.

The issue of flame front travel in a large bore aircraft engine also has a modern answer. Cosworth developed swirl and tumble in the intake charge that, in conjunction with squish areas between the piston and cylinder head, generated intense turbulence in the fuel charge. Fuel burn is increased by the turbulence by around 15X. Perhaps greater in an ultra large bore. Judicious placement of duel ignition plugs could further enhance the burn rate.
The turbo compounded engines were probably the peak development of piston aero engines. But the turbine engine hot section was a better way of generating hot gases than the awkward reciprocating engine so turbo compounding was essentially stillborn.

 

[Jack_Hill]

Greg : sure, Suzuki will never make it.
Only a private team of crazy guys could.
I know racers/replica building is a real tough job.
Warbirds and racers racing are parts of US culture, the lack of proper propellers available should alert some investors I think.

Wuzak :
Yes, a modern car engine base would be good.
Maybe better than a bike one.
And delivering more torque at lower rpm.

Concerning X48 :
Guess light overhauls : fluids dump, spark plugs replacement, filters etc... should occurs after about each 20/35 hours of heavy use (only deducted from a 200Km/h average from a standard 4 cylinders block bike to an estimed 300/ 400Km/h 48X a/c average)
Overhauls, I don't know.
Correct me if needed, I think two cranks would be needed.
Unit lifetime could be long, due to natural ruggeness of this sound concept, but i can't give more precision.

Again, just wondering.
Any more questions or contradictions welcomed.

 

[tomo pauk]

Maybe the best candidate for the modern piston engine would be the turbocharged diesel?

 

[Readie]

Maybe the best candidate for the modern piston engine would be the turbocharged diesel?

A high speed 2 stroke diesel?

 

[CobberKane]

I believe Wankel auto engine are quite popular for use in kit aircraft. Nice and simple, with fewer reciprocating parts than a piston engine. Any design potential for the kind of outputs we are talking about?

 

[wuzak]

I believe Wankel auto engine are quite popular for use in kit aircraft. Nice and simple, with fewer reciprocating parts than a piston engine. Any design potential for the kind of outputs we are talking about?

Not sure how well they scale up.

They can be built in 3 and 4 rotor versions. More than that becomes complicated, unless you use multiple crankshafts joined together.

They do have a tendency towards heavy fuel consumption, however.

 

[tyrodtom]

Not sure how well they scale up.

They can be built in 3 and 4 rotor versions. More than that becomes complicated, unless you use multiple crankshafts joined together.

They do have a tendency towards heavy fuel consumption, however.

I had a Mazda RX3 in the late 70's, it was fast, but it was the oil companies best friend. Oil and gas consumption was very high.

 

[GregP]

The Mazda 3 rotor Wankel didn't ever run quite right for very long ... unlike the simple but small 12A and 13B engines. I've heard of a 4-rotor, but never anyting that suggested it was successful in other than a short race.

I'm not fond of diesels ... but also have never flown one, so I'll refrain from good or bad remarks until such time as I experience one ... or read about such an experience that doesn't somehow end in trouble, like the Thielert debacle.

 

[nuuumannn]

High speed 2 stroke diesel? Napier Nomad!

 

[wuzak]

The Mazda 3 rotor Wankel didn't ever run quite right for very long ... unlike the simple but small 12A and 13B engines. I've heard of a 4-rotor, but never anyting that suggested it was successful in other than a short race.

Mazda won Le Mans with a 4 rotor Wankel in 1991.

Mazda 787B - Wikipedia, the free encyclopedia

 

[MikeGazdik]

I remember when I first saw a cut-away Rolls Royce Merlin. Roller cams, lifters, and knife edged cranks. Stuff that only race cars used in the 1980's, 40 years later.

In the USA, the old V8 "muscle car" engines are still the main source of race engines in circle track and drag racing. I know road racing has other favorites. Just looking at the V8 engine in the USA. Since the late 80's in the racing world, I think the 2 major increases in power has been cylinder head development and fuel management.

I wonder how much power an unlimited Rolls or Allison could make if a completely new cylinder head was made that could be bolted on to existing blocks could be made? The modern engines using digital fuel management are also increasing the horsepower and dependability of race engines. And compared to the times of WWII, the oil technology and bearing material has increased the life of an engine.

I could see a "vintage" 1650 cubic inch Merlin, with modern improvements, making 3000hp reliably.

 

[wuzak]

I remember when I first saw a cut-away Rolls Royce Merlin. Roller cams, lifters, and knife edged cranks. Stuff that only race cars used in the 1980's, 40 years later.

Rolls-Royce Merlins didn't have "roller cams".

No lifters either.

Not sure they had knife edge cranks, but then I am not sure what they are!

 

[wuzak]

See, no lifters or rollers.