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

[bob44]

I can see a couple of big things being different today beyond any advances in materials and design. First would be electronics/computers, the second would be emission controls.
The better materials and designs should get more hours and performance out of an engine, but the complex electronics would mean longer/more cost to produce and repair.

 

[nuuumannn]

A big problem with modern aircraft and their avionics issues is not the individual pieces of equipment, but interface between systems. Different manufacturer's software can't always understand each other and isn't compatible and in R D that's the biggest cause of delay with electronic systems of modern aircraft than any other. Look at the Australian Seasprites as an example, other issues aside, of cramming too much gadgetry into an existing airframe in a misguided aim to produce extraordinary capability where it never previously existed and the result is an unuseable aircraft.

 

[gumbyk]

A big problem with modern aircraft and their avionics issues is not the individual pieces of equipment, but interface between systems. Different manufacturer's software can't always understand each other and isn't compatible and in R D that's the biggest cause of delay with electronic systems of modern aircraft than any other. Look at the Australian Seasprites as an example, other issues aside, of cramming too much gadgetry into an existing airframe in a misguided aim to produce extraordinary capability where it never previously existed and the result is an unuseable aircraft.

and the antithesis of this is the RNZAF A4's (when we still had them), Orions, etc

 

[GregP]

An A-4 with modern avionics and a higher-thrust engine with no more weight would be nice huh?

 

[yulzari]

Gimme' a Skyraider with modern avionics, a modern engine of 3,500 HP, and some smart weapons and I'll show you what an attack plane can do! I want the rotary cannons, too! No more rat-tat-tat ... more of a hummmmm ... and target gone. I'd rathre have a turboprop, but if that's out, a piston did just fine in the real beast, so it should do at least as well with a more reliable modern engine.

The snag is that, with the equivalent 3,500 bhp enemy fighter the Skyraider would last as long as a Fairey Battle in 1940 unless you had air supremacy. Witness the death of the dive bomber concept. However, another pair of threads.

 

[Jabberwocky]

Perhaps a closer guide to the use of modern materials and technology is the Formula 1 engine. Simplisticly put, in @1970 it produced 400 bhp at 10k rpm. 40 years later it could put out 950 bhp at 20k rpm (rpm was then limited by the rules.).

This suggests that new materials and ignition control only increased the power from 13.33 bhp per litre per 1k rpm to 15.83 per litre per 1k rpm or barely 19%. The bulk of the total power increase came from the increase in rpm. As the late Keith Duckworth used to say; horsepower is the size of the bang multiplied by the number of bangs per minute.

F1 is not a good comparison, because the engine regulations are TIGHTLY controlled and you're comparing very different styles and size of engine.

A 3.0 liter, naturally aspirated Cosworth DFV in the early 1960s was producing a little over 400 hp at 75000 rpm. By the late 1970s it was producing 535 hp at 11,000 rpm, about 180 hp per liter of displacement.

Fast forward to the early-1980s and you get forced induction (turbocharged) engines. These producing about 800 hp from 1.5 liters, or about 535 hp per liter of displacement, for qualifying and about 720-740 hp for a 2 hour rance. By the end of the turbo-era in the mid 1980, the same 1.5 litre engines are producing 850-900 hp in race trim and over 1300 hp in qualifying trim, or about 865 hp per liter of displacement.

When F1 went back to natural induction, power dropped again. Still the 3 liter V10s were producing 890-930 hp in 2003/2004 at about 19500-19800 rpm, before the engine rpm restrictions. The Ferrari 053 was known to be making 920 hp at peak 19,500 rpm, the Mercedes FO 110 was producing about 910 and the Honda engine was suposed to be making 930 hp, possibly 950 hp in 2005.

Modern F1 engines, limited to 2.4 l and 18,000 rpm, produce about 765 to 780 hp. I've got a copy of a Mercedes dyno sheet showing 956 PS (940 hp) at 18,700 rpm.

 

[GregP]

The original Skyraider would do just fine in any battleield where the opposition didn't have high-tech weapons ... which is MOST battlefields in an insurgency. For a declared war with defined lines ... maybe not. But anyone in Viet Nam who fired on a group of Skyraiders found out that the rest of the guys they didn't hit weren't very happy with them and rather quickly died.

I bet firing on a group of Su-25's produces the same result today unless you have whole s---load of Stingers and fire them all at once. Mostly, if you have these, the flyers will know and the Apaches will vists to reduce your inventory. If you do fire on a group of Su-25's, some Stingers will invariably lock onto the same target unless very well coordinated ... leaving the surviving Su-25's to be very angry with you. When that happens, you want to be anywhere else.

If it's too dangerous for Skyraiders, go visit with Reapers or other attack drones and THEN send in the Skyraiders. The people remaining will not be happy when they leave.

 

[Milosh]

@ 1800rpm and -2lb boost the Merlin consumed 22gph
@ 2000rpm and -2lb boost it was 25gph

Spitfire VIII A58-315

 

[Readie]

I agree about fuel injection and ECU's to get the most power for your bang as it were.
I wonder if the use of modern materials would give any significant weight loss?
So improving the power to weight ratio.
What do you guys think?
Cheers
John

 

[dobbie]

If the engine controls go solid state, communications would follow along? That's going to save some weight and possibly shift weight to a more favorable balance. Getting rid of multiple magnetos and going to crank trigger ignition should save weight too-I'm not certain how distributorless ignition would function at high altitudes, but the only weight gain I can think of would be in the electrical system-higher output alternator/generators with which to power it all.
Adding a rotary cannon is certainly going to add weight and complexity, with a speed penalty on single engine fighters because of where it would have to be mounted. One of the SUU pod setups did operate on a gas action but Im not certain how reliable it was. Wonder how effective a P38 with a 50 cal rotary in the nose might be for ground attack...

 

[dobbie]

I agree about fuel injection and ECU's to get the most power for your bang as it were.
I wonder if the use of modern materials would give any significant weight loss?
So improving the power to weight ratio.
What do you guys think?
Cheers
John

Oh, maybe a carbon fiber Mustang??? NICE!

 

[nuuumannn]

Oh, maybe a carbon fiber Mustang??? NICE!

There already is, the Thunder Mustang, a 3/4 scale one powered by a V-12 and its faster than the original! I've got pics of one somewhere...

 

[GregP]

It is a lot of things, but it isn't faster than the original. They fly in the Reno Sport Class every year and lately had been turning slightly over 400 mph. Originals are faster and the dedicate racer P-51's are more than 100 mph faster.

Stevo Hinton has lapped Reno at 512 mph in Strega. More or less stock Mustangs in the Silver class have lapped at 445 mph or so.

The Thunder Mustang is really neat and I'd LOVE to fly one ... but it's a rich man's kitplane. I'm NOT fond of the Falconer V-12 made from a Jaguar V-12. It is pwoerful, but I've seen 3 let go all at once while racing and the result isn't pretty. The plane flies very well, though, as long as you are proficient in high-performance aircraft.

As an aside, Strega may never race again, but they made a one-piece carbon-fiber cowling and it SHOULD add some more speed to the 512 Stevo ran. Hope they get a chance to show it off. It would be a real shame if Strega never raced again ... but it may be in the cards mainly due to the cost of Reno racing. Nothing to do with not wanting to do so.

 

[nuuumannn]

Hi Greg, well, there's a few areas where the original does outperform the Thunder Mustang, but not by much. Take a look at the specs on this page.

Blue Thunder Air Racing :: Specifications

We have one here, it is the fastest piston engined aircraft in the Southern Hemisphere. Looks real cool, despite the awful weather when I took these.

 

[GregP]

Last time I flew in a Mustang we went up at 2,800 feet per minute at well less than full power, which we never used. Their specs are, shall we say, a bit optimistic.

Love the plane, but it does NOT out perform a Mustang except in rate of climb ... and not by anywhere NEAR the margin in the so-called specs at that. Seen too many of them not to know.

Still wish I had one ... with something other than the Falconer ... he makes a great engine technologically, but the Jaguar V-12 is not exactly a paragon of reliablity in a car much less a plane. Hell, I've only ridden in a Jag V-12 four times and have experienced one engine failure. Last Thunder Mustang crash I saw was a direct result of a blown Falconer V-12 and a 45 knot crosswind ... yeah ... he was going 400+ mph at the time of the failure, so the engien DOES make good power.

The pilot didn't exactly handle the situation in a good manner, but I was impressed that he hit a berm while touchning down where he didn't want to and the gear didn't break off. Must be quite strong! The winner might have been another Thunder Mustang, but the race was called and the Gold Final was cancelled due to high wind.

 

[wuzak]

The Falconer is not a Jag V-12 - it is based on the small block Chevy. So that means pushrod OHV.

The block is custom designed for the job.

Welcome to Ryan Falconer Racing Engines! - Falconer V12 FAQ

They use MoTeC fuel injection - an Australian company that supplies ECUs all over the world, including many motorsport series.

 

[GregP]

When I last saw a Falconer up close, it still had the Jaguar logo and writing on it ... Maybe he makes something else today, but this was early in the Thunder Mustang days, and when Ryan was building Jags ... and ONLY Jags, for the Thunder Mustang. I haven't looked at his engines in 10 years or more, so you are probably correct. But he USED to build Jag V-12's, for the Thunder Mustang.

I knew 3 people who died flying them, 2 in Arizona alone out of Scottsdale. I didn't like Jags much after that untl they started using engines associated with Ford. Ford might or might not be the best in the world, but they didn't fail nearly so often as the Jag V-12 did in everyday service.

I'll look up his website and see what is being built today out of curiosity ...

 

[tyrodtom]

The Jaquar V12 in a 60 degree block overhead cam, the Falconar V12, is a 90 degree block, pushrod engine.
How could it possibly be based on the Jaquar ?

 

[cherry blossom]

When we try to understand why we can get more power out of modern piston engines than WW2 engines of similar capacity, one reason is that we now know slightly more about what is happening inside the cylinders. Three terms that seem to inspire Google are "stratified charge" A textbook of automobile engineering - Rajput - Google Books, swirl and tumble ScienceDirect.com - Progress in Energy and Combustion Science - The effects of swirl and tumble on combustion in spark-ignition engines and http://iffc.cnrs.pprime.fr/slidesWkshp/Boree_IFFCWkshp2010_EIFpaper.pdf. Naturally, the gases were swirling during WW2 and it can be argued that sleeve valve engines gained from induction swirl http://www.enginehistory.org/members/articles/Sleeve.pdf and http://www.amazon.co.uk/dp/B0007JWELC/?tag=dcglabs-20. However, it is all better understood now. I suspect that an engine for a combat aircraft would gain more economy from stratified charge combustion than a modern car because there would be less concern about emissions.

 

[GregP]

Hey Tyrodtom,

When Ryan Falconer started building engines for the kit planes, he started out using Jaguar V-12's for some applications that wanted V-12's. As I stated just above, if he's building something else today then OK but, at one time, he had an engine based on the Jag unit and several folks at Scottsdale airport had them ... two that I know of came to grief flying the Jag-based units.

I see from the Falconer website his new engine is NOT a Jag unit and has a PSRU developed by an old aviation friend, B. J. Schramm (who founded Rotorway) along with Oswald Webb of Great Britain, now retired, who worked on the original Merlin reduction gears. Good for Ryan.

I also see the normally-aspirated unit develops 640 HP and the supercharged uunit belts out 1,200 HP and CAN be hopped up a bit from there. If they can get 1,500 HP from it then there is no reason the Thunder Mustang can't out-perform a real P-51 but the Thunder Mustang was designed to emulate a P-51 ... not a racer like Strega. If he developed an airframe tailored to racing specifically, then he might have something there that could rival the real thing.

However most Thunder Mustang owners want a P-51-like airplane, not a dedicated racer. Racers make awful fun / transportation planes. They have as much equipment removed as possible, less fuel capacity, cooling capacity good for one race, etc. The Reno racer "Race 232," owned by Rod Lewis at present, started life as a Hawker Sea Fury FB.11, but is now a racer only. It can't really go more than about 250 miles before it has to land and top up the fuel and oil cooling system. If running at anything like high power, the ADI and spray bar won't even last for 6 laps at Reno. So if some Thunder Mustang owner wanted to race in the Unlimited Gold bracket, he might stand a chance, but faces some serious airframe modifications. They already KNOW what makes a P-51 go 500 mph and it COULD be done to a Thunder Mustang ... but that's not why you BUY a Thunder Mustang to start with. I'd expect 99%+ Thunder Mustangs to race in the Sport Class since they spend the other 51 weeks a year emulating a real Mustang. Neither Strega nor Voodoo have what could be called a P-51 airfoil anymore. Both have been "profiled." I don't know of anyone who would wanted to spend a lot of time and effort build the kit only to have to chop it up and alter the airfoil just for racing purposes ... but he might be out there somewhere. If so, I'd love to get involved and help!