Me262 over Korea

Assuming it's engines had been uprated and made reliable, and the aircraft fully developed, would an Me262 still have been able to mix it with a 1950 Meteor, Vampire, Sabre or Mig 15 in Korean war type combat? Or would it have been totally outclassed by then?

[drgondog]

Interesting question and not really predictable w/o looking at some data, specifically wing loading, critical Mach No, and proposed engines.

Off hand I would guess that the MiG and the 86 would be faster, out turn, out dive and out roll the 262 no matter what you replaced the Jumo with as both the 86 and the MiG should be aerodynamically 'cleaner' with the single engines.

It's possible the 262 might acclerate faster initially, and even outclimb, if the thrust of both engines exceeded the Thrust to weight ratio of the 86/MiG 15.

[Graham Boak]

As a first generation jet with a straight wing (yes, it did, in aerodynamic terms) it could have been developed in parallel with the Meteor, F-80 and even F-84 - or indeed the Panther and Banshee. It could not have been made competitive with the later generation fighters such as MiG 15 and Sabre. It's thick straight wing could not compare in top speed, being limited to around 0.82M (I forget the precise number).

Given its design as a heavily-armed high wing-loading bomber destroyer, it could have been pretty murderous to the B-29s, but there's considerable room for doubt over its capabilities in dogfights with even the earlier generation.

[Kutscha]

But Mtt was working on better versions of the 262, and with real swept wings. There was better engines coming as well.

[drgondog]

Even with swept wings and better engines, the two engine wing mounted design would have been an aerodynamic hog, consumed much more fuel per mile of climb/flight. According to Yeager, who flew the 262 after the war, it would not do more than .9-.92 mach in a dive. While sweeping wings might have helped marginally, it was probably more drag related to engines/nacelles than airfoil. There were sound reasons that ALL future high performance twin engine fighters housed the engines in the fuselage

None of the later design twin engine fighters in the late 40's and early 50's could compete with the 86 or MiG 15... so 'new' 262 climb performance and turn performance would have been aligned with thrust to weight and wing loading respectively of the 'newer' Me 262.

I would have to look at the drag profiles and the Mach critical number to have a better feel but would bet large amount that it would be inferior to both except for armament- which does not diminish the importance of this marvelous fighter.

[Graham Boak]

Sorry, but it quite definitely was the aerofoil section that limited the top speed of the Me 262, and 0.92M seems highly optimistic, probably due to a pressure error effect. The engine nacelles being below the wing, they would not have interfered with the fuselage flow in the same was as they did on the P-38, for example. Swept wings would indeed have helped, but the resulting aircraft would not have been a 262.

As for your contention that all high speed twin jets had the engines in the fuselage, what about the multiple variants of the Yak 25 family? The Bristol 188 testbed and the SR71? Or, in more modern times, the Tomcat and the Flanker? Certainly there were many other projects, even if they didn't reach fruition, that retained podded engines.

[drgondog]

Graham - First, I spoke to twin engine fighters and for you perhaps I should have amplified with either 'very successful' or some other less than absolute statement because the Yak 25, while interesting, was not really an example of stellar fighter versus fighter performance.

But it was a fighter and I will grant you the podded engines. They definitely hung from the wings. I accept that correction with good humor.

At the end of the day I wonder how well it would have competed against either the MiG or the F-86 in a furball - which is the question posed relative to the Me-262? It was slower and had dismal high altitude performance - designed to try to shoot down the b-47 and B-52 in air defense role.

Second, the Su-27 and the F-14 are both twin engine swing wing fighters with imbedded engines.. not podded.

As to the SR-71 it is Recon and the YF-12 Interceptor variant was never in production... but it does have podded engines for sure.

The F-4, F-15, the MiG 23, 25, 29, the Jauguar, the Eurofighter, the F-22, the Su 37, the Yak 38, the FA-18, etc, all twin engine Fighters or Fighter Bombers or Interceptors, all have imbedded engines because of weight and drag issues.

Last, I said I don't have the data on the 262, made that comment early, and referenced a source with some credibility on it's maximum Dive speed (which could have been even less than Yeager speculated based on inaccurate pressure readings).

I totally agree that the critical mach for the variants of the Me 262 through the E version were in the .86M range because not enough pitch trim could compensate for the nose down pitch created by lift being lost to compressibility shock over the wings but did you know that the performance for the HIII variant in the wind tunnel was .96 at 40,000 feet?

My comments were focused on a swept wing, 'up engined' state of possible for modern 262 versus Mig and F-86.

Regards,

Bill

[Graham Boak]

The comment about pitch trim is news to me (or perhaps I'd simply forgotten it). As a fairly simple-minded performance engineer I was referring to Mcrit as being the Mach number for drag divergence, which is where the drag stops rising with the square of the speed and shoots upwards dramatically - the "sound barrier". This is caused by the appearance of wave drag from compressibility effects and is a fairly simple relationship between the wing thickness/chord ratio and the point of maximum thickness. The 262 cannot go faster than this because it simply doesn't have the thrust to overcome the drag rise. That bit of extra force provided by gravity in a dive is comparatively small.

I'm sure you're right about windtunnel variants with swept wings, but such a major change to the wing would have required a major rebalancing of the aircraft configurations and I stand by my comment that such an aircraft would not be a 262. No more than a 209 (fighter not racer) was not a 109 despite the clear relationship. In the same sense as a Meteor NF Mk.14 is still a Meteor, or a Spitfire F Mk. 24 is still a Spitfire (by the skin of its teeth!), but an F-84G is not the same aircraft as an F-84F, despite the USAAF designations.

[Graham Boak]

PS The Tomcat has three separate bodies, the engine nacelles being clearly different structures to the central fuselage. The distinction from the integrated design such as the F-15 is clear. The same is true, if slightly less so, for the Flanker.

[drgondog]

Graham - As`a simple aerodynamics (and later structures) engineer I agree 100% with your tutorial on Mach Crit.

I would however suggest you are splitting hairs on discussion of F-14 and Flanker engine housing as 'podded' versus integral to fuselage on the basis of the engine nacelles being 'separate' (for both boundary layer and shock wave considerations)...

The entire discussion centering around the Yak 25/Me 262 'pods' versus F-14 and Su 27 engine mounts philosophy has at least two performance factors, including rolling moment and drag, plus one structural and at least one aerodynamic factor (clean leading edge - SR-71 notwithstanding but that is a completely different discussion) in the favor of the F-15, F-14, Su 27, etc.

Why would you continue to advance the notion of 'podded engines' for the F-14 and Su 27? Help me understand your definition of engine pods in the context of similarities between the 262 and Yak 25 to the F-14/Su 27...

Graham I think the original poster originally postulated an Me 262 'fully developed' (which I interpreted future designs already on the board like the HG II and III with more acute swept wing) and better engines, to ask the question "how would it compete with F-86 and MiG 15, did he not? I have no problem with your argument regarding difficulties posed by sweeping a 262 back to say the 35 degrees planned for the 'HG III' version.. but it was certainly contemplated by uncle Willy.

Intellectually I also agree the original Thud was certainly a different airplane from the F-84A-G variants.. but didn't the 262 outer wing sweep back about 15 degrees making the jump to 35 less of a series distinction rather than new airframe designation altogether?

I will see if I can dig up a respectable source for the Pitch trim deficiency for the 262 dive problems beyond .86 mach. http://en.wikipedia.org/wiki/Me_262

Cheers Graham for your knowledge even though we have some disagreements on this intersting subject.