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-   -   Me262 over Korea (http://forum.12oclockhigh.net/showthread.php?t=1598)

The Saint 5th June 2005 23:15

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 13th January 2006 20:04

Re: Me262 over Korea
 
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 15th January 2006 23:39

Re: Me262 over Korea
 
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 19th January 2006 16:11

Re: Me262 over Korea
 
But Mtt was working on better versions of the 262, and with real swept wings. There was better engines coming as well.

drgondog 19th January 2006 18:52

Re: Me262 over Korea
 
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 19th January 2006 22:29

Re: Me262 over Korea
 
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 20th January 2006 19:15

Re: Me262 over Korea
 
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 21st January 2006 01:11

Re: Me262 over Korea
 
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 21st January 2006 01:13

Re: Me262 over Korea
 
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 21st January 2006 02:29

Re: Me262 over Korea
 
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.

Graham Boak 21st January 2006 13:38

Re: Me262 over Korea
 
I agree (impossible not to!) that the F-14 and Flanker are much more sophisticated aerodynamically than a simple podded design such as the 262 or Yak 25/27/29. However, I see them as still being "threebody" designs rather than having the engines fully integrated into the fuselage. The design as a whole is integrated, yes, but clearly a different configuration to that of an F-15 or Tornado, which I would describe as having fully integrated engines and fuselage.

So not a simple wing mounted nacelle, no, but my original purpose was just to suggest that you were being a little too dismissive of three-body solutions in general.

Re Mdd: sorry if I was teaching you what you already knew, but I hope it added something for most users.

drgondog 21st January 2006 18:03

Re: Me262 over Korea
 
Graham - I got 'out of' the airframe biz as a designer in the 70's (F-15 was last 'touch') and on to greater glory in Software and Services. Miss it but financially much better off.

I have a great deal still to learn and sure I will learn some more from you.

I could have been clearer about MY definition lol - but I would have stated jet engines totally encased in a pod/module separate from airframe but would have accepted imbedded in wing like Vulcan, B-45 or SR-71..

Warm Regards,

Bill Marshall

Franek Grabowski 21st January 2006 21:27

Re: Me262 over Korea
 
Quote:

Originally Posted by drgondog
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?

It is all politics. A good example is Hawker Tornado, which when equipped with a new engine, was renamed Typhoon. It was followed by Tempest (which I think was initially called Typhoon II) but here various engine installations were noted only by Mark designations. This is only a sample of such practice, another aircraft being Halifax II/III, Spitfire/Victor, etc.
It depends on ordering side. If they want to buy a new aircraft, the name is changed. If they are allowed to acquire only old types, th name is retained. This was the case of eg. Airacobra.
Best regards

PlaneKrazy 14th April 2006 12:59

Re: Me262 over Korea
 
I would imagine the heavy podded engines on the wing would have a fairly vicious gyroscopic effect whilst rolling in dogfights. The Me 262 was basically designed for speed over slower adversaries and not for dogfights.

Also the Soviets captured at least two intact Me 262s and test flew them, plus several dismantled examples. If they were so good why did the Soviets field the Mig-15 rather than a reverse enngineered Me-262. The answer is self evident that the Mig-15 was superior to the Me-262.

By implication the Me-262 would be cannon fodder for a Sabre.

The Mig was based on the similar German, Focke Wulf Ta-183 design, so the luftwaffe was already thinking of a second generation after the Me-262

Boandlgramer 14th April 2006 16:26

Re: Me262 over Korea
 
me 262 over Korea. ;)
next thread is about "sabres over vietnam 1966 " ?

" By implication the Sabres would be cannon fodder for a Mig 21 .

btw, why do you mean the Mig 15 was based on the Ta 183 ?

Richard T. Eger 15th April 2006 02:33

Re: Me262 over Korea
 
That's the first I'd heard that Chuck Yeager flew an Me 262. Can someone confirm this with a source?

Regards,
Richard

Six Nifty .50s 29th April 2007 10:26

Re: Me262 over Korea
 
The drag penalty of outboard jet engines is an interesting topic. But I would think that structural integrity rather than drag is the main strike against underwing engines. Simplicity and ease of maintenance might be the best reasons to use outboard engine pods.

It prompts me to wonder what sort of violent test pilot maneuvers that a multi-engine jet can withstand before the turbines were pulled off the wings (Me 262, Ar 234, SR-71, B-52, B-58, B-1, etc).

Graham Boak 29th April 2007 16:49

Re: Me262 over Korea
 
You're mixing different structural designs there. The engined mounted in pods on pylons would be likelier to break long before the more integrated designs such as the B-1, or even the 262/234. But it's an irrelevance on the later types, as failure would occur elsewhere first.

The main benefit of the engines on pod is the clean wing, with the pods providing bending relief so permitting a lighter design. But this is for low-g aircraft.

I'd like to step back to Franek's older posting about names. It has not always been a matter of politics, although that certainly was true at times in the US on the 40s and 50s. In the UK, aircraft names depended upon roles, so that the Vickers Vincent general-purpose type was the Vildebeeste torpedo bomber. The Fury went to sea as the Nimrod, the Hart as the Osprey. The bomber Hart became the army co-operation Audax, renamed Hartbees for export to South Africa. In both the US and the UK, it was normal to rename/renumber a type if the engine was changed, the Merlin engined P-51 becoming (initially) the P-78, the Allison-engined B-17 becoming the B-38. Something that was only reduced - not altogether forgotten - in the 40s. So having the Tornado/Typhoon with the same name is rational. The Tempest may have shared the engine and most of the fuselage with the Typhoon, but it had a very different wing. As one designer said, it is the wing that makes the aircraft, the fuselage being just a matter of packaging. (Not true since the need for area ruling, but true enough for the 30s and 40s.) Hence the suggestion that the 20-series Spitfires should have been renamed.

But I don't understand the reference to the Airacobra. There were no significant changes to the P-39 design throughout its life. There was a version for the USN as the Airabonita, but this had a tailwheel and other changes. The P-63 Kingcobra was a significantly different aircraft, with a two-stage engine and a "laminar" flow wing.

Franek Grabowski 29th April 2007 19:13

Re: Me262 over Korea
 
Graham, please note Tempest II and Tempest V or Beaufighter family. It was certainly dependant on government/parliament's policy, either willing to invest in new types or rather to rely on old ones. Concerning Airacobra, after the turbo-compressor was canceled, a new designation had been considered but not implemented after it had been realised there is no money in the budget for new types.

Graham Boak 30th April 2007 01:37

Re: Me262 over Korea
 
[quote=Franek Grabowski;42132]Graham, please note Tempest II and Tempest V or Beaufighter family.


You could also add Wellington, or Sunderland, and I suspect others, to your list but by the start of WW2 it had stopped being the British habit to change the name of an aircraft just because the engine type changed. Given the rate of spend during WW2, economic/political influences were totally irrelevant on the choice of name, if it ever had been. Later, the Hunter, Buccaneer and Victor changed engines without a name change.

I can't think, offhand, of a single example of a British aircraft where the name was kept the same for economic/political reasons. The British system just doesn't work in that manner. It is much more an American habit, because of the US system of annual budget reviews passing through Congress and the Senate. Which might perhaps point the finger at the Harrier II, where a new name would indeed have been justified, but there the pressure would have been to go with the US name - it was 1942 when the British stopped giving aircraft different names than the US. And besides, the name Harrier had a particularly special cachet; perhaps like the Spitfire there was a popular/"political" reason but little to do with our democratic representatives.

Franek Grabowski 30th April 2007 02:20

Re: Me262 over Korea
 
Hmm, could you explain the British system then, please? I thought that the principles of any budget expenses were the same.

CJE 30th April 2007 14:50

Re: Me262 over Korea
 
May I add my two cents to the original question?

The Me 262 was already an outdated model when it first became operational. Its design dated back to the late 30s when absolutely nothing was known about high subsonic flights - not to speak about supersonic flights.
Had war kept raging on in 46, it would have been superseded by more modern types embodying the latest state-of-art technology and aerodynamics.
The subsequent development of the 262 would have been a dead-end issue, because its basic design was just not good enough to make it a potent warplane - something it NEVER was.
Spotting a Me 262F or G or whatever over Korea is just a teenager silly joke.
On which side, incidentally?

Nick Beale 1st May 2007 20:12

Re: Me262 over Korea
 
Quote:

Originally Posted by Graham Boak (Post 42152)
Given the rate of spend during WW2, economic/political influences were totally irrelevant on the choice of name, if it ever had been. Later, the Hunter, Buccaneer and Victor changed engines without a name change.

I can't think, offhand, of a single example of a British aircraft where the name was kept the same for economic/political reasons. The British system just doesn't work in that manner.

Maybe ships are different, though? I remember how the Invincible class aircraft carriers appeared in 1970s defence budgets as "through-deck cruisers" to get them past sceptical politicians.

JoeB 1st May 2007 22:11

Re: Me262 over Korea
 
Quote:

Originally Posted by CJE (Post 42179)
Spotting a Me 262F or G or whatever over Korea is just a teenager silly joke.
On which side, incidentally?

I doubt there were any Me 262's actually used over Korea, by the Communist side, there's no doubt on the other side. However, a number of US pilots reported seeing twin engine jets, generally at night, that they sometimes identified as Me262's. In one case the sighting was after dawn, and the B-26 (Invader, formerly A-26) pilot, who had flown medium bombers in late WWII ETO and seen real Me-262's, said it was an Me 262. The source is primary documents.

These indentifications were likely errors, however what the pilots actually saw in these multiple cases hasn't been otherwise explained. Il-28's are a possiblity. One well known Russian authority on Soviet participation has written that an Il-28 unit flew recon missions over Korea at night late in the war, but that the details are still classified in Russian archives. And for example the Lavochkin design competing with the MiG-15 is reported in some sources to have been evaluated over Korea; it wouldn't be mistaken for an Me-262 of course, but what about other prototype evaluations?Much has been revealed about Soviet ops in Korea but we can't assume everthing has. I doubt those sightings were literally Me-262's, but there could be an interesting story behind them nonetheless.

Joe


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