Me262 vs. P-80

[kool kitty89]

Ok, and I'm pretty sure the P-80 used laminar flow wings. (the P-59 did too, but with wings that large and thick, 45.5ft span 386 ft2 area, this canceled out any low drag benifits... Plus there was the general lack of streamling and wind-tunnel testing durring development; no wonder it ended up a lemon.)

It is interesting though, that no US jet-powered fighter has ever used external engine nacelles, the Airacomet was the closest they got, and even it had the engines incorporated into the wing-fusalage junction...

 

[Glider]

Yes Glider its aerodynamics, and aerodynamics don't support your claim that induced drag is greatly increased with 17.3 degrees of sweep. Get my drift ?

Yep and the drag is increased to some degree

You may doubt it all you want but I do have that information Glider:

Cdi = (Cl^2) / (pi * AR * e)

Try plotting in some figures and see what effect just a 10% increase in AR actually has on induced drag.

Its the 'e' value thats missing for me. DO you know anywhere where these can be obtained? Its not just for this its something that I have looked for.

Is 7.23 not high ? And thats without considering wing sweep.

Nope, not when your used to figures of 16-25 Seriously, you are correct iro aircraft, my mistake.

Its very close to the same Glider.

I wouldn't disagree with this

 

[kool kitty89]

One thing the P-80 certainly had aganst it was the paint scheme, or lack there of. The bare aluminum would have been alot easier to spot than the 262's camo... Though all USAAF planes produced by this time were like this
since they were no longer trying to hide from the LW. Plus the original Pearl-Gray (still not camo) prooved to be too hard to maintain too... But the lack of paint saved a bit on weight ad drag...

Though in Korea this didn't make a difference since the migs were bare too...

 

[Soren]

Glider,

The only way to determine the Oswald Efficiency factor ('e') is with full scale windtunnel tests, so I therefore don't have the accurate figures here either. But e is often very similar between aircraft, esp. of the WW2 era, so I assume that the Me-262 and P-80 have rather similar e values.

Koolkitty,

The Me-262 didn't use laminar type airfoil.

Stitch,

The Germans were fully capable of making laminar flow airfoils, however being well aware of its negative effects on lift and stalling characteristics it was decided not to use it on any a/c.

 

[SoD Stitch]

Stitch,

The Germans were fully capable of making laminar flow airfoils, however being well aware of its negative effects on lift and stalling characteristics it was decided not to use it on any a/c.

I'm sure the Germans were capable of building laminar-flow wings; they were capable of just about anything but, as you pointed out, the benefits did not outweigh the negatives, so it was decided not to pursue that line of development.

And, as I stated above, by the end of the War, the Germans were using any every able bodied person, German or not, to produce war armaments; so the people assembling Me 262's weren't exactly of the highest caliber skill-wise.

 

[Soren]

Another reason for why the Germans did not implement the laminar flow airfoil into their designs was that actually achieving fully laminar flow over the wing was all but impossible back then. First of all the surfaces of the wing had to be kept in absolute perfect condition, no small lumbs or the laminar flow would by ruined, something which was impossible in the field - hence the P-51's in service didn't achieve a full laminar flow over their wings.

 

[syscom3]

The issue of laminar flow wings is the precise tooling needed to build the wings. Tolerances are critical.

NAA figured out a way to build them in a mass production environment. Germany didn't, thus they stayed with the more traditional wings.

 

[Soren]

Thats incorrect Syscom3, the Germans deliberately decided not to use laminar flow airfoils for their designs entirely because of its negative effects.

 

[Kurfürst]

I thought the one that crashed actually crashed up in England at RAF Burtonwood and killed Major Frederic Borsodi.

Hi,

Does anybody have any kind of biograpical data on Borsodi - pictures, aircraft he flew, service record etc? If so, please contact me in email or PM!

 

[delcyros]

Some Ho-IVb flying wings were build with a laminar flow wing and flying in mid 43. Laminar flow wings were considered for the improved Ta-152 and Do-335 but these projects were not carried out.
I too believe that tooling technology in Germany was not improved enough to allow their mass implementation by 44.
Laminar flow wings of otherwise comparable properties will stall both, earlier and more violently (often with direct translation from laminar to seperated flow, bypassing turbulent airflow). In a prolonged turn this is critical and gives the -262 a distinctive advantage (LE-slats furtherly delay the stall to higher AoA-figures).
But I really doubt this plays a role here. The -262 pilot who keeps turn maneuvering until LE-slats deploy will waste his "e" and thus becomes an easy target for others. Staying fast is what increases survivability chances. Turning is ww1 style fighting. The roll charackteristic is not affected by LE-slats and the roll behavior of the 262 cannot be better than the P-80 with all the mass of the engines placed so far outbordly, hands down.
Laminar flow wings do not only allow a lower drag figure but also structural improvements (the wing can be build more stiff or an equally stiff wing can be build lighter) and advantages in wing space (laminar flow wings allow larger wing fuel tanks, one of the major advantages of the P-51).
Finally some words to engine nacelle placements. Early jet engines delivered insufficiant thrust and thus designers had to reduce the AIR INTAKE and EXHOUST losses to optimize the low thrust powerplants. Tests with 6m intake
pipes and 2m exhoust pipes on a Me-262, carried out in feb. 45 for evaluation of the HG program, showed that the losses are 6% thrust for the intake and 3% thrust for the exhoust, respectively.
These intake / exhoust losses are often neglected in thrust / weight or powerload figures of embedded designs as in the P-80 / Vampire.
It is a tradeoff. external mounts (Meteor, He-162, Me-262, Ar-234) add drag but will allow 100% of the nominal thrust of the powerplant and internal mounts cannot always be made as perfect as in the short bodied Ho-IX.

best regards and a merry Christmas,

 

[kool kitty89]

Though the Vampire was a bit better than the P-80 for thrust loss since the twin-boom design allows for a very short jet-pipe. There will still be some intake losses, but they are still somewhat short on the Vampire, though angled.
And don't forget the P-59's semi-fusalage-embeded nacelle configuration, which would also promote minimal loss.

 

[Robin olds]

In real life it goes like this. The P-80, is likely to be faster,more agile in a dogfight but the 262 have far superior firepower and better pilots. In realistic air warfare the aircrafts scores an equal due to better luthwaffe pilots and better guns

 

[Colin1]

I think the numbers speak for themselves. On top of these figures, the Me262 rolled poorly, the P-80 rolled extremely well. The P-80 also out-turned the Me262. I really cannot see any aspect of the Me262 that beats the P-80.

The P-80 would have blasted the Me262 from the skies with ease!

That's the problem with numbers, they're only any good at speaking for themselves.

The F86 wasn't as fast as the MiG-15, it wasn't as heavily armed and couldn't climb anywhere near as rapidly; three key attributes in air combat. Despite this, the kill ratio of F86:MiG-15 was about 1:13 if you included MiG pilots of all nationalities involved (Chinese, Korean and Russian).

In yet another twist, this is unlikely to have been the case in the ETO where the USAAF squadrons had gotten pretty competent at taking on the Luftwaffe. Their personal piloting attributes generally and team skills by this stage of the war would have allowed them to maximise the advantages of the F80 against the Me262 whilst the same would have prevented the Luftwaffe from deploying its own experience decisively.

The strategic advantage (near-uninterceptable bomber destroyer) offered by the Me262 would have been lost to the F80 but as we're talking about a potential combat somewhere in the fall of 1945 then we can't project for one side in the conflict without doing the same for the other, at the risk of skewing the argument unrealistically.

It might be wise to remember that the Me262 wasn't the only iron that the Luftwaffe had in its fire; by fall of that year it may well have been relying on something else - the Focke-Wulf Ta183 anybody? Difficult to know for certain but it isn't hard to visualise it keeping the F80 squadrons tied up whilst the Me262 returned to its duties running at the bomber streams.

 

[FLYBOYJ]

The F86 wasn't as fast as the MiG-15, it wasn't as heavily armed and couldn't climb anywhere near as rapidly; three key attributes in air combat. Despite this, the kill ratio of F86:MiG-15 was about 1:13 if you included MiG pilots of all nationalities involved (Chinese, Korean and Russian).

New research has revealed that the actual kill ratio was more like 6 to 1 and maybe 2 to 1 aganst Soviet Units. In either case the F-86 still had the upper hand on the MiG-15.

 

[Soren]

In real life it goes like this. The P-80, is likely to be faster,more agile in a dogfight but the 262 have far superior firepower and better pilots. In realistic air warfare the aircrafts scores an equal due to better luthwaffe pilots and better guns

In real life everything you have said (except the part about firepower), is incorrect.

The Me-262 is faster, accelerates quicker, climbs better turns better than the P-80. The P-80 likely has a higher roll rate though.

The P-80A's sent to the ETO only achieved roughly a 795 km/h top speed, it wasn't until after the war that performance was boosted to over 800 km/h.

And as for pilots, the LuftWaffe didn't possess better pilots than the USAAF, infact by late 44 45 the USAAF pilots were in general much better trained.

 

[Timppa]

From another forum:
"Comparison testing at Wright Field showed that the P-80A was superior to the Me 262 in every performance category except dive acceleration. In a sustained dive, the 262 pulled away slightly initially. However, it entered full compressibility at Mach 0.84 and continued diving would result in the 262 nosing over through vertical and suffering a sudden catastrophic break-up. On the other hand, the P-80A pilot could simply pop his speed brake...."

 

[Soren]

Hehe, testing at Wright Field showed the Me-262 to be faster, climb faster accelerate faster than the P-80A. So who'ever wrote that on the other forum didn't have a clue what he was talking about.

From the Wright Field Report:
"Despite a difference in gross weight of nearly 2,000 lb (907 kg), the Me 262 was superior to the P-80 in acceleration, speed and approximately the same in climb performance. The Me 262 apparently has a higher critical Mach number, from a drag standpoint, than any current Army Air Force fighter."

 

[Timppa]

Hehe, testing at Wright Field showed the Me-262 to be faster, climb faster accelerate faster than the P-80A. So who'ever wrote that on the other forum didn't have a clue what he was talking about..

You have the original report or link to it ?

 

[delcyros]

The speed numbers seem to be representative for a single test. Judging from the mass test of 125 production Me-262A1 carried out in late 1944 the corresponding average speed at the given altitudes appears to be:

Sea level: 521 mp/h ( P-80´s best altitude, Me-262A beeing significantly slower here)
15.000 ft.: 537 mp/h (slightly slower than the P-80 here)
20.000ft.: 543 mp/h (best altitude for the Me-262, slightly faster here than the P-80)
33.000 ft.: 518 mp/h (slightly faster than the P-80, here)
40.000 ft. altitude is barely in within service ceiling of the Me-262A at a gross weight of in between 6000 Kg (=service ceiling 39.222 ft.) and 5000 Kg(= service ceiling 42.700 ft.). Depending on the load and state of the airplane it would do in between 440 and 465 mp/h at 40.000 ft.

I know that at least two, but probably more like three comparisons were made between Me-262A and P-80. One of them is versus the less able XP-80, which didn´t climbed as well and was slower, too.

 

[Colin1]

The speed numbers seem to be representative for a single test. Judging from the mass test of 125 production Me-262A1 carried out in late 1944 the corresponding average speed at the given altitudes appears to be:

Sea level: 521 mp/h ( P-80´s best altitude, Me-262A beeing significantly slower here)
15.000 ft.: 537 mp/h (slightly slower than the P-80 here)
20.000ft.: 543 mp/h (best altitude for the Me-262, slightly faster here than the P-80)
33.000 ft.: 518 mp/h (slightly faster than the P-80, here)
40.000 ft. altitude is barely in within service ceiling of the Me-262A at a gross weight of in between 6000 Kg (=service ceiling 39.222 ft.) and 5000 Kg(= service ceiling 42.700 ft.). Depending on the load and state of the airplane it would do in between 440 and 465 mp/h at 40.000 ft.

Judging by that
I would say that one of the two key combat advantages of the Me262

i. enormous hitting power
ii. considerable speed margin

is lost (considerable speed margin) with advantage varying depending on what altitude the two planes met; this was generally the pattern of things when prop job met prop job and the guy with the slight disadvantage mostly worked out a strategy to nullify the threat.
I don't how much faster 'slightly faster' is between 20,000 and 33,000ft but it doesn't sound like a considerable speed margin any more, the advantage offered there by the Me262 sounds like it would have been lost, the P80 probably in with a good chance of making an interception before the Me262 pulled away.