How would the Allies have dealt with large numbers of ME 262s?

[Glider]

At the end of the day had the 262 been available in large numbers then the allies would have put a much higher priority on the development of the Vampire, Meteor and P80.
The Meteor Mk III had some built in restrictions and was essentially a stop gap until the Mk IV was ready. With a higher priority the Mk IV would probably have come in earlier and the longer nacells for the Mk III which significantly improved performance would also have arrived earlier. The Vampire was in production during WW2 but not sent into action but with a higher priority would have been available for front line service.
The country with the most to lose when facing large numbers of german jets is Russia who as far as I am aware didn't have anything available apart from the B1

 

[Erich]

US pilots were given credit for around 100 jets this accounts for all types, no He 162's since they were not engaged. Hess's book needs to be re-written with more first hand accts from both sides.......geez maybe I'll do that myself.

 

[pattern14]

US pilots were given credit for around 100 jets this accounts for all types, no He 162's since they were not engaged. Hess's book needs to be re-written with more first hand accts from both sides.......geez maybe I'll do that myself.

The itemised index at the back lists all the "confirmed" kills, so i'm only passing on what I've read. I'm finding it a bit of a struggle at times, wondering what to believe. The book was written 17 years ago, so it is entirely plausible there has been more accurate info since then. I've read 150 kills for the 262, and I've read 720+ as well. I'm sure the correct figures are out there somewhere......

 

[stona]

The itemised index at the back lists all the "confirmed" kills, so i'm only passing on what I've read. I'm finding it a bit of a struggle at times, wondering what to believe. The book was written 17 years ago, so it is entirely plausible there has been more accurate info since then. I've read 150 kills for the 262, and I've read 720+ as well. I'm sure the correct figures are out there somewhere......

We'll never know for sure exact numbers for "kills" for different types. I don't think 150 jets is unreasonable at all.

There were over 100 Me 262s shot down with known werknummern, which we can match (more or less) between German loss reports and Allied claims. There are others which were certainly shot down but where this is impossible.
The same problem will exist for the other types meaning any author can only make a best estimate.

Cheers
Steve

 

[OldSkeptic]

i always wondered if the lightning could have taken rolls royce engines or griffin engines ... they increased the speed of the p-51 i was wondering if it would have done the same to the p-38 ?

Nope, the problem was it miserable mach limit. Late model P-38's maximum speed was very close to the its mach limit and as such they were limited to only very shallow dives. The 'dive recovery flaps' only added, if used before control was lost, about .2 of a mach to its limit. Beyond that .. all over .. lawn dart time.

There was no point in giving this thing any more power, it was at its aerodynamic limits already.

Did much better low down (and in warmer air) where the mach limits were not so bad and it was slower, but even used as a ground pounder you still had to be very careful about steep dives.

Bit of a shame, great concept but the aerodynamic knowledge of Lockheed at the time was not up to it.

One of the reasons why they went to the P-51, it was the only US plane with comparable mach limits to the German fighters it was against. The P-47 was better than the P-38, but still poor (0.72 from memory, while the Mustang was 0.8 similar to the 109 and 190).

An awful lot of US pilots were last seen in steep dives in their 38s and 47s. The -47 was a little bit more forgiving too in that it was pretty strong and provided the pilot didn't panic and stuff up when control was lost, if they waited until they got into thicker air then you could recover it. Later dive recovery flaps helped that process. But you were still a passenger when that happened.

Unless a 109 or 190 was on your tail, still with control and shot you up of course.

The Mustang was much better aerodynamically (to be fair it was later design) plus it had a benefit in that it would give a pretty clear warning that you were close to the limit by starting to porpoise. That meant, if you knew what you were doing, that you could keep it in the control zone, close to but not over the edge.

 

[swampyankee]

There was a previous post with Bf109 never-exceed speed data: http://www.ww2aircraft.net/forum/flight-test-data/bf-109-dive-rate-19817-6.html#post550872

 

[FLYBOYJ]

Nope, the problem was it miserable mach limit. Late model P-38's maximum speed was very close to the its mach limit and as such they were limited to only very shallow dives. The 'dive recovery flaps' only added, if used before control was lost, about .2 of a mach to its limit. Beyond that .. all over .. lawn dart time.

There was no point in giving this thing any more power, it was at its aerodynamic limits already.

Did much better low down (and in warmer air) where the mach limits were not so bad and it was slower, but even used as a ground pounder you still had to be very careful about steep dives.

Bit of a shame, great concept but the aerodynamic knowledge of Lockheed at the time was not up to it.

One of the reasons why they went to the P-51, it was the only US plane with comparable mach limits to the German fighters it was against. The P-47 was better than the P-38, but still poor (0.72 from memory, while the Mustang was 0.8 similar to the 109 and 190).

An awful lot of US pilots were last seen in steep dives in their 38s and 47s. The -47 was a little bit more forgiving too in that it was pretty strong and provided the pilot didn't panic and stuff up when control was lost, if they waited until they got into thicker air then you could recover it. Later dive recovery flaps helped that process. But you were still a passenger when that happened.

Unless a 109 or 190 was on your tail, still with control and shot you up of course.

The Mustang was much better aerodynamically (to be fair it was later design) plus it had a benefit in that it would give a pretty clear warning that you were close to the limit by starting to porpoise. That meant, if you knew what you were doing, that you could keep it in the control zone, close to but not over the edge.

I think your assessment of the P-38 compressibility problem is a bit overstated – "problem handled" on the "J" and "L" models with the incorporation of dive flaps that assisted in getting out of compressibility. Avoiding compressibility dives was something pilots were taught to deal with and PTO fighter groups and squadrons had little attrition losses due to this phenomena, check operations of 5th AF fighter groups (475th comes to mind). As a matter of fact one of the only well known PTO aces I know of that was killed in a compressibility dive was Ken Sparks (39th FS), so if "An awful lot of US pilots were last seen in steep dives in their 38s and 47s" I'd like to know what those numbers are.

I knew one P-38 ETO drive (Col Mike Alba, 55th FG) and in many ways he felt the later model P-38s were superior to the P-51 (Twin engines, better gun platform). Mike told me that an experienced pilot knew his limitations and knew when to avoid compressibility issues.

The P-51 was IMO the better over-all aircraft of the two, but I think in the end operating cost caused the P-38 to quickly disappear at the end of WW2.

 

[GrauGeist]

Wasn't it Bill Goodson that brought his P-47 back from a compression dive during the bluff that saved his squadron mate?

Warped the sh!t of of his airframe but made it back to England...

 

[parsifal]

We'll never know for sure exact numbers for "kills" for different types. I don't think 150 jets is unreasonable at all.

There were over 100 Me 262s shot down with known werknummern, which we can match (more or less) between German loss reports and Allied claims. There are others which were certainly shot down but where this is impossible.
The same problem will exist for the other types meaning any author can only make a best estimate.

Cheers
Steve

Is it just me, or do the accuracy of Allied claims to German admitted lossed tend to get closer to each other as the war progressed. By this I mean....early in the war allied claims were pretty wild, later in the war they seem (to me) to get closer to the truth. perhaps the squadrons had more resources to cross check and verify the vercity of claims.

Forsyth in his book on RAF ops 1942 (a day by day account for each squdron in NW Europe) estimates the inaccuracy of claims to actual losses at about 3 losses for every 4 claims made. im not sure what he baases that on.....

 

[OldSkeptic]

I think your assessment of the P-38 compressibility problem is a bit overstated – "problem handled" on the "J" and "L" models with the incorporation of dive flaps that assisted in getting out of compressibility. Avoiding compressibility dives was something pilots were taught to deal with and PTO fighter groups and squadrons had little attrition losses due to this phenomena, check operations of 5th AF fighter groups (475th comes to mind). As a matter of fact one of the only well known PTO aces I know of that was killed in a compressibility dive was Ken Sparks (39th FS), so if "An awful lot of US pilots were last seen in steep dives in their 38s and 47s" I'd like to know what those numbers are.

I knew one P-38 ETO drive (Col Mike Alba, 55th FG) and in many ways he felt the later model P-38s were superior to the P-51 (Twin engines, better gun platform). Mike told me that an experienced pilot knew his limitations and knew when to avoid compressibility issues.

The P-51 was IMO the better over-all aircraft of the two, but I think in the end operating cost caused the P-38 to quickly disappear at the end of WW2.

From the P-38 Flight Operating Instructions for the P-38H, P-38J, P-38 L-1 L5 and F-5B Airplanes:

DIVE RECOVERY FLAPS.—P-38L and Later P38J airplanes are provided with dive recovery flaps to improve the dive recovery characteristics of the

As described above, the airplane without these flaps becomes very nose heavy and starts to buffet above placard dive speeds. This condition is caused by a high speed stall and a consequent decrease in lift in the wing producing the nose heavy condition.
The dive recovery flaps which are installed under the wings between the booms and the ailerons, restore the lift to this portion of the wing and thus cause the uncontrollable nose heaviness
to occur at a higher speed.
The flaps also add some drag to the airplane, which in conjunction with the higher allowable dive speed, permits safe dives at a much steeper diving angle.

The dive recovery flaps should be extended before starting the dive or immediately after the dive has started before a buffeting speed has been reached. If the airplane is buffeting before the dive recovery flaps are extended, the buffeting will momentarily increase an d then diminish. With these flaps extended, the nose heaviness is definitely reduced but the diving speed should never be allowed to exceed the placard by more than 15 or 20 mph.

With the dive recovery flaps extended before entering the dive, angles of dive up to 45° may
be safely accomplished.

Without dive recovery extended, the maximum angle for extended dives is 15°.
Diving characteristics are better with power off than with power on.

As can be seen the max allowabe speeds are not much more than a P-51's max level speed.....

 

[GregP]

Funny we dive our P-38 at 90° all the time in aerobatic exhibitions, but not from 25,000 feet. The zoom climb from a high speed airshow pass gets us only about 8,000 to 10,000 feet (when solo without the formation) or so (depending on the plane(s) in the maneuver) before coming back down. Doesn't have any problem with loops, rools or any maneuver ... maybe snaps. I guess it wasn't all that aerobatic:




It is the silver Sea Fury with the BIG engine (R-4360).

 

[stona]

Is it just me, or do the accuracy of Allied claims to German admitted lossed tend to get closer to each other as the war progressed. ....

Off the top of my head, and totally unscientifically, I think they do.

Cheers

Steve

 

[silence]

Rolls-Royce built the Griffon (note tha spelng). I don't really see why that would be necessay; the Lightning was pretty darn good with the turbocharged Allisons.

Here's one person's opinion on the idea:

I don't think we would have seen an increase in performance because
the turbo-allison performed well at altitude when the problems were
fixed. The two stage Merlin might provide some speed increase at the
lowest altitude probably at the cost of some loss at high altitude.

What I think would have happened is that the less bulky Merlin would
have freed a lot of space in the booms that was othewise filled with
exhaust and intake ducting and that might have allowed another 50
gallons of fuel to be carried internally in each boom. (turbo
charger was mounted about 3ft-4ft behined the engine on the upper part
of the boom)

An 'idiosynchrasy' of American turbos was that at US Army insistance,
based on NACA recomendation, the turbo and the engine were seperated
by long straight runs of ducting. Done for reliabillity reasons but
obviously cost space.

There also was a two stage Allison. The Allison V-1710-121 engine
rated at 1,425hp for take-off and 1,100hp at 7620m was a two stage two
speed supercharger used on the P-40Q, which at 422mph matched or even
outperformed any Mk IX/XVI Spitfire in terms of speed and matched the
Me 109G-14AS. This engine sounds less powerfull than the Merlin 60
series but note that the absence of an intercooler probably kept the
weight down to around 600kg as opposed to the 745kg of the Merlin.

So this could have been fitted to the P-38 instead of the turbo
version. The reason it wasn't fitted to the P-51 was that the
arrangment of the gear driven supercharger was about 30cm longer than
the Packard Merlin and just didn't fit easily into the P-51. (The two
stage Merlins themselves must have been bulky due to the intercooler
themselves so so the V-1710-121 or German DB605DCM migh have done
even better.)

The Turbo charged V-1710 wern't known for their maximum power rating
(though they reached a decent 1700hp late in the war) however simple
ratings can be deceiving: the Merlins power vs altitude curve has many
inflexions and flat spots due to gear changes and throttling back of
excess pressure that was only usable in a narrow band and the Allision
clearly maintained power better at high altitude.

Pulling out power from the shaft to power a powerfull two stage
supercharger is clearly going to cost more power than using exhaust
gases to power via a turbo.

However the reduced exhaust backpressure and the greater jet thrust
is going to partially make up for it. The Merlin 66 had 300lbs of Jet
thrust which at 440mph was equal to 260kw-300kW (ie 450hp). I have no
figures but immagine a turbo would have sucked out more than half of
that.

 

[silence]

Funny we dive our P-38 at 90° all the time in aerobatic exhibitions, but not from 25,000 feet. The zoom climb from a high speed airshow pass gets us only about 8,000 to 10,000 feet or so (depending on the plane(s) in the maneuver) before coming back down. Doesn't have any problem with loops, rools or any maneuver ... maybe snaps. I guess it wasn't all that aerobatic:

Maybe it wasn't so bad after all, huh? Seen any other warbirds do better? I've seen Steve Hinton do MORE with it that would shock the "it's unmaneuverable" claimers. He departed early in this act only because he was a new member of the team, the left engine had only 2.5 hours on it, and the Horsemen at the time (Ed Shipley and Dan Freidken) had practiced the last part of the routine and Steve hadn't since the left engine (after overhaul by Joe Yancey) was installed only the day before. They only had time to install it, fly it, and join in what they had practiced earlier before the 8-week overhaul just before the airshow and the short afternoon practice before.

No practice equals no airshow participation in the event for safety. We have had very few incidents as a result. The worst airborne one in the last 10 years has been a fuel tank that departed a plane at 4.5-g's when an auxiliaryfuel tank holding bolt broke over the runway (no other damage or injury ... one reason to STAY over the runway) and one C-47 engine failure on takeoff after the airshow. He flew it around and landed.

That's with 25 - 40 WWII planes at each and every airshow for the last 10+ years plus other civilian and military participation including F-15's, F-16's, F-4's, Alpha Jets, F-86. MiG-15 bis, CT-133, TA-4J, C-17, etc. All in all, pretty darned reliable and pretty darned safe with no rolls on a downline except from altitude after a half-loop or half-cuban-8. All other rolls have to be from an upline. Level knife edge is OK.

Here's another sample. Brian Sanders in Argonaut. Wright R-3350. Notice the rolls are upward except off a half loop maneuver:

Love to see Argonaut do a demo live! The Sanders family have bene flying Sea Furies for 50+ years and know then inside and out. Here's another Sanders family Sea Fury, Dreadnought:

It is the silver Sea Fury with the BIG engine (R-4360).

You have the best hobby EVER!

 

[GregP]

Thanks Silence. It is fun, but I want back into electronic engineering. Did 33 years and want to again.

I think my best hobby ever was my high school girlfriend. She was simply fantastic ... mostly. Discovery was wonderful. Pouting was inevitable. Maybe she wasn't the best ever. Hell, you're right!

Restoration is OK if you can devote an entire Saturday (or any other day, maybe more than 1) to it, but it must be regular or progress simply isn't very fast. Only regular work can make a plane fly again in a reasonable time.

Believe me, when we taxi and/or fly our Bell YP-59A, the video will be right HERE ... assuming I'm here and able. My estimate is March or April 2014. But I could be wrong ... yet again. Depends on the funding availability ONLY. The rest is prety much foregone. Only money will make a difference.

 

[GregP]

Here's how NOT to do it. Biggin Hill.

The pilot had NOT practiced with the aircraft at altitude recently, NOT at low altitude, had NOT flown the plane much, and tried a loop at less than 1/2 power. Note the muted sound of the engine, which is NOT characteristic of an Allison at higher manifold pressures ... a recipe for disaster:


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

Incipient spin if I ever saw one.

Too bad, when the power is up the P-63 is a climbing fool ... as you can see below. He was at 43 inches MAP and the Allison was cleared for 57 inches for Military and 70 inches in the P-63 for WER. 70 inches almost doubles the climb rate from what you see:


View: https://www.youtube.com/watch?v=UiuEpP0HFh0

Sorry, off topic. Will stop and post vids elsewhere. I seem to wander off topic but mean no harm to the thread ... here's something ON topic:


View: https://www.youtube.com/watch?v=PjyIo8uRBDI

 

[OldSkeptic]

Great stuff Greg.

Yes stay under the mach limit (helped by saying low of course) and very maneuverable.
Did well in the MTO and PTO, just high altitude, high speed stuff in the ETO were way outside its comfort zone.

 

[Njaco]

The Kingcobra crash was just brutal. d@mn.................

 

[FLYBOYJ]

As can be seen the max allowabe speeds are not much more than a P-51's max level speed.....

And during maneuvering combat, you're never seeing those speeds unless you need to get out of trouble quickly. Again, this is something that experienced pilots avoided.

BTW, the note from the text says

"With the dive recovery flaps extended before entering the dive, angles of dive up to 45° may be safely accomplished."

It doesn't state that's the limit...