Me-262 Design Analysis

[MIflyer]

Time for a new WW2 design analysis. Here is one on the Me-262. First part is the airframe.

 

[MIflyer]

It appears I'll have to post the engine section separately..

 

[GregP]

Thanks, MIflyer!

 

[ChrisMcD]

Great posting.

I always wondered why the 262's bomb pylons were called "Viking ships" - now I know thanks to file 3

 

[MIflyer]

By the way, I have a number of books in my library on the Me-262 but I recently bought David Baker's book and it's the best overall. It would have been even better had he included this material.

 

[Koopernic]

By the way, I have a number of books in my library on the Me-262 but I recently bought David Baker's book and it's the best overall. It would have been even better had he included this material.

Does the David Baker book say anything on the aileron tabs?

Boyne says the aileron tabs were spring servo tabs to assist the pilots joystick input. Your excellent article says they were probably designed as servo tabs but they had not been rigged up to the joystick so they were ground adjustable trim tabs only.

Germans refered to servo spring tabs as fletner tabs. Several German aircraft used servo spring tabs Fw 187, Ar 234, He 177,Ju 290. Do 335 used hydraulic boost apparently.

Spring tabs are notoriously difficult to setup due to flutter and force feel issues but once perfected they work well eg B707 or B36.

 

[MIflyer]

David Baker's book does not seem to say anything about that. In Capt Brown's book, "Wings of the Luftwaffe" (GREAT BOOK!!!) there is a cutaway drawing that shows Fletner tabs on the ailerons.

 

[fshort]

HI MIflyer:

Thanks for posting these!

Regards,
James

 

[MIflyer]

Here is an early concept for what became the P-59. Obviously basically a P-39 with jet engines in the wings.

 

[tomo pauk]

Excellent. Too bad it was not pursued instead of the XP-59.

 

[MIflyer]

I tend to agree. A P-63 based version would have been even better. If the engines had been located in that manner rather than as the P-59 firing the guns would likely have been less of a problem. Directional stability was a problem with the P-59, Meteor, and Me-262 and I doubt the P-39 design would have helped that, but I don't know.

But given the available engines I doubt it would ave been a viable operational aircraft anyway.

 

[GregP]

Directional stability was an issue due to lack of information. When Larry Bell was asked to come up with an airframe, they didn't tell him how big the engines were, how much air they needed, or how much thrust they made.

They gave him a big block of wood and said, "they won't be any bigger than this block of wood."

So, the intake are way oversize for the needs of the engine and a lot of air spills out front as it is NOT used by the engine. I'm afraid that no matter WHAT airframe were selected, the lack of information would have forced the same issues on it. We have had former Bell employees come to the museum and talk on the project, and the main issue was ENGINE. Had they known more, they could have done better, but they did what they could with what they had at the time.

 

[Koopernic]

Directional stability was an issue due to lack of information. When Larry Bell was asked to come up with an airframe, they didn't tell him how big the engines were, how much air they needed, or how much thrust they made.

They gave him a big block of wood and said, "they won't be any bigger than this block of wood."

So, the intake are way oversize for the needs of the engine and a lot of air spills out front as it is NOT used by the engine. I'm afraid that no matter WHAT airframe were selected, the lack of information would have forced the same issues on it. We have had former Bell employees come to the museum and talk on the project, and the main issue was ENGINE. Had they known more, they could have done better, but they did what they could with what they had at the time.

The XP-59 was badly done in many ways, not necessarily faults of Bell. Over at the NACA the man who gave the world the NACA 4 and 5 digit airfoils as well as developing the Laminar Flow Airfoils used in the P-51 called "Eastman Jacobs" was developing a 600 mph aircraft called "Jakes Jeep" as a step to breaking the sound barrier. It eventually became the X1. It used the excellent transonic properties of the so called 'laminar" foils. "Jakes Jeep" used a motor jet. A Turbocharged PW R-1535 twin wasp drove a compressor the air from which was then heated by burning fuel and also the heat from the engine. Unlike the Caproni Campini N.1 Jake's Jeep did not have a poor supercharger. Most importantly Jakes Jeeep engine also had demonstrated efficient combustion.

(Caproni Campini N.1 unfortunately almost discredited the credible motor jet concept by going of half cocked)



Apparently the XP-59 did have the new airfoils: In-compete Usage lists them as
Bell 27 P-59 Aircomet NACA 66-014 NACA 66-212
Apparently the wings were simply too big or thick.

Him and the NACA being kept out of the loop broke Eastman Jacobs heart and he retired early in 1944.

 

[MIflyer]

Too bad Jacobs didn't stay in. NACA practically tried to sabotage the X-1, insisting on a jet powered aircraft rather than rocket powered. The USAAF insisted on rocket power and that was a good thing; the X-1 would have not been successful.

NACA's recommendations did result in the USN building the D558-1, which was already being surpassed by operational jet fighters by the time it rolled out.

 

[JSConnolly]

Time for a new WW2 design analysis. Here is one on the Me-262. First part is the airframe.

Now THESE are some SUPER Useful pics! I am doing "Working Landing Gear" and control surfaces on a 1/32. ME 262 and these are GREAT Sources for me!

Thanks for posting!

Joe

 

[MIflyer]

Apparently the XP-59 did have the new airfoils:

Same as the P-39? First concept....

 

[drgondog]

Eastman Jacobs led the development of the NACA 45-125 Laminar Flow airfoil with 20% T/C. Ed Horkey led NAA's developent of the NAA/NACA 45-100 16% T/C Low Drag/High Speed. The design methodolgies of Complex Transformations (Kuta-Jukowski and Theodorsen) were essentially the same to conceptualize the pressure distribution to generate the airfoil co-ordinates.....coupled with Pitching Moment, etc desirables.

 

[Zipper730]

drgondog

While Koopernic has been banned, I'm curious if the following were correct

"Jakes Jeep" used a motor jet. A Turbocharged PW R-1535 twin wasp drove a compressor the air from which was then heated by burning fuel and also the heat from the engine. Unlike the Caproni Campini N.1 Jake's Jeep did not have a poor supercharger. Most importantly Jakes Jeeep engine also had demonstrated efficient combustion.

What I'm wondering is how the engine's efficiency compared to gas-turbines. I do remember that NACA had really hitched everything to motorjets.

Him and the NACA being kept out of the loop broke Eastman Jacobs heart and he retired early in 1944.

Is that actually why he actually quit? I know he eventually ran a diner.

Same as the P-39? First concept....

The wings were still too thick, but it looked a lot like a mix between the P-39 and the Gloster Meteor

 

[GTX]

New book coming that is relevant here:

MESSERSCHMITT ME 262: DEVELOPMENT AND POLITICS | Mortons Books

Book - Messerschmitt Me 262: Development and Politics

www.mortonsbooks.co.uk

 

[MIflyer]

David Baker wrote the best book I know of that goes into the ME-262 development and politics.

I find it interesting that both Heinkel and Lockheed both wanted to get into design and production not only of jet aircraft but jet engines as well, and both were told "NO!" by their respective governments. Heinkel eventually bought the Hirth company, just so they could say they were an engine company, too.