F4U F6F P-38 P-47 or P-51 Which plane was best by war's end

[FLYBOYJ]

Food for thought; the US military, 60 years ago or today will not put out a "TO" (Technical Order) which is essentially the pilot's manual (and all other flight and maintenance manuals) unless what is in that book matches exactly what the aircraft is advertised to do. The data in the pilot's manual should be the basis of any analysis. If any test reports exist showing higher over-all performance, so be it, but be rest assured, as far as the USAAF was concerned, what was in the pilot's manual is gospel - period!

Perhaps higher performance levels were not issued, but TO's were issued restricting performance to something below the advertised levels. I know there were several such TO's w.r.t. the P-39, for example.

The F4U-4 pilots manual lists 4.9 minutes to 20k (based on 1946 flight tests), where Vought lists 5 minutes to 20K (based on 1944 flight tests). Not sure what's up there???

I think what you're seeing is a phenomena during aircraft manufacturing that could only be labeled as "build of of tolerances," which may cause aircraft to perform differently depending where and when they were manufactured. For example, you many be producing 300 aircraft down an assembly line. Fabricated parts and sub assemblies carry a manufacturing tolerance of say +/- .010. combine this when assembled and then placed into larger sub assemblies, the variances begin. When larger assemblies hit the assembly jigs, the tolerances may now be a lot tighter, thus resulting in rework during major assembly. This may produce additional variances in dimensions through out the airframe assembly process. To further compound this situation, while you're manufacturing these aircraft the assembly tooling wears. By the time you get to the 300th aircraft, that aircraft may be dimensionally in tolerance, but may different in its asymmetry from the first aircraft assembled, while still being in tolerance. This could definitely cause performance variances between aircraft, therefore when the TOs are produced they would normally reflect the most conservative numbers

When I worked at several aircraft manufacturers, I seen this happen quite often. You usually get an aircraft at some point of the manufacturing process that performs better than advertised. As a result of this, aircraft manufacturers have adopted a process called
Geometric Dimensioning and Tolerancing which considers total tolerances of detailed parts and sub assemblies as compared to adjoining parts during the assembly process. This process did not exist during WW2.

 

[wmaxt]

Tolerances do change and affect each aircraft differently. It is also true the T.O. is considered the only facts that apply. It is equaly true that variances in the field make a huge difference in the performance of individual aircraft. Which plane is waxed, which has paint etc.

In '43/'44 Art Heiden flew 300+ combat hours with the same engines and no aborts. This was a time where P-38 engine problems were the highest. An egine issue or Pilot/maintenance issues and what other capabilities were affected?

There is also a story about a "Perfect B-17" that needed NO trim adjustments for the airframe. It wen't through the war (1 1/2 tours I belive), the red cross ferry flights, arial mapping tour, a year of "Geologic Year" studies in both the artic and the antartic and never had an injury or death on board. The aircraft was brought back to the US in the '80s to be restored for a museum. 5 of the original crew met the plane as it landed.

Everything that happens to an aircraft affects its performance. I think this is why the AAF never puts the Max performance figures in it's T.O.s/flight manuals. In practice settings lower than shown in the manuals are often used especialy in formation situations. Performance figures were reduced after the war in some cases too.

wmaxt

 

[evangilder]

You wouldn't happen to know which B-17 that is, would you? I am curious.

 

[FLYBOYJ]

When I worked at Lockheed building P-3s our subcontractor who built the wing dropped a right wing at their factory. It was repaired and shipped to Burbank. During final assy., it was discovered that part of the flap bay was rebuilt outside the assembly jig and this resulted in a slightly wider gap between the right flap and right wing as compared to the left wing and left flap. I was told by our production flight test guys that at max power and at altitude the P-3 would not trim through its vertical axis. Not only did this particular aircraft trim straight, it was about 10 knots faster! The customer who this plane was going to at first was not going to accept it, but changed their minds when they saw the test results! (NS if you're reading this it was the 5th or 6th CP-140 built! ).

 

[Nonskimmer]

(NS if you're reading this it was the 5th or 6th CP-140 built! ).

An interesting bit of trivia that I knew nothing about. Cool!

 

[FLYBOYJ]

(NS if you're reading this it was the 5th or 6th CP-140 built! ).

An interesting bit of trivia that I knew nothing about. Cool!

It might be S/S 140106 or 07.

 

[FLYBOYJ]

Everything that happens to an aircraft affects its performance. wmaxt

I've flown airplanes that were repaired after a major accident. Although repaired correctly, for the most part, they are never the same.

 

[wmaxt]

You wouldn't happen to know which B-17 that is, would you? I am curious.

evan, I don't remember I watched its aquisition, return and delivery pretty closely but it was 1986 or so and I only remember the gist of it now.

I think it was to go to a museum on the East Coast maybe even the Air and Space museum.

wmaxt

 

[Nonskimmer]

It might be S/S 140106 or 07.

I actually know a couple of guys who do a lot of the maintenance on the ones that fly out of CFB Greenwood. I may just pass this on to them.
For all I know that particular aircraft might be out on the west coast, but what the hell. You never know.

 

[FLYBOYJ]

It might be S/S 140106 or 07.

I actually know a couple of guys who do a lot of the maintenance on the ones that fly out of CFB Greenwood. I may just pass this on to them.
For all I know that particular aircraft might be out on the west coast, but what the hell. You never know.

I also know on one CP-140 that Lockheed mislocated a bomb bay bulkhead, causing the bomb bay doors not to fit. A special set were made for that particualr aircraft and the CAF were given an extra set of bomb bay doors just for that aircraft. I would guess that would of been aroud the 10th unit built.

 

[Nonskimmer]

Christ, were they all defects?

 

[FLYBOYJ]

Christ, were they all defects?

Yep, at that time Lockheed was hiring a bunch of "newbees," some of them straight out of trades school or some hired from a Lockheed run training program. In the late 1970s, early 80s there were alot of projects going and many of these newbees were let loose on the P-3 and L1011 subassembly. If they got good in their trade they had the opportunity to transfer to a higher paying job in the "Skunk Works," working on a "classified project." The P-3 fuselages were assembled at Burbank, plant A1 at a dreadful place known as "the docks." It is there where the nose section (Built by Fleet Industries, Ft. Erie Ont.) was joined up with 2 barrel sections, made in Burbank, and a "stubwing" center fuselage made by Canadair. When the "barrel" that involved the bomb bay area on this bird was being built, some brainiac decided to remove the assembly before the thing was fully assembled. Everything shifted and the idiot supervisor though he could continue to assemble the thing outside the tooling. Later his screw-up was discovered, needless to say he was applying at McDonnell Douglas the following week!

Anyway, somewhat back to the subject thread:

Friends, take a look at the P-38 nose section. Turn it upside down and you got a P-80 nose section! I was told this was done on purpose to utilize some of the same P-38 tooling to rapidly develope the P-80!

 

[cheddar cheese]

Wow so it is! I would never have noticed that

 

[FLYBOYJ]

Wow so it is! I would never have noticed that

I believe the wing tips, some of the landing gear components (the landing gear was built by a company called Menasco based a few miles from the Burbank plant), and some of the controls surfaces sub assemblies might also be common.

 

[DerAdlerIstGelandet]

Interesting I never realized that.

 

[FLYBOYJ]

I think other things like rudder pedals and control knobs were also common between the two aircraft.

 

[DerAdlerIstGelandet]

It makes an easier way to build and faster too.

 

[lesofprimus]

I actually knew this info as well.... It makes u wonder why more facilities didnt do this as well.... Woulda saved a hell of alot of $$$.......

 

[Nonskimmer]

I didn't know that part about the nose section. Interesting.

 

[FLYBOYJ]

In todays world, much of the F-117A was taken from other aircraft, primarily from the F-16. No wonder Lockheed eventually bought the F-16 division of General Dynamics!