I've got a P-51 in my back pocket...

[gjs238]

...Or so replied James H. "Dutch" Kindelberger to Sir Henry Self when the latter asked if NAA could manufacture the Tomahawk under license from Curtiss. (I'm paraphrasing of course.)

How long was Dutch/NAA sitting on the P-51?
What if Self (or anyone else for that matter) had made the request 3 months earlier? 6 months earlier? Etc.

 

[drgondog]

NAA started actual design work when they got the contract from the British. There was no propsed design prior to the contract on April 24, 1940 and the 120 day limitation in the contracts was the estimated time for NAA to tool up to produce P-40s.

 

[Shortround6]

I think that every designer worth anything at all had at least a few doodles on paper about a fighter "design". Which is a far cry from a properly prepared design estimate with weights and preliminary stress calculations and so on. Where on the spectrum North American fell I have no idea but I doubt the full plans for the Mustang were sitting in drawers under drafting tables just waiting for a customer to show up
Many of these 'sketches' were probably updated from time to time as new ideas, techniques came to the attention of the designers. For instance the wing section the Mustang used was pretty new.

 

[tomo pauk]

The layout of the wing structure was one of great things about Mustang, even if we put a laminar-flow shape aside for a moment. Two-spar design that allowed for a hefty fuel load, plenty of space for guns ammo, with space for U/C, all within modest dimensions.
Comparing it with P-40, or P-47 wing structure, those two come out as a fairly restricting re. useful internal volume.

 

[Shortround6]

It just wasn't the two spar set up. it was were the maximum thickness was in relation to the cord and over how much of the cord the a certain minimum thickness extended. The more conventional air foils had a maximum thickness at about 30-35% of cord. The Mustang had it's max thickness at about 40% of cord. The rear 70% of the conventional airfoil tapered to the trailing edge meaning that the rear part of the wing, even forward of the ailerons and flaps didn't have a lot of thickness/volume. the Mustang used a much more rapid taper but because of it's greater thickness over more of the cord in had more internal volume than a conventional air foil wing of the same size (area and thickness) would have. I hope I have explained that right.

SEE: http://www.dreesecode.com/primer/p5_f002.jpg

 

[gjs238]

Gotta remember all this next time a P-51 vs whatever comes up.

 

[barney]

The wings were bolted to each other and then the fuselage was lowered onto the wing assembly. This allowed the wing tanks to extend almost to the center line. The wing tank fuel gauges were in the cockpit floor. With full fuel and 110 gallon drop tanks the aircraft had a capacity of 489 gallons.