F4U: Fabric wing surfaces? What were they thinking?

Fabric seems a bit antiquated for a fighter/interceptor design at this time (?)

gjs238 said:

Fabric seems a bit antiquated for a fighter/interceptor design at this time (?)

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Not really. Weight savings, easy access and esay repair.

FLYBOYJ said:

Not really. Weight savings, easy access and esay repair.

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It's interesting that as the aircraft evolved, all-metal wings were introduced on the F4U-5.

The F4U-5 was a post-war variant, and with the higher performance engine, the fabric surfaces deformed and bulged, which slowed the aircraft down, do they went to the metal wings because of that.

Due to the higher horsepower, the fuselage was lengthened by 5 inches (127 mm) and the engine angled down about 2º to provide more stability. Until the dash 5, the outer top wing panels and the control surfaces of the Corsair had been fabric covered. At speed, the fabric tended to deform and slow the aircraft by a few miles per hour. The F4U-5 had all fabric surfaces replaced with sheet duralumin to minimize this problem. Armament was the same as the F4U-4.

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Yep, similar with other types too. For instance, the Spitfire originally had fabric covered ailerons. But, as engine power, and therefore speed, imcreased, these caused 'flutter', due to the exact same thing - bowing and/or sinkage of the fabric. Hence, they were changed to metal covering.
It also needs to be remembered that, at the time many of these aircraft were intially designed, the 'technology' for stressed-skin construction, overall, was still relatively 'simple', and under development. In order to achieve the required smooth surfaces, particularly on airfoil sections, the 'traditional' methods were still used. As techniques, technology and materials improved, changes were implemented accordingly. A good example might be the Hurricane, which started life with wood and fabric covered wings, and progressed to metal, and, of course, the improvements in design, and stress reliability, of flush riveting, as opposed to the 'dome head' or 'mushroom' riveting process of 'earlier' days.
From the time of these designs - Hurricane, Bf109, Spitfire, Corsair etc, to the time of the revolutionary wing design of the P51, was less than 10 years, a remarkable achievement, in a still-young industry, to be able to design, produce, and use, a laminar flow wing.

Another thing they were thinking of is weight. While we tend to think of Aluminium as light the fabric was even lighter. For some reason 9 oz per sq yd sticks in my head but I could be wrong on that.

Some designers were trying to use the metal skin to handle some of the stresses, others weren't quite there yet and had the frame work handle all of the loads and just covered the frame work with the lightest covering they could.

Weren't the P-38, P-39, P-40, P-43 all metal?
And the even older P-35 was all metal.

True but then they weren't Chance Vought aircraft.

Many designers were not eager to abandon what they knew (and what their factories had expereince with, see Hawker Hurricane) to try the 'new' metal skinned aircraft.