It would not tear or shred, similar to todays Tyvex, which will not tear or shred until tremendous force is applied.
I assume we can stipuilate that exploding 2cm shells qualify.

When a round penetrates the skin and explodes beneath at a structural piece, the energy tries to escape where it is easiest to do so (like the entry hole) and tears the living s-h-i-t out of it with the help of shrapnel tears throughout the area which explains the many photos I discussed earlier.
One thing is for certain, Vought did not choose to cover the wings with fabric because they thought it would make the plane more vulnerable to enemy fire! Duraluminum was readily available and could easily have been used instead. It was secifically done to make the plane more resistant to damage despite the fact that it was harder to maintain than dural sheeting.
I guess that next you'll argue that since Republic engineers had the same choices in materials, they decided on aluminum because they wanted a plane that would be less resistant to damage.
And I forgot about the wood ailerons. Ever see a piece of wood hit by bullet? Those who have seen bullet impacts through wood will understand. Bullets make much bigger holes in wood than in aluminum.
The rifling in the barrels of all these planes was more often than not badly eroded so that the rounds would start to tumble at longer ranges like beyond 200 yards. (I said
start to tumble. It might take another 300 or 400 yards or more to get completely sideways.) They weren't concerned with pinpoint accuracy so this wasn't a problem. Wood performs horribly compared to aluminum especially if a round strikes off center and, of course, I would argue, fabric does as well.
Back to fabric, once you have a big hole and shrapnell tears in the immediate ares and place very high stress on the fabric from hard manuevering at high speeds it just tears more. We have all seen this phenomenon where planes return with flaps of skin hanging open.
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Flyboy, it sounds like when the F4U-5 had all fabric surfaces replaced with sheet duralumin to minimize those problems, it may have been done to specifically make the plane less resistant to damage (assuming the choice of fabric over aluminum was done to make the surface more resistant to damage) per Lunatic's assessment.
Metal surfaces, although thin are a lot more resilient.
I concur whole heartedly.
