Here's the answer to my trivia question:
Our Hueys had ceramic/composite armored seats. These seats weighed 150 pounds each, and protected pilot and copilot from .30 calibre rifle fire approaching from the rear, beneath, and sides of the aircraft.
I also wore what was called a "ballistic" helmet, which was supposed to provide some protection for my noggin.
But we were unprotected from anything fired at us from the front or from above.
Before climbing into the aircraft, I would grab my gun belt and shift it 90 degrees, so the .38 was strategically located to provide a little protection for what I considered a pretty important area at the front of my body!
I never heard of an incident where the pistol actually helped deflect a bullet, therefore insuring a pilot was able to later father a family......but to me, feeling the weight of the revolver there during the flight was reassuring.
I was glad to take comfort anywhere I could find it!