Yes, a vest or something to keep some crucial gear on him would be best. When things are happening that fast, stopping to grab a bag probably isn't in the cards. And your stuff gets 'rearranged' when the aircraft (or car) flips.

"Trapp said the engine sputtered and felt like it was running out of gas, but said there was still three hours worth of fuel in the tank."

When I used to fly with a small-aircraft pilot, he always drained a cup of fuel out of the tank just before every trip. Water is heavier than the fuel, so if there is some condensation or other source of water in it, it settles to the bottom and is drained into the cup. I wouldn't be surprised to hear that this is what happened in this case.

Sue