Lao_Che said:
The joke would be he learned to fly during the start of Temple of Doom, I believe.
He does take some lessons during IJ and the White Witch in 1930 though.
I was about to post the same thing. In fact I would have thought that bone of contention would have warranted a thread. In terms of the OP's question though, Indy could have easily gotten a lesson or two between '35 and '38. In fact, if you think about it, was Indy going to fly the Flying Wing in Raiders with the Ark on it, or did he just think he could steal the Ark back and get away with it (the way he did in the end)? If it was the former, then perhaps Indy might have gotten flying lessons between '35 and '36, but then, of course, Indy was just making it up as he goes.
But yeah... Indy couldn't really have done that much as it was fuel was being dumped anyway, even if he was having amnesia about his flight experience in 1930.