cool things with wheels, since 2006
Having flown sailplanes, I think the "smoke thermal" over Tokyo was a violent UP-draft (much like the kind found above large forest fires). The B-29 flying into this huge rising air mass could easily be tossed over and flipped upside down and still GAIN 5000' in elevation in a matter of seconds. Just like an burning ember rising off a campfire. Wow, it must have been one hellofa ride.