Link seems to have an issue but other players noted the altitude in the thread.
http://bbs.hitechcreations.com/smf/index.php/topic,311094.0.html
Guess I will start filming more often when I see this for the disputers. 
Too bad the film isn't available anymore

And yes, roll the film. But by looking at your stats it seems you aren't encountering B-29s very often at all...

By the way, i just tried to get an empty B-29 to 40k. Took off without bombs and at 25% fuel from a 30k base, set some upward wind to get to 36k faster and save fuel. Then I disabled the wind and continued to climb...

Shortly before I ran out of fuel I wasn't at 39k yet and the rate of climb was at 20fpm...
Sorry but B-29s flying regularly at 40k+ is just a fantasy. 30k+? Yes, absolutely. I have killed more than 300 of them, but for sure about the half (mabye even more) was over 30k, but none came ever close to being at 40k.