Thanks for the responses.
Olham, Wels,
I tried the full power vertical dive from 15,000 ft in an Albotross DIII. Speed was in excess of 250mph when I pulled out at about 1,000 ft. The wings stayed on.
Uncleal,
I've tried the full powere vertical dive from 15,000 ft with several birds including the SE5a. In every case I was able to pull out of the dive between 1,000 and 2,000 feet without any structural failure.
I'm puzzeled that the observations by the three of you are different.
I'll post the poll when and if I figure out how. I may try a few more airplanes first.