'The Bravest Man' about Richard O'Kane and the Tang, page 140, "The all-day dives, then considered doctrine, were a severe strain on Argonaunt's equipment, with high humidity contributing to small fires that broke out in electrical equipment." (my comment:!!!!!!!!!!!!!
!!!!!!!!!!!!!!)
Then later in the book where it talks about several subs that were heavily damaged by big storms the main problem began when huge wave water flooded the control rooms of the subs setting of fires because of the salt water.
SO my point is: was German equipment better sealed. Hopefully someone who has studied this subject should know. Perhaps I need to contact uboat.net....