You're in the Navy Now

When Cmdr. Tom Reynolds (John McIntire) tries to select a navy officer capable of leading an experimental submarine with a steam engine, the only candidate he can find is reservist Lt. Harkness (Gary Cooper). Harkness tries to lead his crew to successful trials of the ship, but every effort proves to be a debacle. With his men becoming discouraged and the ship now a laughingstock, Harkness must find a way to make the ship function before Rear Adm. Tennant (Ray Collins) comes calling.