Mail Call is on at 6 every weekday on Forces TV. Available on Sky 264, Virgin 277 & Freesat 165
Mail Call discovers the forgotten heroes of Pearl Harbour, the military divers who went to work the day after the historic attack and raised the entire fleet from the bottom of the ocean bar a single ship.
The USS Arizona, too badly damaged to be raised by the divers is now part of the USS Arizona Memorial.
The diving helmet used by the navy divers was the Mark V. It was in use for 69 years from 1916 to 1984. It was around 25kg and bolted to a durable rubberised canvas suit to protect the divers from all sorts of threats including the cold, contamination and dangerous underwater environments.
The modern military divers are spread out across a variety of roles. They range from underwater demolition teams, engineer divers and special operations.
For more underwater military matters, check out how the military are using dolphins or why Royal Engineers are starting to go down into the depths