Why does it take so many men to staff the submarine?

The first thing to remember is that three full shifts were needed to operate the boat all day and night at sea.

On the surface at sea, there were a number of jobs to do and there would be one person awake in each compartment to monitor the space for problems or danger. For example, on the surface there would have been:

1. The officer of the deck with three or four lookouts on the bridge.
2. A helmsman and quartermaster (navigation) along with the sonar and radar operators in the conning tower.
3. The Chief of the Watch plus an IC electrician and a messenger in the control room.
4. A radar operator for the air search and IFF equipment.
5. A radioman on watch in the radio room.
6. Two electrician mates in maneuvering.
7. A motor machinist mate (engineman) and an oiler in each engine room.
8. Normally there would have been a cook in the crew’s mess. There would often have been a mess cook there too.
9. A steward mate in the forward battery.
10. A torpedoman on watch in each torpedo room.
11. There are other duties, such as an electrician monitoring the battery, particularly during a charge.
12. A gunner’s mate to maintain the guns

This was a total of about 24 per shift, and there were three shifts.

When submerged, the duties for some of these men would change. For example, the officer of the deck (OOD) would become the diving officer and there would be a new OOD in the conning tower. The oilers in the engine rooms would man the trim manifold and air manifold in the control room. The lookouts would man the bow and stern planes. In total they needed about the same number of men when submerged as on the surface.

They also needed to have additional personnel on board to allow for trainees, injuries and illness. Gun crews also needed to be staffed during battle stations. In addition to these functions, there were the captain, the executive officer, the yeoman and pharmacist mate who may not have been on the watch list. The yeoman and the pharmacist mate might have stood some watches as their primary duties permitted.