Lacking any form of navigational equipment whatsoever, the Neger's pilots were instructed to wear watches with compasses in them and peer through the vehicle's bubble dome to gradually steer toward enemy ships. Because of the Neger's unfortunate position slightly below the surface of the water, waves constantly washed over the dome, making it basically impossible to see through.
"You mean they have to be able to see, too? Fritz, you impossible bastard, I'm only one man!"
Upon reaching a target, the pilots had to pull a lever to launch the Neger's lone torpedo, except the release mechanism had a habit of jamming pretty much all the time, thus dragging its surprised pilot into the inevitable explosion with it. Over the course of its short career, the Neger sunk a total of four ships but killed an estimated 80 percent of its pilots.
Though that was still less suicidal than ...