And the dog is the reason no one in the U.S. has seen this movie on television in something like 30 years—a product of the time when the English still made their own films without reference to colonial shibboleths.
I understand a remake is in the works...presumably properly sanitised for American audiences.
The bomb was a great idea, but it only worked if you dropped it from a very low altitude. The problem: at night, it was impossible to safely fly low over dark water.
This was in the days before radar altimeters and terrain-following autopilots. They came up with an ingenious solution: two lights on the bomber (either at either end of the fuselage or either wingtip -- I can't remember).
The lights were mounted at precise converging angles, shining down onto the water. When the beams converged on the water at exactly the same spot, the bomber was at the correct altitude.