I have memories of my father singing the Lancaster v Fortress song. He was an air gunner in Bomber Command, including Pathfinders. He recalled singing the RAF version over the airwaves to their American colleagues, to irritate them. The only lyrics that I can recall are;
"We were flying Flying Fortresses at Forty Farzend feet, (x3)
But We've only got a teeny, weeny bomb.
We've got bags of ammunition and a hell of lot of guns, (x3)
But we've only got a teeny, weeny bomb."

There were some other verses, which I didn't have the foresight to commit to memory.