Has anyone ever encountered the following bawdy piece of WWI doggerel?

Vive le cast iron steel the pilot's best friend
For who would have his cock and balls shot free
So that he could no proper part of England be
No progeny and wealth acquire
Some Fokker having blasted his desire.
Come celebrate with me the thin steel sheet
Where languidly we park our meat
Thus shielding England's tools and seed
Against our country's future need.

It pops up in a Hemingway manuscript where the character is a former WWI pilot, but I haven't been able to track down the source. If anyone could help it would be much appreciated!