‘All we can do for you now’: How Czech sabotage saved a B-17 crew

BTW, there are also confirmed stories of the Jews, the Poles and others who were made to work at explosives doing similiar things to sabotage the Germans.

After losing both of the bomber’s waist gunners, Tondelayo crew members, upon successfully returning to England, discovered 11 unexploded 20 mm shells housed in the bomber’s gas tank. Such placement of explosives would normally spell out certain death for all on board, except for a “highly personal miracle,” Bendiner recalled.
In looking at the shells’ construction, the armorers found no explosives. Instead, the munitions were “clean as a whistle and as harmless,” Bendiner wrote. One shell, however, wasn’t quite empty.
Inside the casing was “a carefully rolled piece of paper” written in Czech, he noted.
“This is all we can do for you now,” the message read.

Little miracles occur in the strangest places.