I grew up believing that Lancasters carried bombs and B.17s carried crew !
And I grew up with the song which included (to the tune of Glory Glory) the lines:
"The yanks were flying Fortresses at forty fousand feet (x 3)
With loads of ammunition and a teeny weeny bomb."
AND
"The RAF were flying Lancasters at zero zero feet (x 3)
With no ammunition and a f***in' great bomb!"