[Ex Shack]

Hi Dennis
I suspect that the Nav-bomber was a bomb aimer but was qualified as a Navigator and could have flown as such on other missions. Because your a/c was the lead plane it seems reasonable that he was a Senior Nav on the Unit and the mission was conducted, like so many USAAC missions, with the whole formation releasing bombs on the signal of the lead Bomb Aimer, hence a senior,experienced, man in the lead plane who could have taken over from the Bombardier if he thought it necessary to achieve the right accuracy and concentration
Regards
Dick