I read an account of a new RAF bomber crewman who arrived at his base while his new unit was out on a mission. None of them ever came back from that mission (I don't remember whether it was a flight, or a squadron that was lost).
Losses among airmen, especially bomber crews, are unbelievable at this point in the War. The guys who are more involved students say that we are sacrificing bomber crews in order to wipe out the Luftwaffe’s fighter capability in advance of the Normandy invasion.