There is no such thing as 28 staff -- or crew or family or whatever. Make it staff members or crew members or relatives (not family members!).

Therefore, one shouldn't say that a plane crash "killed all 59 passengers and crew" or that "140 friends and family attended."

Slightly related: Let "troops" continue to mean a group of soldiers. There's no reason for it to mean individuals. "Soldiers" will suffice for that -- even if some of them belong to the Marines or Air Force.