accident-free operation

accident-free flying / mishap-free flying

mishap-free flying / accident-free flying

aircraft accident (flight accident; aircraft mishap)

aircraft accident / flight accident, aircraft mishap

aircraft mishap / flight accident, aircraft accident

flight accident / aircraft accident, aircraft mishap

aircraft accident; flight accident

mishap- / accident-free flying

accident-free

accident-free flight

accident-free flying

knock-free operation

failure-free operation

free-flier operation

trouble-free operation

clandestine operation; covert operation

humanitarian operation; humanitarian relief operation (HUMRO)

PZ operation (pick-up zone operation)

noncombatant evacuation operation (NEO); non-combat evacuation operation

accident report

aircraft accident

nuclear weapons accident

demining accident

demining accident response plan

mine accident

follow-up action on accident reports

post-accident check

accident condition

accident conditions

accident data report

accident data reporting

accident data reporting study group