Complex sentence: The Marine Aerial Navigator insignia is issued to enlisted personnel trained to act as navigators onboard Marine aircraft; the Naval Aviation Observer insignia is issued to flight support personnel; and the Aircrew insignia is issued to enlisted personnel trained to operate equipment onboard airborne aircraft.
Split into simpler sentences: The Marine Aerial Navigator insignia is issued to enlisted personnel trained to act as navigators onboard Marine aircraft. The Aircrew insignia is issued to enlisted personnel trained to operate equipment onboard airborne aircraft.