What was found
DURING RETURN FLIGHT FROM A RETARDANT DROP MISSION, THE MAIN HYD SYSTEM ACCUMULATOR AIR LINE RUPTURED, RESULTING IN LOSS OF MAIN HYD SYSTEM PRESSURE INDICATION IN THE COCKPIT. THE HYD SYSTEM PRESSURE REMAINED AT NORMAL LEVELS WITH NO LOSS OF CONTROL OR SYS ACTUATION. THE FLIGHT CREW COMPLETED THEIR CHECKLISTS AND LANDED NORMALLY. AIRPORT EMERGENCY VEHICLES WERE PRESENT FOR LANDING WITH NO OTHER ACTION TAKEN.