What was found
(CAN) AIRCRAFT ON FIREFIGHTING. AFTER FIRST DROP, THE PANEL INDICATED AN ERROR CODE. RESTART IN CONSIDERATION ALTHOUGH NOT RECOMMENDED BECAUSE OF IMPORTANCE OF FIRE. ON 46TH DROP, THE CREW HEARD THE SOUND OF THE DOOR OPENING, BUT ALL LIGHTS DID NOT CHANGE AND NO ERROR CODE. IN SPITE OF CREW ATTEMPTS, THEY COULD NOT CHANGE INDICATIONS. EMERGENCY PROCEDURES CARRIED OUT. MISSION ABORTED. COULD NOT DUPLICATE. PART REPLACED.