Incident Overview
A flight crew experienced a hydraulic system failure when a left main gear door-up line ruptured during landing gear retraction. The line had chafed against the auxiliary power unit (APU). In response, the captain ordered the dumping of 30,000 pounds of fuel, followed by an attempt to manually extend the landing gear.
Manual Extension Attempt
The flight engineer (FE) was unable to manually extend the right main landing gear. The captain instructed the FE to observe the gear position through view ports in the cabin, but the FE could not locate the view ports and returned to the cockpit. The captain then ordered fuel to be dumped to a minimum level, after which the aircraft landed with the right main gear retracted.
Post-Landing Inspection
After landing, when the aircraft was raised, maintenance personnel found the right main landing gear stowed normally on the uplock. The gear was subsequently extended using normal manual extension procedures. No evidence of malfunction of the right main gear was found.
Operational Details
It was noted that the right main gear extends by cranking in the opposite direction from the left main and nose gear. The flight engineer had qualified as a flight engineer on November 3, 1991, and had accumulated 200 flight hours in that role at the time of the incident.