Incident Overview
During final approach to runway 13R, the captain received an unsafe nose landing gear indication on the multi-function display unit (MFDU). The captain abandoned the approach and recycled the gear per procedures, which did not resolve the issue. The aircraft landed safely, rolled out, and stopped on the runway. No evacuation was initiated.
Maintenance Response
A maintenance crew met the aircraft on the runway and placed locking pins in the nose landing gear. Multiple simultaneous communications occurred between the maintenance crew, a maintenance supervisor, a maintenance crew chief, and the flight crew. The flight crew asked maintenance personnel whether it was necessary to strap the gear. The supervisor searched the maintenance manuals and found no reference to strapping the gear and informed the crew that strapping was not necessary before towing.
Conflicting Instructions and Attempted Tow
Review of the maintenance manual revealed numerous warnings about towing the aircraft with an unsafe nose landing gear indication. Meanwhile, a maintenance crew chief informed the maintenance personnel that strapping the gear was required, but no strap was available at the airport. Despite a placard on the nose landing gear door indicating the strap requirement, the maintenance crew attempted to tow the aircraft without strapping the nose landing gear. The nose landing gear subsequently collapsed, and the nose of the aircraft came to rest on the towbar. Passengers were deplaned and transported to the terminal by bus.
Examination
Examination of the nose landing gear did not reveal the reason why the down-lock plunger engaged when the nose landing gear was extended.