Incident Details
On October 18, 2010, at approximately 1425 mountain standard time, a Bombardier, Inc., CL-600-2B19, registration N938SW, operated by SkyWest Airlines as United Express flight 6522, arrived at Phoenix Sky Harbor International Airport (PHX) in Phoenix, Arizona. The flight was a scheduled domestic passenger service under 14 Code of Federal Regulations Part 121, originating from Los Angeles International Airport (LAX) at about 1241 Pacific daylight time. Visual meteorological conditions prevailed, and an instrument flight rules flight plan had been filed.
Sequence of Events
The captain reported to a National Transportation Safety Board (NTSB) investigator that the main passenger cabin door's (MCD) power assist motor was inoperative when the flight was dispatched from LAX. He stated that he had been authorized to operate the aircraft to PHX with the MCD's deferred maintenance status, following SkyWest's minimum equipment list (MEL) procedures. Approaching PHX, he advised his company that ground personnel assistance would be required to open the door.
After parking at the gate, a United Airlines employee marshaled the aircraft and attempted to open the MCD from the outside but could not. A captain waiting on the jet bridge to operate the aircraft on its next flight also failed to open the door. The incident captain then exited the cockpit and tried pushing the door while personnel outside pulled, and while he lifted the handle from inside. These attempts were unsuccessful. He returned to the cockpit and made a public address announcement informing passengers of a delay due to technical problems with the door.
Subsequently, the captain opened the galley service door on the opposite side of the aircraft to communicate with ramp personnel. He planned to have them stow the door handle from outside while he attempted to open the MCD from inside. Following this plan, he pushed his shoulder against the door with exerted force. The door opened beyond its normal limits and rotated downward until it impacted the tarmac. The elapsed time from arrival at the gate to MCD opening was about 10 minutes.
Outcome
The MCD sustained damage to its supporting wheel assembly and power assist motor cable. The cable was found stuck inside the door. There were no injuries to the 2 airline transport pilots, 1 flight attendant, or the 50 passengers. The aircraft experienced minor damage limited to the main cabin door.