NTSB Factual Report

On March 30, 2011, about 1946 eastern daylight time, a Bombardier Inc. CL-600-2B19, N8505Q, operated by Pinnacle Airlines as flight 4067, sustained no damaged when its wheel well bin was found missing after the flight which landed at the Detroit Metropolitan Wayne County Airport (DTW), near Detroit, Michigan. Visual meteorological conditions prevailed at the time of the incident. The 14 Code of Federal Regulations Part 121 scheduled domestic passenger flight was operating on an activated instrument flight rules flight plan. The captain, first officer, flight attendant, and 24 passengers were uninjured during the incident. The bin has not been located and no injuries have been reported by persons on the ground. The flight originated from the Theodore Francis Green State Airport, near Providence, Rhode Island, about 1823.

The operator reported that the flight crew received an engine indication and crew alerting system main landing gear overheat fail message as the landing gear was being retracted. The flight crew performed the quick reference handbook procedures and the message persisted. During the remainder of the flight, the message came on every 15 to 20 seconds and then extinguished. The message did not stay on for more than about five seconds. The flight crew contacted maintenance control and were advised that the flight could continue to DTW since the message was intermittent. On landing at DTW the flight crew noted a rise in the left side temperature indicated on the brake temperature monitoring system.

During the troubleshooting of the cause of the main landing gear overheat fail message, maintenance personnel in DTW discovered that the right wheel well bin, P/N 601R31039-162, had departed the aircraft. The wheel well bin incorporated a temperature sensor.

Federal Aviation Administration inspectors examined the airplane and main landing gear (MLG) wheel wells. The MLG wheel well bin is attached to the fuselage with 11 fasteners. The inspectors took pictures that revealed that three of the MLG wheel well bin’s fasteners were in place and those fasteners had torn sections of wheel well retained under their heads.

According to the operator, the MLG wheel bin is removed to facilitate scheduled maintenance at 100-hour intervals. The last maintenance that involved removal and installation of the wheel well bin was repair of a flap discrepancy on March 24, 2011. Subsequent to release from maintenance on March 24, 2011, the airplane completed 29 flights without incident. At the completion of the incident flight the airplane had 68.5 hours remaining until the next scheduled inspection that required the removal of the MLG wheel bin.

Subsequent to the incident, the operator published a warning in their airplane maintenance manual fuselage aerodynamic faring section. The warning stated:

Do not use electric, battery or pneumatic powered screw guns to secure

MLG wheel bins. Doing so could cause damage to the fasteners and could

cause departure from the aircraft.

NTSB Probable Cause

The mechanic's incomplete securing of all the wheel well bin's fasteners, which resulted in separation of the bin from the airplane.