Accident Details
The flight was conducted as a Part 135 six-month proficiency check for the pilot occupying the left seat. Both pilots were check airmen for the commuter air carrier. The aircraft departed at 2343 following the cessation of the company's revenue operations. The cockpit voice recorder captured the pilots' conversation, which included discussion of aerobatics. The left-seat pilot began describing the performance of a prohibited maneuver, reportedly a barrel roll. The recording ended before the description was completed.
Impact and Evidence
The airplane impacted the ground in a nose-level attitude with the left wing slightly down. Investigators found evidence that the maneuver was performed at an altitude insufficient to assure recovery of the airplane. A filled-out grade sheet for the flight being flown was discovered in the check airman's mailbox.
Fatalities
Both pilots were killed in the accident.
Probable Cause
The official probable cause statement attributed the accident to the deliberate disregard for federal aviation regulations, GP Express procedures, and prudent concern for safety by the two pilots in their decision to execute an aerobatic maneuver during a scheduled check ride flight. Additionally, the failure of GP Express management to establish and maintain a commitment to instill professionalism in their pilots consistent with the highest levels of safety necessary for an airline operating scheduled passenger service was cited.