What happened
On January 8, 2007, an ATR 42-500, registration OH-ATB, operated by Finncomm Airlines, experienced a significant flight path deviation during its departure from Helsinki-Vantaa Airport. The aircraft was performing a scheduled flight to Seinäjoki. Following takeoff from runway 22R, the aircraft began a sharp left turn, deviating from the assigned departure route and drifting into the takeoff and climb-out sector of the adjacent runway, 22L.
During the initial climb, the aircraft's bank angle reached approximately 35 degrees, and the nose pitch increased to over 19 degrees. The aircraft remained unmonitored for approximately 28 seconds. The deviation was eventually corrected by the captain, who took manual control to level the wings and initiate a right turn. The aircraft eventually stabilized and resumed the correct flight path after the autopilot was engaged.
The investigation
The investigation examined the crew's actions, the aircraft's technical status, and the operational environment. Investigators found no technical malfunctions with the aircraft. The investigation focused on the crew's failure to follow established operating procedures, specifically regarding Flight Management System (FMS) programming and cockpit monitoring.
Key elements examined included the crew's recent rest period, which was limited to approximately four hours following a flight from Pori, and the reduced time available for pre-flight preparations due to a late aircraft swap. The investigation also reviewed the airline's operational manuals (OM-A and OM-B) regarding flight deck duties and the responsibilities of the Pilot Flying (PF) and Pilot Monitoring (PM).