What Happened on Air Transat Flight 961. Flight Details & Departure • Date: March 6, 2005 • Route: Varadero (Cuba) → Quebec City (Canada) • Aircraft: Airbus A310‑308, registration C‑GPAT, originally delivered to Emirates in 1992 and transferred to Air Transat in 2002. • On Board: 262 passengers and 9 crew members.2. The In‑Flight Incident • Takeoff: Occurred at approximately 02:48 EST, climbing to a cruising altitude of 35,000 ft. • The Event: At around 03:02 am, passengers and crew felt a loud bang followed by severe vibrations. The aircraft entered a Dutch roll, a side-to-side oscillation that threw flight attendants and service carts about. • Crew Response: The autopilot was disengaged, controls taken over manually, and crew initiated a descent to reduce the unstable motion; directional control was regained.3. Decision & Safe Return • Diversion Options: The flight crew initially considered diverting to Fort Lauderdale (Florida), but Air Transat’s operations directed them to return to Varadero — where maintenance facilities were available. • Landing: The aircraft made a safe and uneventful landing back in Varadero at approximately 04:19 am local time.4. Discovery of Damage • Walk-Around Inspection: Once passengers disembarked, the crew performed an external inspection and discovered that the entire rudder had detached from the vertical stabilizer during flight. • Damage Assessment: The aircraft had lost a critical flight control surface, yet still managed a safe touchdown.5. Investigation & Findings • Led by: Transportation Safety Board of Canada (TSB); with multidisciplinary involvement including Airbus, Transport Canada, FAA, BEA (France), NTSB (USA), and others. • Primary Cause: A fatigue (stress) fracture in the composite rudder went undetected through prior inspections. The Airbus inspection program was deemed inadequate for composite materials, particularly for identifying developing defects.