What happened
On May 31, 2005, an Air Atlanta Icelandic Boeing 747-400, registration TF-ATJ, was performing a scheduled domestic passenger flight from Madrid to Tenerife Norte Airport. During the final approach to runway 30, the crew encountered significant turbulence and wind shifts. While the approach was initially stable, the aircraft's airspeed fluctuated between 150 and 175 knots during the final 1,000 feet of descent.
As the aircraft reached approximately 10 feet above the runway during the flare, a sudden wind shift occurred. The pilot flying responded with large control inputs to manage the aircraft's attitude. These maneuvers caused the aircraft to exceed its geometric ground contact envelope, resulting in the outboard nacelle of engine number 4 striking the runway surface. The impact caused minor damage to the engine cowling and broke several runway edge lights. The crew and the 403 passengers and 12 crew members on board did not immediately realize the strike had occurred.
The investigation
The CIAIAC investigation focused on the flight dynamics during the flare and the technical state of the aircraft's recording equipment. Investigators analyzed flight data recorder (FDR) parameters, which revealed an unstable approach due to airspeed variations, though the aircraft remained relatively aligned with the centerline.
Crucially, the investigation found that the Cockpit Voice Recorder (CVR) had failed to record the period of the incident. The investigation revealed that the CVR had not been overhauled according to the required maintenance intervals and the tape had become damaged due to an aging capstan drive wheel. This loss of audio prevented investigators from analyzing cockpit callouts and the monitoring performance of the pilot not flying.
Findings
- The primary cause of the incident was the turbulent wind conditions at the airport, which prompted the pilot flying to use large control inputs that exceeded the aircraft's ground clearance limits.
- The aircraft's airspeed was outside of standard operating procedure (SOP) limits during the final stages of the approach, yet the crew did not initiate a go-around.
- The lack of CVR functionality prevented a detailed analysis of crew communication and task sharing during the critical moments of the landing.
- Maintenance oversight regarding the CVR overhaul period and the degradation of the capstan drive wheel contributed to the loss of cockpit audio.