What happened
On 24 January 2007, an Air Nostrum Bombardier CL 600-2B19, registration EC-IBM, was performing a scheduled domestic flight from Valladolid to Barcelona. The flight was carrying 40 passengers and a crew of four. During the flight, the crew encountered issues with the aircraft's flaps system, which had experienced intermittent malfunctions on previous legs of the day. During the approach to Barcelona, the flaps failed to extend to the required 8-degree position, triggering a "flap fail" warning on the cockpit's EICAS.
Due to the zero-flaps configuration, the crew had to maintain a higher approach speed of at least 180 kt. During the final approach, the aircraft touched down on runway 2 and 1/2 at an airspeed of 172 kt. Upon contact with the runway, the crew realized that the landing gear had not been deployed. The aircraft performed a long skid on its belly, traveling approximately 1,900 meters before coming to a stop 250 meters from the end of the runway. While no major fire erupted, high temperatures and kerosene leaks were detected, and a fire in the wheel well occurred but remained contained. The aircraft was evacuated, and two passengers sustained slight bruises during the process.
The investigation
The CIAIAC investigation focused on the technical failure of the flaps and the crew's failure to complete the landing checklist. Investigators discovered that water had mixed with the grease in the flap actuation sheaths, causing ice to block the rotation of the flexible shafts during the flight, which had reached temperatures of approximately -40 °C. The investigation also examined the cockpit environment, noting that the crew was overwhelmed by a high density of aural warnings, including EGPWS alerts and the landing gear warning horn. The investigation further analyzed the crew's experience levels and the effectiveness of their communication and checklist usage during the emergency.
Findings
- The primary cause of the accident was the omission to actuate the landing gear extension lever before touchdown.
- A contributing factor was the technical anomaly in the flaps system, which diverted the crew's attention from other critical tasks.
- The landing gear warning horn and EGPWS alerts were not clearly identified or acted upon due to the high volume of simultaneous cockpit warnings.
- The before-landing checklist was not completed by the crew.
- The aircraft's flaps failed to extend because ice had seized the flexible shafts due to moisture contamination in the lubrication system.
- The crew composition lacked sufficient combined experience to effectively manage the complex, multi-layered emergency.