What happened
On December 24, 1997, a Transavia Boeing 757, registration PH-TKC, was performing a passenger charter flight from Las Palmas to Amsterdam Airport Schiphol. During the approach to runway 19R, the aircraft encountered strong and gusty wind conditions, with winds reported at 240 degrees at 30 knots, gusting up to 43 knots.
As the aircraft descended, the crew transitioned from autopilot to manual flight at approximately 100 feet. During this phase, the aircraft experienced significant turbulence and a sudden yaw. The aircraft touched down heavily on the right main landing gear first. Following a bounce, the pilot applied firm nose-down input, which caused the nose gear to strike the runway while the aircraft was still in a significant crab angle. This impact caused the nose gear doghouse to break and rotate backward, leading to a structural collapse of the nose landing gear.
The aircraft slid approximately 3 km down the runway, veered to the right, and eventually departed the paved surface into the grass. The excursion caused the main gear bogies to sink into soft terrain and strike runway light transformer units. A small fire broke out at the left inner brake unit, which was extinguished by the airport fire brigade. There were four minor injuries among the 205 passengers, while the cockpit and cabin crews were uninjured.
The investigation
The Dutch Transport Safety Board examined the mechanical failure of the nose landing gear, the impact of the wind conditions, and the runway allocation system in place at Schihpol. The investigation included a failure analysis of the nose landing gear wheel well, studies on windshear, and an exploratory study regarding the effects of transitioning from autoflight to manual flight during high crosswind approaches. Investigators also reviewed the cockpit voice recorder and digital flight data recorder to reconstruct the aircraft's pitch and yaw velocity during the touchdown.
Findings
- The primary cause of the gear failure was the hard, crabbing touchdown of the nose gear.
- The crew had misinterpreted the reported wind gusts, believing the maximum gust was 40 knots when the actual reported value was 43 knots.
- The transition from autopilot to manual flight at 100 feet was deemed too low for the prevailing unstable weather conditions.
- The runway allocation system (GPBS) at Schiphol restricted the use of runway 24, which would have provided a much more favorable wind alignment, forcing the aircraft to use runway 19R despite the high crosswind component.
Safety action
Following the accident, several safety recommendations were issued:
- Air Traffic Control should inform pilots of the actual tailwind and crosswind components in addition to general wind information.
- Airlines should include a caution in their manuals regarding the minimum altitude for disconnecting the autopilot during adverse wind conditions.
- The runway allocation system (GPBS) should be reviewed to ensure it aligns with ICAO recommendations and accounts for the unreliability of wind measurements.
- Passenger evacuation procedures should be reviewed, specifically regarding the use of emergency slides in high winds and the impact of communication failures between the cockpit and cabin.