What happened
On July 13, 2000, an AVRO 146-RJ 100, registration HB-IYX, operated by Crossair, was performing a scheduled flight from Düsseldorf to Zurich. The flight, designated SWR 3513, was being monitored by a training captain seated in the jump seat, with the copilot acting as the flying pilot.
Following an ILS approach to runway 14 at Zurich-Kloten, the aircraft landed successfully. However, immediately after the nosewheel made contact with the runway, the pilot took control of the aircraft, only to find that the plane began to veer sharply to the right. Despite the crew's efforts to maintain directional control, the aircraft exited the runway at approximately 80 knots. The aircraft came to a halt in the grass about 250 meters from the runway, roughly 20 meters to the right of the pavement. The excursion resulted in a burst left main tire and damage to a runway light, but there were no injuries among the 32 passengers or the 3 crew members.
The investigation
The Swiss Transportation Safety Investigation Board (SUST) launched an inquiry in coordination with local authorities. The investigation focused on the mechanical state of the landing gear and the steering system. Investigators examined the nosewheel steering mechanism, the tires, and the brakes. The investigation also considered a broader context of similar incidents involving the BAe 146/RJ aircraft family, noting that a significant number of similar steering-related incidents had occurred globally between 1991 and 2001.
Findings
Technical analysis established that the nosewheel gear was not parallel to the longitudinal axis of the aircraft during the landing roll. This misalignment caused the sudden rightward veer that led to the runway excursion. Notably, neither the aircraft manufacturer, the UK AAIB, nor the Swiss investigators could definitively determine the specific reason why the steering failed to remain centered.
Safety action
Following the incident, the AAIB recommended a modification to the steering valve to expand the neutral band, a measure intended to reduce the probability of future occurrences. Additionally, the manufacturer issued an operational notice instructing crews to check the nose-wheel steering hand-wheel position approximately 500 feet before landing. If the hand-wheel appeared offset, crews were advised to return it to the center position or prepare for potential sudden sideways movement upon touchdown.