What happened
On 25 September 2003, a Beechcraft 58 Baron, registration N23659, was conducting a training flight at Alderney, Channel Islands. The purpose of the flight was to re-validate the commander's multi-engine rating and renew his instrument rating. The flight involved various maneuvers, including stalls, go-arounds, and general handling exercises. During the final approach, the pilot planned to use asymmetric power and had notified Air Traffic Control that the landing gear would be extended late in the approach.
At approximately 450 feet above ground level, after the gear selector was moved to the down position, the examiner noted that the three green 'down and locked' indicator lights were not visible. The commander, who had previously set the indicator lights to the DIM setting, switched them to BRIGHT. Upon doing so, both crew members observed the three green lights. However, upon touchdown, it became evident that the landing gear had not actually deployed. The aircraft slid on the underside of its fuselage and came to a stop on the grass adjacent to Runway 08. There were no injuries to the two crew members on board.
The investigation
Investigators examined the aircraft and the landing gear system following the accident. Airfield Fire Service personnel noted that the landing gear selector was found in the DOWN position. During the recovery process, the gear was successfully lowered manually. A maintenance engineer conducted extensive testing on the aircraft and determined that the landing gear and the associated warning horn were fully functional and operated normally.
On this specific aircraft model, the landing gear indicator lights are triggered by the output mechanism of the electric motor rather than microswitches on the gear itself. The light switch features three settings: DIM, BRIGHT, and TEST. The TEST setting briefly illuminates a red 'unsafe' light followed by the three green 'down and locked' lights.
Findings
- The investigation established that the landing gear remained retracted during the final approach despite the crew's belief that it had been deployed.
- It was determined that while switching the indicator lights from DIM to BRIGHT, the pilot may have inadvertently moved the switch to the TEST position, which briefly displayed the green lights and created a false sense of security.
- Neither the pilot nor the examiner reported hearing the landing gear warning horn during the flight or the final approach.