The landing gear collapse on a Raytheon B200 was due to the incorrect installation of a component, according to the ATSB investigation report. On 27 March 2013 a Raytheon B200 aircraft was being operated as an aero-medical flight between Darwin and Port Keats, NT. On board were the pilot and two flight nurses.
While preparing to land at Port Keats, the pilot selected the landing gear down. Only the nose landing gear (green) light illuminated. The unsafe landing gear (red) warning light remained illuminated for the left and right landing gear. The pilot cycled the landing gear and the landing gear circuit breaker tripped. The pilot reset the circuit breaker in accordance with the aircraft’s quick reference handbook, but it tripped again.
The pilot decided to return to Darwin and advised air traffic control (ATC) of the situation. During the flight the pilot completed the unsafe gear checklist including using the emergency gear extension system. While in the circuit area, another company pilot and Darwin ATC reported that the landing gear appeared to be down.
During landing, the right landing gear touched down first, but when the left wheel touched, the aircraft started to sink. The pilot transferred the weight to the right, shut down the left engine and feathered the propeller. He then shut down the right engine and feathered the propeller. The left wing struck the runway and the aircraft skidded to a stop. The pilot and flight nurses exited the aircraft, without injury. The aircraft sustained substantial damage.
During landing, the right landing gear touched down first, but when the left wheel touched, the aircraft started to sink.
The left landing gear had been installed on the aircraft on 22 March 2013 and this was the first flight with the replaced gear. The operator found that a washer had not been installed in the assembly. CASA’s investigation found that there was no conclusive way to determine when the washer installation error had occurred. The manufacturer subsequently commented that the missing washer would not have caused the landing gear to fail to lock down. They believed it was more likely that a drag brace had either, not been installed, or had been rigged incorrectly, or that another landing gear assembly or maintenance error occurred, causing the circuit breaker to trip resulting in the accident.
Following the occurrence, the operator inspected all of its B200 aircraft and issued a safety bulletin to staff. The training and checking department were reviewing its proficiency checking for pilots in relation to this type of landing. The manufacturer is clarifying its maintenance manual.
Read the report: Left main landing gear collapsed involving a Raytheon B200, VH-ZCO, Darwin Airport, Northern Territory, on 27 March 2013