26 September 2014, Blog #549
Updated: Sep 26, 2022
A Beechcraft King Air A100 was flying, its 5th sector of the day, from Moosonee to Timmins Victor M. Power Airport, both in the province of Ontario, Canada. Onboard the aircraft was a crew of two and seven passengers. The previous four flights and this flight had been uneventful when ATC cleared the aircraft to descend to 5000 feet ASL (Above Sea Level).
The aircraft at the position where it came to a stop, just off the runway (© TSB)
When the crew became visual with their destination the IFR (Instrument Flight Rules) flight plan was cancelled by the crew and contacted Timmins Radio, making their intentions clear to land on runway 28.
When 4.5 miles from the runway, at 2000 feet ASL, the flaps were selected to "approach" and the landing gear was selected "down". The crew heard the landing gear motor operate for only 5 seconds, after which it stopped operating. The red (Transit) light in the landing gear handle remained on and non of the green "down and locked" had illuminated, indicating that not a single gear had been extended and locked down. At about the same time both generator off-lights illuminated and the related load meters indicated zero loads. The approach was discontinued, and the crew attempted to use the alternate gear extension system, however, this handle was jammed. While in the traffic circuit the circuit breaker for the landing gear system was reset, but subsequent gear extensions were unsuccessful A fly-by of the airport confirmed that the nose gear was only partially extended and the main gear doors were open.
The aircraft just before touchdown, nose gear partially down, main landing gear doors open and the main landing gears barely visible. (Source; kathrynsreport.com © Unknown)
The crew then briefed the passengers on the upcoming emergency landing. The aircraft was then flown on the approach for runway 28 with the flaps in the "Approach" setting. Over the threshold, the captain set both power levers to idle and the co-pilot then feathered the propellers and placed both condition levers in the cut-off position. The captain meanwhile switched off all electrical power. The aircraft touched down 1530 feet from the threshold and settled on the main landing era doors 1600 feet later, it continued down the runway coming to a stop 40 feet passed the runway end. All occupants exited the aircraft through the main door, there were no injuries, and there was no fire. Damage to the aircraft was extensive, damage was found on the;
Main and nose landing gear doors
Underbelly skin and antennas
The Transportation Safety Board of Canada (TSB) was alerted and an investigation was launched. After completing their investigation the report was released on the 14th of January 2016. In the report the following findings as to causes and contributing factors were presented;
During the extension of the landing gear, a wire bundle became entangled around the landing-gear rotating torque shaft, preventing full extension of the landing gear.
The entanglement by the wire bundle also prevented the alternate landing-gear extension system from working. The crew was required to conduct a landing with only the nose gear partially extended.
The wire bundle consisted of wiring for the generator control circuits, and when damaged, disabled both generators. The battery became the only source of electrical power until the aircraft landed.
The wire bundle wrapped around the torque shaft of the landing gear mechanism. (©TSB)
After the accident, the operators' safety management conducted an investigation, and safety actions were taken. These are presented in the TSB report (also the source for this blog) which is available by clicking on the .pdf file below;