12th of July 2016, Greasing it, Blog #712
- V2Aviation
- Jul 13
- 3 min read
A Beechcraft 1900D operating a flight from Lethbridge Airport (Alberta, Canada) to Calgary International Airport (Alberta, Canada) with 2 crew members and 15 passengers on board. The first officer was the Pilot Flying (PF) with the captain as Pilot Monitoring (PM) for the flight.
After an uneventful take-off at 05:31 lt (local time), the flight climbed to its planned cruise altitude of 11.000 ft ASL. The flight progressed without any issues until on the approach to Calgary International Airport (at ~06.10 lt) when the landing gear was selected down. During the gear-down movement, a grinding, banging noise was heard by the crew. A check of the gear indication showed 1 green down indication for each of the main landing gears, but no green indication light for the nose landing gear. The transit light in the landing gear handle was off. ATC was contacted with a request for radar vectors to perform the appropriate checklist and to cycle the landing gear. This did not resolve the problem; the same indications remained. Approximately 30 minutes after the initial approach, a flyby of the ATC tower was performed. Tower staff reported that the nose landing gear was not in the fully extended position. The nose landing gear was trailing about 20° to 30° below the horizontal retracted position.
After the flyby, the flight entered a holding pattern to further troubleshoot the problem while in contact with the airline's maintenance department. This was unsuccessful. An aircraft from the Calgary Police closed in on the aircraft for a look, confirming the earlier observation and remarking that there were no signs of any fluid (hydraulics) leaking.
With 800 lbs of fuel remaining, the decision was made to land the aircraft with the main landing gear down and the nose landing gear partly extended. At 07:05 LT, an emergency was declared, and vectors were requested for a visual approach to Runway 35R. The passengers received a briefing from the captain on the upcoming emergency landing. At 07.20 lt the aircraft touched down on the main landing gear. At that time, the first officer feathered both propellers,3 placed both engine condition levers in the fuel cut-off position, and pulled both FIRE PULL/T handles. 20 Seconds after the main landing gear touched down, the nose of the aircraft settled on the runway. The aircraft continued on its nose for another 20 seconds, coming to a stop 6950 feet from the runway threshold. Emergency vehicles reached the aircraft in 30 seconds, and all passengers and crew deplaned within 1 minute. There were no injuries; damage to the aircraft was limited to the nose landing gear components, the nose gear door and gear light, as well as 2 propeller tips on each side of the aircraft that contacted the runway. An investigation into the emergency was launched by the TSB (Transportation Safety Board of Canada). It was determined that the failure of the retract-and-extend mechanism of the nose landing gear was initiated by a lubrication problem, causing a pivot/stop bolt to seize. Grease had deteriorated, causing moisture ingress and corrosion. Resulting in a seized component, which led to fatigue cracking and the nose landing gear failing to extend.
The operator examined the condition of nose landing gears in its fleet and found 5 more Beechcraft 1900D aircraft with non-airworthy nose landing gear components.
The TSB concluded that the following findings as to causes and contributing factors played a role in this accident;
The lack of lubrication caused a landing gear component to seize and break, which eventually prevented the nose landing gear from fully extending.
The nose landing gear was not properly lubricated because maintenance personnel were not adequately trained on lubrication and the use of equipment.
The operator's safety management system (SMS) was ineffective at identifying and correcting improper and unsafe maintenance practices relating to nose landing gear lubrication tasks.
The operator's quality control program contributed to ineffective lubrication activities going undetected for an extended period before the occurrence.
Transport Canada’s surveillance of the operator focused primarily on its SMS rather than regulatory compliance. As a result, ineffective lubrication processes went undetected in the process inspection and 2 program validation inspections before the occurrence.
Additional findings as to risk were also mentioned in the final report as issued by the TSB. This report, which served as the source for this blog, can be accessed by clicking on the .pdf file below;
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