A BAe 146-200 was scheduled to operate a scheduled passenger flight from London Gatwick, the United Kingdom to Guernsey Airport, Channel Islands. Onboard 47 passengers, 2 cabin crew and 2 pilots.
The shock damper is shown separated into two parts (source: aaib.gov.uk)
After a normal take-off roll, the aircraft lifted off the runway at Gatwick and once a positive climb was indicated the gear was selected up. The crew could hear the gear travel and shortly afterwards the nose landing was in the up and locked position, the indication for both main landing gear remained red, this indicated that neither gear had locked in the up position. The crew initially continued their flight in accordance with the SID (Standard Instrument Departure) and consulted the emergency checklist for "Gear Selector Up but Gear Does Not Lock Up". When ATC issued an instruction to climb to FL140 the crew requested to maintain FL120 due to a gear issue. The crew actioned the emergency checklist and selected the landing gear down, after which the indication for all three landing gears was green, indicating the gears were down and locked. The secondary gear indication in the cockpit floor, adjacent to the alternate gear handle, also showed green indications for the gears.
BAe 146 Gear Position Indication, either a landing gear lever with a white cover or with I red cover is installed. (Source: aaib.gov.uk)
After using the DODAR decision making principle it was decided to continue the flight to Guernsey with the landing gear down. ATC was informed accordingly and the flight continued to Guernsey. When the crew first contacted Guernsey ATC they informed them about the situation, stating they expected a normal approach and landing. They received radar vectors for an ILS approach to Runway 27. The approach and touchdown were normal however immediately the aircraft started to pull to the left, initially thinking they had blown a tire the aircraft could be kept on the centreline using the rudder. On application of the brakes, no brake action was observed and the co-pilot saw that the Green hydraulic system pressure indication was at 0 psi. He announced "No Brake Pressure Switch To Alternate System" the Captain immediately selected the alternate brakes (using the Yellow hydraulic system) and the aircraft slowed down normally and the runway was vacated.
During the taxi to the parking stand, there was an obvious listing of the aircraft to the left, Once on the parking stand the aircraft was inspected and it was found that;
The #1 (Left-hand outboard) main wheel had burst
The left main landing gear shock absorber had separated into two parts.
The inner cylinder had contacted the quick release coupling of the norma brake (green) hydraulic system, causing it to disconnect.
The inner cylinder had contacted the #1 mainwheel causing it to deflate
the center frame between the main wheel bays was damaged when the gear was initially retracted.
During subsequent runway inspections, several parts of the landing gear of the aircraft were found.
Shock Absorber Cut Away Drawing
(Source: aaib.gov.uk)
The full report from the Air Accident Investigation Branch is available by clicking here
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