What happened
On 14 January 2015, a Gulfstream G200, registration EC-KRN, was performing a commercial passenger flight from Dakhla, Morocco, to London Luton Airport. During the landing roll on a wet runway, the aircraft experienced a sudden tyre failure almost immediately after touchdown. Within one second of contact with the runway, a loud bang indicated the burst of the right outboard tyre.
The flight crew noted significant difficulties with directional control and braking effectiveness. Approximately 16 seconds after the initial touchdown, the crew activated the emergency braking system. Following this activation, a series of further loud sounds were recorded, which were identified as the remaining three main tyres bursting. The aircraft eventually came to a halt 3/8 seconds after touchdown, with damage sustained to all four mainwheels and tyres.
The investigation
Because the Digital Flight Data Recorder (DFDR) had failed to record the flight, investigators relied on the Cockpit Voice Recorder (CVR) and the commander's report to reconstruct the sequence of events. The investigation examined the aircraft's braking and anti-skid systems, as well as the physical damage to the landing gear.
Testing of the aircraft's braking, anti-skid, and parking brake systems revealed no mechanical or electrical faults. While the DFDR had not recorded the incident, the cause of this failure could not be determined, though it likely occurred during pre-flight preparations. Examination of the tyres showed that all four had developed flat spots that had worn through the carcass, with the most significant damage found on the right outboard wheel rim.
Findings
- The initial burst of the right outboard tyre likely caused the wheel speed to drop below the threshold for the 'locked wheel' protection, triggering the anti-skid off light.
- This event caused the anti-skid system to remove brake pressure from the adjacent wheel, reducing the total available braking effectiveness by 50%.
- The 16-second delay between the first tyre burst and the selection of the emergency braking system significantly contributed to the extended landing ground roll.
- The subsequent bursting of the remaining three tyres was caused by the loss of anti-skid protection when the emergency brake was applied, allowing the tyres to skid and flat-spot under heavy braking pressure.