What happened
On 24 May 2002, an Airbus A330-243, registration G-EOMA, was performing a scheduled public transport flight from Naples, Italy, to London Gatwick Airport. During the ILS approach to Runway 26L, the aircraft encountered gusty conditions with winds of 17 knots gusting to 30 knots and potential windshear. The approach was flown manually by the first officer with autothrust active.
While the landing was not perceived as unusually firm by the crew or the instructor pilot, air traffic control notified the crew as they vacated the runway that a tyre appeared to have burst. The aircraft stopped on a parallel emergency runway, where the Airport Fire Service confirmed that the No 8 tyre had defered and lost its tread. The crew noted a high brake temperature indication for the No 7 brake on the ECAM, suggesting the system had compensated for the loss of braking on the No 8 wheel.
Subsequent inspections revealed that the thrown tyre tread had caused scuff marks on the right engine nacelle and impact damage to the right inboard flap. The damage exceeded maintenance manual limits. Additionally, the No 4 brake aft wear pin was found to be damaged.
The investigation
The investigation focused on the failure of the No 8 tyre, which had been retreaded twice. Records indicated the tyre had completed 22 landings since being fitted to G-EOMA on 15 May 2002.
Technical analysis by the manufacturer revealed that the tread had completely separated from the casing around the entire circumference and width of the crown. Investigators discovered a 3 mm perforation in the tyre casing at the shoulder. This hole had allowed nitrogen to leak between the tread and the casing during inflation, creating a separation pocket.
Findings
- The primary cause of the incident was a failure to detect a small perforation in the tyre casing during a previous retreading process.
- The leakage of nitrogen through this undetected hole caused the tread to separate from the casing.
- The structural integrity of the tread was compromised, leading to the entire tread peeling off under the stresses of landing loads.
- The loss of the tyre tread resulted in secondary impact damage to the engine nacelle and the aircraft's flaps.