What happened
On November 19, 1998, an Airbus A340-300 was performing its takeoff roll for a flight from Singapore to Frankfurt when the two outermost tires of the right main landing gear burst. Following the tire failure, the quantity indicator for the green hydraulic system dropped to zero, preventing the normal retraction of the landing gear.
The crew decided to abort the takeoff and return to the airport. To ensure a safe landing weight, the necessary amount of fuel was jettisoned before the aircraft returned to the runway. During the subsequent landing roll, a pressure drop was also observed in the blue hydraulic system, which compromised the braking system and nose wheel steering, necessitating the aircraft coming to a halt on the runway.
The investigation
The investigation was conducted by the airline in cooperation with specialized manufacturers, beginning with a comprehensive damage analysis. The investigation focused on the sequence of events that led to the destruction of the tires and the subsequent damage to the aircraft's hydraulic lines.
Findings
The collision of the aircraft with a piece of runway lighting left on the runway was the primary cause of the incident. The impact destroyed the two outer tires of the right main landing gear (tires #4 and #8). Debris from the bursting tires penetrated the landing gear bay covers and damaged the hydraulic lines for the green system located inside the bay. Additionally, hydraulic lines leading to the brakes within the blue system were damaged, which caused the pressure loss noted during the landing roll.
While a tire burst during takeoff is not inherently classified as a severe disturbance, the investigation noted that the resulting damage to the hydraulic lines—despite the protection of the gear bay covers—was significant enough to warrant a review of existing safety concepts.