TOKYO, Feb. 27_(Kyodo) - Fragments from an aluminum board for repair work on a runway at Narita International Airport caused flat tires on one jumbo jet and damage to tires on three other aircraft when they landed earlier this month, transport ministry officials said Tuesday.
The airport operator is investigating how the fragments were generated, given the danger of a possible crash if such objects are pulled into an engine of a plane taking off from the runway, which logs more than 350 takeoffs and landings per day, the officials said.
The incident occurred on the afternoon of Feb. 1 on Runway A, the longer of the airport's two runways.
The airport authority closed it for a check and found a 4-centimeter thick circular aluminum board, measuring around 40 centimeters in diameter, dislodged from near the median line in the middle of the 4,000-meter runway. They also found several fragments scattered on a nearby taxiway.
The board had been placed to close a hole on the runway following removal of a lamp the night before ahead of pavement work slated for the night of Feb. 1.
The Land, Infrastructure and Transport Ministry said similar aluminum boards are used at domestic airports for runway pavement work and that emergency inspections were conducted right after the Narita incident and no abnormalities were found.
The ministry said since Narita has an exceptionally large number of takeoffs and landings of wide-body aircraft, metal fatigue may have taken place on the board or bolts fixing the board may have been loosened.
