Damage has been found in a bolt in the main rotor head of the Ground Self-Defense Force helicopter that crashed in Saga Prefecture in February, government sources said Monday.
The sources think the rotor head of the AH-64D Apache from the GSDF's Metabaru Camp broke apart in mid-air, leading to the fatal accident. Without its rotor, the chopper plummeted onto a house in Kanzaki where an 11-year-old girl was inside.
The two-man crew died while the girl survived.
The government is looking into any link between the damaged bolt and the accident, which it believes was not caused by maintenance crew or pilot error.
The chopper's flight data recorder did not log any abnormalities before the 4:43 p.m. crash on Feb. 5.
The crash killed the 43-year-old pilot and his 26-year-old co-pilot and set the house ablaze. The girl was alone at the time but managed to escape with a knee injury.