Created Tuesday, Aug 13th 2024 21:39Z, last updated Monday, Aug 4th 2025 14:22Z
An Atlas Air Boeing 747-400 freighter, registration N404KZ performing flight
5Y-7106 from Tokyo Narita (Japan) to Los Angeles,CA (USA), was climbing through FL140 out of Tokyo's runway 16R when the crew stopped the climb and descended back to FL100 reporting a hydraulic failure. The aircraft entered holds and landed back on Narita's runway 16R about 3.5 hours after departure. Two aft left body gear tyres as well as those wheels were found damaged disabling the aircraft on the runway.
The runway was closed for about 7 hours until the aircraft was moved to the apron.
The aircraft is still on the ground in Tokyo 10 days after landing.
Japan's TSB reported: "The aircraft took off from Narita International Airport at 21:39 on August 12, but immediately afterwards, the aircraft's hydraulic system malfunctioned and the cabin pressure dropped below normal during the flight, leading to the declaration of an emergency and the return flight. The aircraft landed on runway A at the airport at 1:12 on August 13 and stopped on the runway. The runway was closed until the aircraft was moved by a tow truck (until 8:09). An inspection after arrival confirmed that a left main landing gear tire had burst and the aircraft had been damaged." The TSB is investigating the occurrence rated an accident.
On Aug 4th 2025 the JTSB released their final report in Japanese (an English version is to be expected in due time) concluding the probable causes of the accident were:
It is highly probable that this accident occurred when the #7 and #8 tyres were damaged during the aircraft's taxi run. The crew continued takeoff with the main wheels exposed causing fragments of the broken wheels to impact and damage the ceiling pressure bulkhead of the landing gear well.
It is possible that decreasing pressure in the #7 tyre causing an increase in load on the #8 tyre or fragments of the #7 tyre or wheel debris damaged the #8 tyre.
It is possible that #7 tyre lost pressure, however, the cause of that loss of pressure could not be identified.
The JTSB analysed in part that video footage showed the #7 tyre in sync with the #7 wheel along with sounds that appeared to be impacts and pops while taxiing along taxiway A between taxiways W5 and W6, the detached tread also causing damage to the #1 and #4 brake hydraulic systems. During the takeoff run spray like white smoke appeared, it is assumed that the hydraulic system pipes were damaged leading to the subsequent hydraulic malfunction. After the gear was retracted it is presumed that fragments separated and impacted the pressure bulkhead of the main landing gear well.
Related Flight:
5Y7106,
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