Japan-based All Nippon Airways (ANA) has reportedly said that the 5 grounded 787 jets use a certain type of gear in their Rolls Royce Trent 1000 engines that could lead to a damaged engine gearbox.
‘Damage was discovered in a Rolls-Royce engine gearbox used for endurance testing on the ground. A specific gear showed corrosion due to an issue in the surface treatment at the time of production, which led to damage to the gear box. Certain 787 engines within the ANA fleet have gears produced using the same process, that may possibly lead to corrosion.’
“Working with Boeing, we will replace the part in question and return our fleet to an operating state as quickly as possible,” ANA said.
There is no definitive word on how long the planes will be grounded. The other 6 787s in ANA’s fleet are not affected by the issue and will continue to operate normally.