Cathay Pacific Airways last week grounded four of its Boeing 777-300s, following an incident earlier this month in which part of an engine duct collapsed in flight.

The Oneworld carrier says it checked its entire 777-300 fleet following the 1 December incident and "none of the few suspected 777-300 aircraft will operate until we are entirely sure that it is safe". The other six 777-300s and all five of Cathay's 777-200s continued in service.

On 1 December, the inner surface of the number one engine left-hand D duct collapsed during a 777-300 flight from Bangkok to Mumbai. A metal sleeve around the exhaust sheared off and fell to the ground, hitting a vehicle but not injuring the driver. Cathay says it has concluded that "heat from the engine caused this partial delamination of the duct".

Boeing manufactures the D duct, which houses the thrust reverser and wraps around the engine core. Cathay's 777-300 fleet is powered by Rolls-Royce Trent 884 and Trent 892 engines.

Source: Flight International