Air China has grounded some of its Boeing 787s powered by Rolls-Royce Trent 1000 engines, which had been found to have vulcanization and fatigue cracks in the blades of the engine’s intermediate pressure (IP) compressor.

In April, Rolls-Royce warned airlines that additional checks of its Trent 1000 engine powering the 787 would be needed to better understand the durability of the Package C compressor, featured on nearly 200 787s worldwide.

Air China has replaced the grounded 787s with Airbus A330s and Boeing 777-300s to operate on international routes including Beijing-Los Angeles, Beijing-New York Newark and Beijing-Singapore to avoid flight disruptions as the carrier steps up inspections of Rolls-Royce engines.

Air China is the only Chinese carrier that has equipped its 787 aircraft with Rolls-Royce engines—other domestic airlines including China Southern, Xiamen Airlines and Hainan Airlines all power their 787s with GE engines.

Other affected carriers include Air New Zealand, British Airways, Santiago-based LATAM and UK long-haul carrier Virgin Atlantic.

Beijing-based Air China is the second biggest Boeing 787 operator in China with 14 of the type, following Hainan Airlines, which operates 26 787s.

Air China operates the 787 on domestic routes connecting Beijing with large hubs—such as Shanghai, Chongqing, Chengdu and Shenzhen—as well as long-haul international routes from Beijing.