[3] By 1990, as Boeing was studying the enlarged 767-X, Rolls-Royce was proposing its Trent engine with a larger 110 in (280 cm) fan driven by a new, bigger LP turbine, a modified IP compressor and no exhaust mixer.

[3] The first Boeing 777 with Trent 800 engines flew on 26 May 1995 and ETOPS approval was granted by the FAA on 10 October 1996.

[2] In 1995, the Trent 800 won a large order from Singapore Airlines, a traditional Pratt & Whitney customer.

[14] Japanese KHI and Marubeni Corporation are risk and revenue sharing partners on the Trent 800.

[4] On 17 January 2008, a British Airways Boeing 777-236ER, operating as BA038 from Beijing to London, crash-landed at Heathrow after both Trent 800 engines lost power during the aircraft's final approach.

[15] On 26 November 2008, Delta Air Lines Flight 18 from Shanghai to Atlanta, a Trent 895-powered Boeing 777, experienced an "uncommanded rollback" of one engine while in cruise at 39,000 ft (12,000 m).

The National Transportation Safety Board (NTSB) concluded the cause of both incidents was the same - ice clogging the inlet side of the fuel-oil heat exchanger (FOHE) of the affected engines.

[16] These incidents, along with a similar incident in May 2009 involving an Airbus A330 with Rolls Royce Trent-700 engines, resulted in Airworthiness Directives mandating the replacement of the fuel-oil heat exchangers in similar Rolls Royce Trent series engines.

[17] Rolls-Royce developed a modification to prevent the problem recurring that involved replacing a face plate that had many small protruding tubes with one that is flat.