Rolls-Royce has delivered the first of its engines designed for Airbus's A380 "super-jumbo", a double-decked aircraft due to enter service in Spring 2006.
The engines have been specially adapted for use on an A340-300 jet in Toulouse in order for them to be flight tested.
The engine will provide 70,000 lbs of thrust at take-off and its makers claim it is the world's cleanest large turbofan engine measured by emissions per pound of thrust.
The manufacturer has also been working to reduce noise emissions from the engine in order to meet regulations for departure at London airports.
The Trent 900 will be used on 48% of Airbus A380s so far ordered. The other planes will use US Pratt & Whitney engines.