See also my own photos of the enormous Airbus A380 Rolls-Royce Trent 900 engine:
The Trent 900 family is designed to power the Airbus A380, for which it is the launch engine. It comes in two thrust ratings, 70,000 and 76,000 lbf (311 and 338 kN) but is capable of achieving 84,000 lbf (374 kN). It features a significant amount of technology inherited from the 8104 demonstrator including its 2.95 m diameter swept-back fan which provides greater thrust for the same engine size, and is also about 15 per cent lighter than previous wide-chord blades. It is also the first member of the Trent family to feature a contra-rotating HP spool and uses the core of the very reliable Trent 500. It is the only A380 engine that can be transported on a Boeing 747 freighter.
In October 2000, the Trent 900 received its first order when Singapore Airlines specified the engine for its order for 10 A380s, quickly followed by Qantas in February 2001. The Trent 900 made its maiden flight on May 17, 2004 on Airbus’ A340-300 testbed, replacing the port inner CFM56-5 engine, and its final certification was achieved on 29 October 2004.
More information about the Trent 900 on Wikipedia: http://en.wikipedia.org/wiki/Rolls-Royce_Trent