The Rolls-Royce Trent 900 is a high-bypass turbofan developed for the Airbus A380. It belongs to the Trent family of three-shaft engines and was designed around the requirements of a very large, four-engine passenger aircraft. Rolls-Royce identifies it as the fourth member of the Trent family.[1]
Certification and service
The European Aviation Safety Agency awarded the engine its type certificate on 29 October 2004. Certification of the engine was a separate milestone from the later entry of the complete aircraft into passenger service. Rolls-Royce's technical summary gives 2007 as the Trent 900's service-entry year.[2][3]
Its A380 application is central to understanding its size and performance. The engine was developed as one component of a four-engine installation, with each powerplant contributing to the aircraft's take-off and cruise requirements. Engine ratings therefore describe individual powerplants; they should not be confused with the combined thrust available from the aircraft's complete installation.[2]
Mechanical arrangement
The three-shaft arrangement separates the low-, intermediate- and high-pressure rotating systems. Rolls-Royce lists an eight-stage intermediate-pressure compressor and six-stage high-pressure compressor, with separate turbines driving the systems. The low-pressure turbine has five stages, while the intermediate- and high-pressure turbines each have one. This is a different mechanical arrangement from the two-shaft layout used by some competing turbofans.[3]
Fan and core technology
The fan measures 116 inches in diameter and has 24 swept blades. Rolls-Royce explains that the sweep helps manage shock-wave effects near the fast-moving blade tips. The fan containment structure uses titanium, and the high-pressure shaft turns in the opposite direction to the other two shafts. These features address weight, aerodynamic behaviour and efficiency within the large engine.[1]
Performance and evolution
Rolls-Royce's 2016 technical poster lists a 70,000–72,000 lbf thrust range and an overall pressure ratio of 39:1. Such published figures describe the stated product standard and should be read with its date and rating conditions. Later improvement packages incorporated technology from subsequent Trent development, so the name Trent 900 covers engines with successive hardware standards rather than a frozen original configuration.[3][1]