Rolls-Royce T406

The Rolls-Royce T406, company designation AE 1107, is a free-turbine turboshaft engine developed by the Allison Engine Company, now part of Rolls-Royce, to power the Bell Boeing V-22 Osprey tiltrotor. The U.S. Navy selected Allison's engine for full-scale development on 24 December 1985, and it began flight testing on 19 March 1989. It is based on the Allison T56 turboprop combined with the free power turbine of the Allison T701 turboshaft, and it shares a common core with the AE 3007 turbofan and the AE 2100 turboprop. It is rated at 6,000 shp (4,500 kW), and the later Block 3 turbine upgrade raised power by at least 17 percent. Production continued under Rolls-Royce after it acquired Allison in 1995, and a derivative named the AE 1107F was chosen for the Bell MV-75.