In May 2006, General Electric finalized the architectural design for the GEnx engine that will power Boeing's recently launched 747-8 Intercontinental and Freighter airplanes. The completion of this milestone begins the detailed design phase for the engine, which is the sole power plant for the 747-8. The front fan for the GEnx engine on the 747-8 will be 105 inches in diameter, compared with 111 inches for the 787. The engine will be rated at 66,500 pounds of thrust for this application. Certification testing will begin in 2006, with flight testing scheduled for late 2008.