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CFM LEAP-1B engine begins extensive flight test program

News International-French

18 May 2015

CFM International initiated flight testing of the LEAP-1B engine on April 29 on a modified 747 flying testbed at GE Aviation Flight Test Operations in Victorville, California.

The testing is the next major milestone in a two-year program that will culminate in engine certification in 2016 and delivery of the first Boeing 737 MAX in 2017. The engine behaved well and completed multiple aeromechanical test points at various altitudes during the five-hour, 30-minute first flight.

The LEAP-1B engine is the exclusive powerplant for the Boeing 737 MAX family. The first engine began ground testing on June 13, 2014, three days ahead of the schedule set when the program was launched in 2011.

Over the next several weeks, the flight test program will encompass a comprehensive test schedule that will gauge engine operability, stall margin, performance, emissions, and acoustics. It will also further validate the advanced technologies incorporated in the engine, including the woven carbon fiber composite fan, the twin-annular, pre-mixing swirler (TAPS) combustor, ceramic matrix composite shrouds in the high-pressure turbine and titanium aluminide blades in the low-pressure turbine.

There are currently a total of 26 LEAP engines (all three models) on test, with 10 additional engines in various stages of final assembly.

This LEAP-1B engine is part of the most extensive ground and flight test certification program in CFM's history. The total program, which encompasses all three LEAP engine variants, includes 28 ground and CFM flight test engines, along with a total of 32 flight test engines for the aircraft manufacturers. Over a three-year span, these engines will accumulate approximately 40,000 engine cycles leading up to entry into service. By the time this engine enters service, CFM will have simulated more than 15 years of airline service with 60 different engine builds.

In 2011, Boeing selected the LEAP-1B as the sole powerplant for its new 737 MAX, extending a more than 30-year relationship. CFM has been the only engine provider for the 737 aircraft family since the 737 Classic entered service in 1984.

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