The LEAP-1B engine began flight tests on a modified 747-100 flying testbed on 29 April 2015. Click to enlarge.

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 performed 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 and is part of the most extensive ground and flight test certification program in CFM’s history. The first LEAP-1B engine began ground testing on 13 June 2014, three days ahead of the schedule set when the program was launched in 2011.

The 737 MAX is on track to deliver 14 percent more fuel efficiency than today’s most efficient Next-Generation 737s and 20 percent more efficiency than the first Next-Generation 737s to enter service.

—Keith Leverkuhn, vice president and general manager, 737 MAX program, Boeing Commercial Airplanes

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 also will 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.

To date, the 737 MAX has accumulated 2,724 orders from 57 customers worldwide.

LEAP. The LEAP product line, successor to the CFM56 family, incorporates a number of innovative technologies including optimized thermodynamic design, higher bypass and compression ratios, advanced 3-D aerodynamic design and greater use of advanced materials. There are currently three variants in the LEAP engine family, all targeting next-generation single aisle aircraft:

• LEAP-1A: 24,500–32,900 pounds thrust, option on Airbus A320neo
• LEAP-1B: 23,000–28,000 pounds thrust
• LEAP-1C: 27,980 – 30,000 pounds thrust, sole Western powerplant for Comac C919