Leap-1C tests commence

CFM International has commenced test flights of the Leap-1C engine, for the Comac C919. The initial test flight lasted 3 hours on a Boeing 747 test aircraft. Pilots say that the engine performed beautifully. Initial testing is to validate aerodynamics and mechanical items. Later testing will validate stall margins, economic performance, and acoustics.

CFM is also developing the -1A and -1B for the A320neo and 737 MAX. Both the -1A and -1C are on track for a 2015 certification.

CFM International has confirmed the maiden test flight of its Leap engine family, beginning with a configuration to be used exclusively by the Leap-1C on the Comac C919.

The test flight, to validate aerodynamics and mechanical items, took place on 6 October using a Boeing 747 testbed at Victorville in California.

CFM says an analysis of the engine’s performance during the flight – which lasted nearly 3h – showed that it “behaved well” and that the test was “very successful”.

www.flightglobal.com...

a reply to: Zaphod58

TBH I'm a little lost.

Do these engines increase fuel economy? do they increase performance? or do they do both? the details from the source are scant.

I have limited knowledge of combustion or turbine engines but all I know is that they evolve slowly over time. Is this leap engine a slight improvement or is it the next big thing?

a reply to: Thecakeisalie

A little of both, but the primary improvement is to efficiency. There's a slight power improvement over the previous engines of similar type, but the fuel burn improvements are the big draw. The Leap-1B, for the 737 MAX, will be 14-20% more efficient that other 737 engines (14% over other 737NGs, and 20% more than the original 737s). The CFM-56 family, which started life on the 737-300 is rated between 18,500, and 27,300 lbs of thrust (static thrust), while the -1B will come in between 23,000 and 28,000 lbs.

The -1A, for the A320neo will see a similar fuel burn improvement (about 15%), while the power rating will be similar. The current A320 has a rating between 25-27,000 lbs, while the Leap-1A will see a rating between 24,500 and 32,000 lbs.

The next big thing is actually the geared turbofan.

a reply to: Thecakeisalie

As near as I can tell,the LEAP program is set to produce higher efficiency engines using the latest materials and technologies.

It has a 'core' jet engine but most of the thrust is generated by a larger turbofan. This generates an air stream that encloses, cools and quiets the jet engine (Fairly standard for turbofan engines).

The fan blades are made of new composite compounds rather than the more traditional fixed pitch Titanium ones, which gives them flexibility and allows them to change their aerodynamic properties according to the speed (centrifugal force) of the engine.

There are also many small incremental improvements of the mechanics of various subsystems.

It is estimated that there will be an approximate 16% improvement in fuel efficiency of the new design and also manufacturing costs wil be very significantly reduced (Titanium is a @#$%^& to work with due to its hardness, thermal resistance and elasticity).

a reply to: chr0naut

The new CMC engine components are going to make a huge difference in engine efficiency.