MANUFACTURING INNOVATIONS
16 MAY 2017 AIRCRAFT MAINTENANCE TECHNOLOGY
essential elements of a jet engine are materials,
aerodynamics, architecture, and experience.
Dwyer says LEAP represents a step forward in
each of those areas: composite fan blades, com-
posite case, and ceramic matrix composites in the
high-pressure turbine shroud — as well as a high-
pressure hot section compressor that produces an
impressive 22:1 compression ratio (a reduction in
the volume of air 22 times as it passes through the
compressor). This critical ratio is twice that of the
CFM56 family's.
PARING DOWN PARTICULATES
There's a downside to advanced blade aerodynam-
ics. The power-producing airfoils are more suscep-
tible to wear. This susceptibility is felt most keenly
in places such as China, India, and the Middle
East, where Dwyer says, "there's a high concentra-
tion of airborne particulates." CFM's answer to the
problem was to fit LEAP with a debris rejection
The essential elements of a jet engine are
materials, aerodynamics, architecture, and
experience. LEAP represents a step forward
in each area.
By Jerome Greer Chandler
FM's new LEAP powerplant is no mere tweak of
the ubiquitous CFM56. Nor is it a bridge too far. It
is very much an evolutionary engine, but one with
a revolutionary tang to it.
"Basically there are just a few building blocks
of a gas turbine engine," says Bill Dwyer, ser-
vices marketing manager for GE Aviation (CFM
International was formed as a joint company
between GE and Safran Aircraft Engines). The
TAKING THE LEAP:
CFM'S SUCCESSOR
TO THE FABULOUS 56
THE LEAP-1B
powers the
737 MAX.
CFM INTERNATIONAL