This article discusses ongoing research in the area of turbofans used in jet engines. P&W’s gear facilities in Middletown Connecticut have been developing the fan gearbox over a period of 20 years. The company has a long history of gearbox experience associated with their very popular turboprop gas turbines at Pratt & Whitney Canada. Field tests have shown that the geared turbofan has a much lower level of noise. Currently, some airlines have as much as 35–60% of their operating costs in jet fuel use. If the geared fan engine does indeed significantly reduce fuel use, this improvement in fan performance will be hard for the competition to beat. Another way to improve fan performance is to change the pitch of fan blades, during an aircraft flight cycle. Rotating Composite Technologies, a small firm in Kensington, Conn. has also come up with a unique patented design for the variable pitch fan that promises to overcome the deficiencies of those tested in the 1990s.

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Topics:
Aircraft, Design, Engines, Fans, Flight, Fuels, Gears, Jet engines, Noise (Sound), Thrust, Turbofans, Blades, Composite materials, Cycles, Gas turbines, Jet fuels, Mechanical drives
1.
Mattingly
,
J.D.
,
1996
, Elements of Gas Turbine Propulsion, McGraw-Hill, P.
27
.
2.
Langston
,
L.S.
,
2010
, “Air Race”, Mechanical Engineering Magazine, May, pp.
34
–
38
.
3.
Langston
,
L.S.
,
2009
, “Fitting a Pitch”, Mechanical Engineering Magazine, December, pp.
38
–
42
.
4.
Violette
,
J.A.
 and
Loos
,
E.S.
,
2010
, “Mechanical Design of a Variable Pitch Fan for Turbofan Engines”, Proc. of ASME TURBO EXPO, June 14-18,
2010
, Glasgow, GT2010-22969.
5.
Mazzawy
,
R.S.
,
2010
, “Performance Study for Benefits of Variable Pitch Composite Fan”, Proc. of ASME TURBO EXPO, June 14-18,
2010
, Glasgow, GT2010-22148.
Copyright © 2010 by ASME
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