Williams FJ44


The Williams FJ44 is a family of small, two-spool, turbofan engines produced by Williams International for the light business jet market. Until the recent boom in the very light jet market, the FJ44 was one of the smallest turbofans available for civilian applications. Although a Williams design, Rolls-Royce was brought into the project at an early stage to design, develop, and manufacture an air-cooled high-pressure turbine for the engine. The FJ44 first flew on July 12, 1988 on the Scaled Composites/Beechcraft Triumph aircraft.
The Williams FJ33 is a newer, smaller engine based on the basic FJ44 design.

Development

Production started in 1992 with the thrust FJ44-1A. The FJ44-1C is derated to.
The uprated to FJ44-2A was introduced in 1997.
The thrust FJ44-3A was introduced in 2004.
In 2005, a new low end version, the FJ44-1AP, was introduced, with a takeoff thrust.
Released in 2007 was the new thrust FJ44-4. In 2010 this engine was in use on the Cessna CJ4, and since 2018 also on the new Pilatus PC-24.

Design

The FJ44-1A has a single stage blisk fan plus a single intermediate pressure booster stage, both driven by a 2 stage low pressure turbine, and supercharging a single stage centrifugal high pressure compressor, driven by a single stage uncooled high pressure turbine. The combustor is an impingement cooled annular design. Fuel is delivered to the combustor through an unusual rotating fuel nozzle system, rather than the standard fuel-air mixers or vapourisers. The bypass duct runs the full length of the engine.
The FJ44-2A has two additional booster compressor stages.

Variants

;FJ44-1A
;FJ44-1AP
;FJ44-1C
;FJ44-2A
;FJ44-2C
;FJ44-3A
; FJ44-3A-24
;FJ44-3AP
;FJ44-4A
;FJ44-4C
;FJ44-4M
;Williams-Rolls F129

Applications

VariantApplicationTypeDeliveries
FJ44-1Cessna CitationJet CJ1/CJ1+/M2Business jet1993-
FJ44-1SAAB Sk60Jet trainerre-engine
FJ44-2Beechcraft Premier 1ABusiness jet2001-2012
FJ44-2Cessna CitationJet CJ2Business jet2000-2005
FJ44-2Cessna Citation 501SPBusiness jetre-engine
FJ44-2Cessna Citation 550Business jetre-engine
FJ44-2Scaled Composites ProteusExperimental1998
FJ44-2Syberjet SJ30Business jet2007-2009
FJ44-2Learjet 25Business jetre-engine
FJ44-2Virgin Atlantic GlobalFlyerExperimental2005
FJ44-3Cessna CitationJet CJ2+/CJ3+Business jet2004-
FJ44-3Cessna Citation 550Business jetre-engine
FJ44-3Nextant 400XTiBusiness jetre-engine
FJ44-4Cessna CitationJet CJ4Business jet2010-
FJ44-4Hawker 400XPRBusiness jetre-engine
FJ44-4Pilatus PC-24Business jet2018-
FJ44-4MAero L-39 SkyfoxJet trainer
Light attack aircraft		2022-
FJ44-4M-34Alenia Aermacchi M-345Jet trainer2018-
not deliveredCessna 526 CitationJetJet trainer2 prototypes
not deliveredEviation Jets EV-20 Vantage JetBusiness jet1 prototype
not deliveredGrob G180 SPnBusiness jet4 prototypes
not deliveredHawker 200Business jetCancelled
not deliveredLockheed Martin PolecatDroneCrashed
not deliveredLockheed Martin RQ-3 DarkStarDroneCancelled
not deliveredPiper PA-47 PiperJet/AltaireBusiness jet1 prototype
not deliveredScaled Composites TriumphBusiness jet1 prototype

Specifications