The CFE738 is a small turbofan engine aimed at the business/commuter jet market manufactured by the CFE Company, and is used on the Dassault Falcon 2000.

The success of the GE27/GLC38 gas generator development of the 1980s led to the formation of the CFE Company by GE and the Garrett Engine Division of Allied Signal (later Honeywell) in 1987.

The CFE738 consists of a single stage fan, driven by a 3-stage low-pressure (LP) turbine, supercharging a 5-stage high-pressure (HP) axial/centrifugal compressor driven by a 2-stage HP turbine. The engine has an overall pressure ratio of 35:1, which is extremely high for an engine with a centrifugal compressor. Other cycle parameters are a bypass ratio 5.3 and airflow of 240 lb/s. The take-off thrust is 5,600 lbf, flat-rated to ISA+15C.

Applications:
Dassault Falcon 2000

Specifications:
Type: Turbofan
Length: 68.3 in
Diameter: 35.50 in (Fan)
Dry weight: 1,214 lb (Basic) Dry Weight: 1,325 lb
Compressor: Fan/Compressor Stages: 1/5+1C
Turbine: High-Pressure Turbine/Low-Pressure Turbine Stages: 2/3
Maximum thrust: Max. Thrust (Sea Level Static): 5,918 lbf, Cruise Net Thrust (Mach 0.8, 40000 ft, ISA): 1310 lbf
Overall pressure ratio: ~30:1, Bypass Ratio: 5.3
Specific fuel consumption: (Sea Level Static): 0.369 lb/hr/lbf, (Mach 0.8, 40000 ft, ISA): 0.645 lb/hr/lbf

General Electric began developing the YF120 for the ATF competition in the early 1980s. Unlike competitor Pratt & Whitney, GE elected against developing a conventional low bypass turbofan and instead chose to design a variable cycle engine. This decision was made as a result of the challenging ATF requirement of supercruise. This meant the engine had to produce a large amount of dry thrust (without afterburner) and therefore have high off-design efficiency (“design” being standard cruise conditions).

The core technology used in the YF120 was developed during two industry-government programs, the Advanced Technology Engine Gas Generator (ATEGG) and Joint Technology Demonstration Engine (JTDE) programs.

The YF120’s variable cycle system worked by varying the bypass ratio of engine for different flight regimes, allowing the engine act like either a low bypass turbofan or nearly a turbojet. As a low bypass turbofan, the engine performed similar to comparable engines. When needed, however, the engine could direct more airflow through the hot core of the engine (like a turbojet), increasing the specific thrust of the engine. This made the engine more efficient at high altitude, high thrust levels than a traditional low bypass turbofan.

An expected disadvantage of this variable cycle system would be increased complexity and weight. GE claims to have combated this by using simple pressure driven valves rather than complex mechanically actuated valves to divert airflow. GE stated that this system resulted in the variable cycle system adding only 10 lb to the engine. Additionally a production F120 engine was expected to have 40% fewer parts than the F110 engine.

The YF120 engine featured a two-dimensional thrust vectoring nozzle. The nozzle allowed for vectoring in the pitch direction. This capability gave the aircraft it was installed in a serious advantage in pitch agility by greatly increasing the amount of nose pitching moment available to the aircraft. The pitching moment is traditionally generated by the horizontal stabilizer (and/or canard, if applicable), but with a thrust vectoring nozzle that moment can be agumented by the thrust of the engine. Furthermore, the pitching moment can be maintained even at low airspeed when the reduced dynamic pressure on the control surfaces makes them relatively ineffective.

GE lost the engine competition for this aircraft to Pratt & Whitney F119. While the YF120 engine never went into production, it was installed in the YF-22 used for the high angle of attack demonstration program as part of the ATF competition. During this demonstration, the YF120 powered aircraft flew, trimmed, at 60 degrees angle of attack at 82 knots. At this attitude the aircraft was able to demonstrate controlibility. Later analysis revealed that the aircraft could have maintained controlled, trimmed flight up to 70 degrees angle of attack.

The YF120 was also proposed as the basis for a more exotic engine, the Turbine-Based Combined Cycle (TBCC) engine that was to be used in demonstrator aircraft like the X-43B and future hypersonic aircraft. Specifically, the YF120 was to be the basis for the Revolutionary Turbine Accelerator (RTA-1). The variable cycle technology used in the YF120 would be extended to not only turn the engine into a turbojet but also into a ramjet. In that mode all airflow would bypass the core and be diverted into the afterburner-like “hyperburner” where it would be combusted like a ramjet. This proposed engine was to accelerate from 0 to Mach 4.1 (at 56,000 ft) in eight minutes.

Applications:
Lockheed YF-22
Northrop YF-23

Specifications:

YF120
Type: Twin-Spool, Augmented Turbofan
Length: 4,242 mm
Diameter: 1,067 mm
Dry weight: 1,860 kg
Compressor: Two stage fan, five stage high pressure compressor (estimated)
Combustors: Annular Combustor
Turbine: Single stage HPT, Counter-Rotating Single Stage LPT
Nozzle: Two Dimensional Vectoring Convergent/Divergent
Fuel type: JP-4 or JP-8
Maximum thrust: 35,000 lbf (160 kN) – class

First run on 20 May 1993, GE evolved the F404 into the F412-GE-400 non-afterburning turbofan for the A-12 Avenger II. After the cancellation of the A-12, the research was directed toward an engine for the F/A-18E/F Super Hornet. GE successfully pitched the F414 as a low-risk derivative of the F404, rather than a riskier new engine. In fact, the F414 engine was originally envisioned as not using any materials or processes not used in the F404, and was designed to fit in the same footprint as the F404.

The F414 uses the core of the F412 and its full-authority digital engine control (FADEC), alongside the low-pressure system from the YF120 engine developed for the Advanced Tactical Fighter competition. One of the major differences between the F404 and the F414 is the fan section. The fan of the F414 is larger than that of the F404, but smaller than the fan for the F412. The larger fan section increases airflow by 16% and is 5 inches (13 cm) longer. To keep the engine in the F404’s footprint, the afterburner section was shortened by 4 in (10 cm) and the combustor shortened by 1 in (2.5 cm). Another change from the F404 is the fact that the first three stages of the high pressure compressor are blisks rather than dovetailed blades, saving 50 pounds (23 kg) in weight. Furthermore, the FADEC guided F414 uses a fuel actuated system to manipulate the afterburner section rather than a separate hydraulic system.

The F414 continued to be improved, both through internal GE efforts and federally funded development programs. By 2006 GE had tested an Enhanced Durability Engine (EDE) with an advanced core. The EDE engine provided a 15% thrust increase or longer life without the thrust increase. It has a six-stage high-pressure compressor (down from 7 stages in the standard F414) and an advanced high-pressure turbine. The new compressor should be about 3% more efficient. The new high pressure turbine uses new materials and a new way of delivering cooling air to the blades. These changes should increase the turbine temperature capability by about 150 °F (66 °C). The EDE is designed to have better foreign object damage resistance, and a reduced fuel burn rate.

The EDE program continued with the testing of an advanced two stage blade-disk (Blisk) fan. The first advanced fan was produced using traditional methods, but future blisk fans would be made using translational friction welding with the goal of reducing manufacturing costs. GE touts that this latest variant yields either a 20% increase in thrust or threefold increase in hot-section durability over the previous F414. This version is called the Enhanced Performance Engine (EPE) and was partially funded through the federal Integrated High Performance Turbine Engine Technology (or IHPTET) program.
As of 2009, the F414-EDE was being developed and tested, under a United States Navy contract for a reduced specific fuel consumption (SFC) demonstrator engine.

Over 1,000 F414 engines had been delivered and the engine family has totaled over 1 million flight hours by 2010.

Variants:

F414-GE-400
This variant flies in the Boeing F/A-18E/F Super Hornet. It was also proposed for the unbuilt naval F-117N variant of the F-117 Nighthawk.

F414-EDE
The “Enhanced Durability Engine” or “EDE” variant, includes an improved high pressure turbine (HPT) and high pressure compressor (HPC). The HPT is redesigned to withstand slightly higher temperatures and includes aerodynamic changes. The HPC has been redesigned to 6 stages, down from 7. These changes were aimed at reducing SFC by 2% and three times greater component durability.

F414-EPE
The “Enhanced Performance Engine” or “EPE” variant, includes a new core and a redesigned fan and compressor. The new engine version offers up to a 20 percent thrust boost, which increases its thrust to 26,400 pounds (120 kN), giving it an almost 11:1 thrust/weight ratio.

F414M
Used by the EADS Mako/HEAT. Derated thrust to 12,500 lbf (55.6 kN) dry and 16,850 lbf (75 kN) wet. This version was proposed for international versions of the Korean T-50 series of trainers and fighter aircraft, but was later superseded by a new offer with a standard F414.

F414G
This variant is produced for the Saab JAS 39 Gripen Demonstrator. It is slightly modified for use in a single engine Gripen contrary to a twin-engine aircraft like the F/A-18. With this engine, the Gripen Demonstrator reached Mach 1.2 in supercruise (without afterburner).

F414BJ
Proposed for Dassault Falcon SSBJ. This variant would produce around 12,000 lbf (53 kN) of thrust without use of afterburner.

F414-GE-INS6
India’s Aeronautical Development Agency selected the F414-GE-INS6 engine to power the Mk II version of the HAL Tejas Light Combat Aircraft (LCA) for the Indian Air Force. 99 engines were ordered in October 2010. The engine was to produce more thrust than previous F414 versions. It features a Full Authority Digital Electronic Control (FADEC) system. The F414-GE-INS6 was to have six stages. The engines were to be delivered by 2013.

F414-GE-39E
Version of F414G for Saab JAS-39E/F Gripen.

Applications:
Boeing F/A-18E/F Super Hornet
EADS Mako/HEAT
Saab Gripen Demo/NG
HAL Tejas Mark II

Specifications:

F414-400
Type: Afterburning turbofan
Length: 154 in (3,912 mm)
Diameter: 35 in (889 mm)
Dry weight: 2,445 lb (1,110 kg) max weight
Compressor: Axial compressor with 3 fan and 7 compressor stages
Combustors: annular
Turbine: 1 low-pressure and 1 high-pressure stage
Maximum thrust: 22,000 lbf (98 kN)
Overall pressure ratio: 30:1
Thrust-to-weight ratio: 9:1