ACCESS: Secret
5 January 2006
Reaction score
Whilst doing something else I decided to compile a list of General Electric turbine engines with "GExx" designations. GE has obviously used also other designation series, so anyone who wants can add those. Also, as usual, any additions or corrections are welcome.
Note that I'm not certain if the gas turbine GExx designations really belong to the same series.

GE1 J97 first-generation ATEGG turbojet used in AQM-91 and GQM-94
GE2 Gas turbine
GE3 Gas turbine
GE4 Turbojet planned for Boeing 2707 SST
GE5 Gas turbine
GE6 Gas turbine
GE7 Gas turbine (LM2500)
GE8 Turbofan, possible alternative to CFM56
GE9 Turbofan technology demonstrator for AMSA
GE10 Gas turbine/compressor
GE11 ?
GE12 T700 turboshaft used in AH-1W/Z, SH-2G, UH-60, UH-61, AH-63 and AH-64
GE13 Gas generator core used in F101, F108, F110 and CFM56 turbofans
GE14 Second-generation ATEGG turbofan/turboramjet engine
GE15 J101 turbojet used in YF-17
GE16 Advanced turbofan/turboramjet engine
GE17 ?
GE18 ?
GE19 ?
GE20 ?
GE21 Variable cycle turbofan planned for Lockheed AST SST (1979)
GE22 ?
GE23 Third-generation ATEGG variable cycle turbofan based on GE13 (1974)
GE24 ?
GE25 Gas turbine/compressor
GE26 ?
GE27 MTFE turboshaft demonstrator planned for V-22 (1983)
GE28 Turbofan for V/STOL aircraft
GE29 Fourth-generation ATEGG variable cycle turbofan planned for Mach 2 fighters
GE30 ?
GE31 ?
GE32 ?
GE33 ?
GE34 Turboprop planned for C-130WBS (1984)
GE35 ?
GE36 UDF propfan (1983-1986)
GE37 YF120 fifth-generation ATEGG variable cycle turbofan used in YF-22 and YF-23
GE38 T407 turboprop planned for P-7, CH-53K
GE45 Turbofan, scaled-down GE90

Main sources:
Various Flight International issues from the electronic archive http://www.flightglobal.com/pdfarchive/index.html
The Putnam Aeronautical Review vol.2, John Motum, 1990
Fuels and Lubricants Influence on Turbine Engine Design and Performance, Ivan E. Sumey, General Electric Company, 1974 AD/A-004 214
I'm assuming that GE90 is a non-sequential designation with General Electric going for a trendy 1990s tie-in. Likewise, the follow-on GE9X/GEnx designation are just marketing exercises.

Below are some additions/details from an Air Force Magazine article (The Jet Age in Review) and Flight International.

GE1 - Civil/military single-shaft turbofan
- GE1 : Basic core engine, 5,000 lbf
- GE1 : Augmented, 15,000-25,000 lbf
- GE1 : Turboshaft, 10,000 shp
- GE1 : Augmented/vectored, 10,000-20,000 lbf
- GE1 : Augmented turbojet, 75,000 lbf
- GE1 : Cruise fan, 26,000 lbf, MeP.2020
- GE1 : Lift fan, 27,500 lbf
- GE1 : High-bypass turbofan, 20,000 lb
- GE1 : ... 30-odd potential engine designs

GE1/6 - Half-scale technology demonstrator*
- GE1/6: For CX-X program, 15,830 lbf
-- * For full-scale, high-bypass GE TF39

GE1/10 - Lift-Cruise Demonstrator (USAF FX/USN VFX)
- GE1/10 : Augmented, optional vectoring nozzles

GE1/J1A1 - Military single-shaft turbofan
- GE1/J1A1 : 24" diameter, 7,500 lbf reheat

GE2 - aka X370 Lightweight Gas Generator

GE4 Turbojet planned for Boeing 2707 SST
- GE4/J5P : For Boeing 2707-300

GE5 - 6 MW industrial gas turbine, F404 derivative
- GE5/TA : Aerospace Plane
- PGT5 : Industrial turbine with GE10 influence
- NovaLT5-1: Single-shaft industrial electrical generator
- NovaLT5-1: Double-shaft industrial turboshaft engine

GE7 - GE7/DLD Lightweight Turbojet

GE9 Turbofan technology demonstrator for AMSA
-- GE9 intended for General Dynamics FB-111G

GE10 - Industrial HD turbine, derived from PGT10
- GE10-1 : 12 MW electrical power generator
- GE10-2 : Two-shaft, mechanical drive GE10

GE33 - Advanced Turbine Engine Gas Generator
- GE33: Demonstrator ran in the mid-1980s

GE38 - GE27 program replacement
- Turboshaft: GE38-1B (T408)
- Turboprops: T407/GLC38, CPX38*
-- * [Project] 4,000-6,000 shp
- Turbofans : CFE Company CFE738

GE46 - Advanced Turbine Engine Gas Generator

https://www.flightglobal.com/FlightPDFArchive/1967/1967 - 0925.PDF dead link
http://www.airforcemag.com/MagazineArchive/Documents/1997/February 1997/0297engines.pdf
Last edited:
I postulate the GE25 is supposed to be a "half sized F404" ...

According to Leyes and Fleming (The History of North American Small Gas Turbine Aircraft Engines, page 367), the GE25 was an axial compressor research program. Correspondingly, the GE26 was an "axial-centrifugal compressor programs added to centrifugal compressor technology."

All of this seems to have been leading to (or, at least, fed into) the GE27 - General Electric's unsuccessful candidate for the 1967-1983 Modern Technology Demonstrator Engine (MTDE) program (for turboshafts in the 5,000 shp class). GE also studied a turbofan derivative of the GE27. That led, in 1984, to GE and Garrett working together on a joint bizjet turbofan, the 7,000 lbf CFE738, with a GE27-based gas generator. Obviously that CFE738 designation is in the Garrett style but using GE's 38 number.

Another joint designation to throw in here is the GLC38 - the 'General Electric/Lycoming Commercial' derivative of the GE38 (proposed for both the Saab 2000 and DHC-8-400, pp 371-372).
I'm assuming that GE90 is a non-sequential designation with General Electric going for a trendy 1990s tie-in.
It's my understanding that the GE90 was so-called because the fan was 90" in diameter . . .
EDIT: Forget that, the fan was originally 123" in diameter, later versions increased that to128".

Last edited:
More info on the GE1/6 Half-Scale CX-X demonstration? Any photos? The links are no longer available and wayback machine can’t provide

Similar threads

Please donate to support the forum.

Top Bottom