The Pratt & Whitney JT12, (US military designation J60) is a small turbojet engine. The J60 conception and project design began in July 1957 at United Aircraft of Canada (later Pratt & Whitney Canada) in Montreal. The project design details were transferred to the main P&W company in East Hartford and in May 1958, the first prototype, with military designation YJ60-P-1 commenced testing.

Flight tests were completed in early 1959; followed by the delivery of the new JT12A-5 engines in July 1959. These were for the two Canadair CL-41 prototype trainers with a rating of 12.9 kN (2,900 lb st).

The modified JT12A-3 turbojets with a basic rating of 14.69 kN (3,300 lb st) were tested in the two Lockheed XV-4A Hummingbird VTOL research aircraft. The next version, JT12A-21, had an afterburner which delivered a maximum thrust of 17.91 kN (4,025 lb st).

A total of 2621 were built.

The Pratt & Whitney T73 (Pratt & Whitney JFTD12) is a related turboshaft engine.

Variants:
YJ60-P-1—prototype

J60-P-3

J60-P-4

J60-P-5

J60-P-6

T73
Military designation of the Pratt & Whitney JFTD12 free power turbine turboshaft version of the J60.

JT12A-3LH

JT12A-5
(J60-P-3/-5/-6) Take-off ratings from 2,900 lbf (12.9 kN) to 3,001 lbf (13.35 kN).

JT12A-6
Essentially similar to the –5

JT12A-7
(J60-P-4) up-rated to 3,300 lbf (15 kN)

JT12A-8

JT12A-21
An after-burning version developing 4,024 lbf (17.9 kN) thrust wet.

FT12
Turboshaft versions for marine use.

JFTD12
Comapny designation of the Pratt & Whitney T73 free power turbine turbo-shaft version of the J60.

Applications:
Civilian (JT12)
Lockheed JetStar
North American Sabreliner

Military (J60)
T-2B Buckeye
T-39 Sabreliner
Sikorsky XH-59/S-69
XV-4 Hummingbird

The Pratt & Whitney J52 (company designation JT8A) is an axial-flow turbojet engine originally designed for the United States Navy, in the 9,000 lbf-class as a scaled-down derivative of the J57/JT3A.

First run in 1955, it was initially intended to power the A4D-3 Skyhawk, an advanced avionics model that was canceled in 1957. After being canceled, the U.S. Air Force selected the J52 to power the AGM-28 Hound Dog cruise missile. The engine was designed with several unique features for this application, including a “conical centerbody mounted in the intake” and a “variable central plug … in the nozzle”.Then, in 1958, the US Navy selected the engine to power what became the A-6 Intruder.

The J52-P-6 model, designed for the YA2F-1 (YA-6A) Intruder, had a unique nozzle that could be angled downward at 23 degrees for STOL takeoffs; this was not used on production A-6s. The J52 was selected to power the A4D-5, another model of the A-4 Skyhawk, remaining in all subsequent new-built models.

The twin-spool J52 employs a split 12-stage axial compressor consisting of a five-stage low pressure unit and a seven-stage high pressure unit. Behind the compressor is a nine-unit can-annular combustion chamber and a two-stage split turbine.

A total of 4,567 were built.

The engine also provided the basis for the Pratt & Whitney JT8D, a civilian low-bypass turbofan engine.

The P&W JT8D was first tested in 1961 resulting in nine basic models.

Variants:
J52-P-3
Flown in: AGM-28 Hound Dog. This variant produced 7,500 lbf (33,000 N) of thrust. The design of the P-3 model included a variable inlet duct to improve engine efficiency at the various altitudes the cruise missile was designed to fly at.

J52-P-6
Flown in: A-6A. This variant produced 8,500 lbf (38,000 N) of thrust and included the 23-degree downward swiveling nozzle.

J52-P6A
Flown in: A-4E, TA-4J, EA-6B (the first few). This variant produced 8,500 lbf (38,000 N) of thrust.

J52-P-8A/B
Flown in: A-4F/G/H/K, TA-4E/F/G/H, A-6E, EA-6B. This variant produced 9,300 lbf (41,000 N) of thrust.

J52-P-408
Flown in: A-4M/N, TA-4KU, EA-6B. This variant included variable inlet guide vanes (VIGV) in the LPC, air-cooled turbine blades, and produced 11,200 lbf (50,000 N) of thrust.

J52-P-409
Also known as PW1212. 12,000 lbf (53 kN) thrust version of the J52-P-408 with an improved low pressure turbine (LPT) and faster acceleration. Designed for the EA-6B and was additionally marketed as an upgrade for the A-4. The J52-P-409 was also proposed as a cost-effective upgrade to the A-6E as an alternative to the A-6F Intruder II, but was not purchased. The P-409 engine was also proposed for use in the EA-6B ADVCAP, but that program was canceled after three prototypes were built and flown. The P-409 would have been available as a new engine or as an upgrade kit for P-408 engines, but was never ordered in significant quantities.

PW1216
An afterburning derivative of the J52-P409 engine proposed for the Grumman Sabre II concept (the project later evolved into the JF-17 Thunder). The afterburner, designed in China, would have increased thrust to 16,000 lbf (71 kN).

JT8A
Company designation for initial versions of the J52

JT8B-1
(J52-P-6)

Applications:
AGM-28 Hound Dog
Dassault Super Mystere
Douglas A-4 Skyhawk
Grumman A-6 Intruder
Lockheed Martin A-4AR Fightinghawk
Northrop Grumman EA-6B Prowler

Gallery

Specifications:

JT8D-1
Thrust: 14,000 lb
Dry weight: 3155 lb

JT8D-209
Thrust: 18,500 lb
Dry weight: 4180 lb

J52-P-408
Type: Turbojet
Length: 118 in (3.0 m)
Diameter: 38 in (0.814 m)
Dry weight: 2,318 lb (1,052 kg)
Compressor: Axial flow, 5-stage LP, 7-stage HP
Turbine: Single stage HP, single stage LP
Fuel type: JP-4
Maximum thrust: 11,200 lbf (50.0kN)
Overall pressure ratio: 14.6 : 1
Specific fuel consumption: 0.89 lb/lbf*hr
Thrust-to-weight ratio: 4.83:1

The J57 was a turbojet development of the XT45 (PT4) turboprop engine intended for the XB-52. As the B-52 power requirements grew, the design evolved into a turbojet, the JT3. The Collier Trophy for 1952 was awarded to Leonard S. Hobbs, Chief Engineer of United Aircraft Corporation, for “designing and producing the P&W J57 turbojet engine”.On May 25, 1953, a J57-powered YF-100A exceeded Mach 1 on its maiden flight. First run in 1952, the engine was produced from 1951 to 1965 with a total of 21,170 built.
One XT57 was installed in the nose of a C-124 (BuNo 52-1069), and tested in 1956.

The Pratt & Whitney J57 (company designation: JT3C). The J57 was the first 10,000 lbf (45 kN) thrust class engine in the United States. The J57/JT3C was developed into the J75/JT4A turbojet, JT3D/TF33 turbofan and the PT5/T57 turboprop.

Variants:
J57-P-1W
11,400 lbf (51 kN) s.t with water injection (B-52B)

J57-P-1WA
As P-1W

J57-P-1WB
As P-1W

J57-P-4A
16,200 lbf (72.06 kN) thrust

J57-P-8A
10,400 lbf (46.26 kN) thrust

J57-P-10
12,400 lbf (55.16 kN) thrust

J57-P-11
9,700 lbf (43.15 kN) thrust, 14,800 lbf (65.83 kN) thrust

J57-P-13
14,880 lbf (66.19 kN) thrust

J57-P-16
16,900 lbf (75.17 kN) thrust

J57-P-20
18,000 lbf (80.07 kN) thrust

J57-P-20A
18,000 lbf (80.07 kN) thrust

J57-P-21
17,000 lbf (75.62 kN) thrust

J57-P-25
15,000 lbf (66.72 kN) thrust

J57-P-31

J57-P-37A

J57-P-43W
13,750 lbf (61.16 kN) thrust

J57-P-43WB
13,750 lbf (61.16 kN) thrust

J57-P-59W
13,750 lbf (61.16 kN) thrust

T57
15,000 hp (11,185.50 kW) turboprop

JT3C-2
Civilian derivative of the J57-P-43WB, 13,750 lbf (61.16 kN) thrust

JT3C-6
13,500 lbf (60.05 kN) thrust

JT3C-7
12,000 lbf (53.38 kN) thrust

JT3C-12
13,000 lbf (57.83 kN) thrust

JT3C-26
Civilian derivative of the J57-P-20, 18,000 lbf (80.07 kN) thrust

JT3D/TF33
A turbo-fan derivative of the J57.

PT5
Company designation for the T57.

Applications:
J57 (Military)
Boeing B-52 Stratofortress (dash 1W, 1WA, 1WB)
Boeing C-135 Stratolifter and KC-135 Stratotanker
Convair F-102 Delta Dagger (dash 25)
Convair YB-60 (dash 3)
Douglas A3D Skywarrior (dash 10)
Douglas F4D Skyray (dash 8, 8A, 8B)
Douglas F5D Skylancer
Lockheed U-2
Martin B-57 Canberra
McDonnell F-101 Voodoo (dash 55)
North American F-100 Super Sabre (dash 21 and 21A)
Northrop SM-62 Snark
Vought F-8 Crusader (dash 8)

JT3C (Civilian)
Boeing 707
Boeing 720
Douglas DC-8

T57 turboprop
Douglas C-124 Globemaster II testbed
Douglas C-132 (not built)

Specifications:
JT3C-7
Type: civil turbojet
Length: 136.77in (3474mm)
Diameter: 38.8in (985.5mm) LP compressor inlet
Dry weight: 3495lb (1585kg) dry
Compressor: all-axial, 9-stage LP compressor, 7-stage HP compressor
Combustors: cannular, 8 flame tubes
Turbine: all-axial,single stage HP turbine, 2-stage LP turbine
Maximum thrust: 12030 lbf (53.5 kN) @ Take-off, SLS, ISA
Overall pressure ratio: 12.5:1
Specific fuel consumption: 0.785 lb/hr/lbf (22.24g/s/KN) @ Take-off, SLS, ISA and 0.909 lb/hr/lbf (25.75g/s/KN) @Max Cruise 3550lbf M0.85,35000ft,ISA
Thrust-to-weight ratio: 3.44

J57-P-23
Type: Afterburning turbojet
Length: 244 in (6,200 mm)
Diameter: 39 in (1,000 mm)
Dry weight: 5,175 lb (2,347 kg)
Compressor: Two-spool 16-stage axial compressor
Maximum thrust: 11,700 lbf (52.0 kN) dry, 17,200 lbf (76.5 kN) with afterburner
Overall pressure ratio: 11.5:1
Turbine inlet temperature: 1,600 °F (870 °C)
Specific fuel consumption: 2.10 lb/(h·lbf) (214.2 kg/(h·kN)) with afterburner
Thrust-to-weight ratio: 3.32:1 (32.6 N/kg)

In 1967, the United States Navy and United States Air Force issued a joint engine Request for Proposals (RFP) for the F-14 Tomcat and F-15 Eagle fighters. The combined program was called Advanced Turbine Engine Gas Generator (ATEGG) with goals to improve thrust and reduce weight to achieve a thrust-to-weight ratio of 9. The program requested proposals and would award Pratt & Whitney a contract in 1970 to produce F100-PW-100 (USAF) and F401-PW-400 (USN) afterburning turbofan engines (company designation JTF22). The Navy would cut back and later cancel its order, choosing to continue to use the Pratt & Whitney TF30 engine from the F-111 in its F-14.

Pratt & Whitney F100 / JTF22 / F401 Article

Variants:
F100-PW-100
The F100-100 first flew in an F-15 Eagle in 1972 with a thrust of 106.4 kN (23,930 lbf). Due to the advanced nature of engine and aircraft, numerous problems were encountered in its early days of service including high wear, stalling and “hard” afterburner starts. These “hard” starts could be caused by failure of the afterburner to start or by extinguishing after start, in either case the large jets of jet fuel were lit by the engine exhaust resulting in high pressure waves causing the engine to stall. Early problems were solved.

F100-PW-200
The F-16 Fighting Falcon entered service with the F100-200, with only slight differences from the -100. Seeking a way to drive unit costs down, the USAF implemented the Alternative Fighter Engine (AFE) program in 1984, under which the engine contract would be awarded through competition. The F-16C/D Block 30/32s were the first to be built with the common engine bay, able to accept the existing engine or the General Electric F110.

F100-PW-220/220E
The F100-PW-220 incorporated the most advanced technology available, including the precision control and advanced maintenance features of digital electronic controls and the extended durability and reliability of metallurgical and heat-transfer advances. The F100-220 was introduced in 1986 and could be installed on either an F-15 or F-16. A non-afterburning variant, the F100-PW-220U powers the Northrop Grumman X-47B UCAV. The “E” abbreviation from 220E is for equivalent. The abbreviation is given to engines which have been upgraded from series 200 to 220, thus becoming equivalent to 220 specifications.

F100-PW-229
Using technology developed from the F119 and F135 engine programs for the F-22 Raptor and F-35 Lightning II, the production F100-PW-229 incorporates modern turbine materials, cooling management techniques, compressor aerodynamics, and electronic controls. The first -229 was flown in 1989 and has a thrust of 79 kN (17,800 lbf) (dry thrust) and 129.7 kN (29,160 lbf) with afterburner. It powers late model F-16s and the F-15E Strike Eagle.

Applications:
F100
McDonnell Douglas F-15 Eagle
McDonnell Douglas F-15E Strike Eagle
General Dynamics F-16 Fighting Falcon
Northrop Grumman X-47B

F401
Grumman F-14B Tomcat (planned; test aircraft only)
Rockwell XFV-12
Vought Model 1600 (proposed)

Specifications:
F100-PW-229
Type: Afterburning turbofan
Length: 4,900 millimetres (191 in)
Diameter: 880 millimetres (34.8 in) inlet, 1,180 millimetres (46.5 in) maximum external
Dry weight: 1,700 kilograms (3,740 lb)
Compressor: Dual Spool Axial compressor with 3 fan and 10 compressor stages
Bypass ratio: 0.36:1
Combustors: annular
Turbine: 2 low-pressure and 2 high-pressure stages
Maximum thrust: 79 kilonewtons (17,800 lbf) military thrust, 129.7 kilonewtons (29,160 lbf) with afterburner
Overall pressure ratio: 32:1
Turbine inlet temperature: 1,350 °C (2,460 °F)
Specific fuel consumption: Military thrust: 77.5 kg/(kN·h) (0.76 lb/(lbf·h)) Full afterburner: 197.8 kg/(kN·h) (1.94 lb/(lbf·h))
Thrust-to-weight ratio: 7.8:1

Aware of the competition from the Rolls-Royce Conway turbofan, Pratt&Whitney decided to develop the JT3D turbofan from the JT3C turbojet for later deliveries of the Boeing 707 and the Douglas DC-8, then nearing entry into service. A 2-stage fan, based on work done on the J91 nuclear turbojet, replaced the first 3 stages of the 8-stage JT3C LP compressor. On the LP turbine, the second stage was enlarged and a third stage added. On the Boeing 707 the fan nacelle was relatively short, whereas the Douglas DC-8 installation had a full length fan cowl. First run in 1958 and flown in 1959 (under a B-45 Tornado test aircraft), Pratt & Whitney provided a kit whereby JT3C’s could be converted to the JT3D standard in an overhaul shop.

In 1959, important orders for the engine were the Boeing 707-120B and Boeing 720B when American Airlines ordered one 707 powered by JT3D turbofans and KLM ordered a JT3D powered Douglas DC-8. The earlier 707s had been powered by the turbojet JT3C and the improved efficiency of the turbofan soon attracted the airlines. A JT3D powered 707-123B and 720-023B (the suffix B was to indicate a turbofan powered aircraft) entered service with American Airlines on the same day, March 12, 1961.

The Boeing KC-135 Stratotankers were all originally powered by turbojet engines. With the demise of many airline 707s the United States Air Force took the opportunity to buy the surplus airframes and use the engines to re-engine the KC-135As used by the Air National Guard and reserve squadrons with the civilian JT3D (designated TF33-PW-102). Over 150 aircraft were modified and the former KC-135A were re-designated the KC-135E.

135 KC-135s use the JT3D while 354 were fitted with CFM International CFM56 engines which provide greater thrust and increased operational flexibility due to their lower noise footprint. The noise of the JT3D is one of the reasons NATO has debated re-engining their E-3 Sentry AWACS fleet, with the aircraft subject to restrictions that modern-engined aircraft are not. Operational flexibility would be further increased due to the ability of higher power engines to increase the ceiling of the aircraft, extending the horizon for radar surveillance; for instance, RAF, French and Saudi E-3s routinely fly higher than NATO/USAF counterparts.

the Boeing B-52H Stratofortress is fitted with the JT3D (in TF33 form). The ‘H’ model of the B-52 was the only production variant of the bomber to be fitted with turbofan engines.

About 8,600 JT3Ds were produced between 1959 and 1985.

Variants:

JT3D-1
17,000 lbf (75.62 kN) thrust civil version, (Water injection optional)

JT3D-2
(TF33-P-3) 17,000 lbf (75.62 kN)

JT3D-3
18,000 lbf (80.07 kN), (Water injection optional)

JT3D-3A
(TF33-P-5) 18,000 lbf (80.07 kN)

JT3D-3B
18,000 lbf (80.07 kN) thrust civil version

JT3D-5A
(TF33-P-7) 18,000 lbf (80.07 kN), (Water injection optional)

JT3D-8A
(TF33-P-7) 18,000 lbf (80.07 kN), (Water injection optional)

JT3D-7
19,000 lbf (84.52 kN) thrust civil version

JT3D-15
22,500 lbf (100.08 kN) thrust civil version for the unbuilt 707-820

TF33-P-3
17,000 lbf (75.62 kN) thrust for the Boeing B-52H Stratofortress

TF33-P-5
18,000 lbf (80.07 kN) thrust for the Boeing KC-135 Stratotanker

TF33-P-7
21,000 lbf (93.41 kN) thrust for the Lockheed C-141 Starlifter

TF33-P-11
16,000 lbf (71.17 kN) thrust for the Martin B-57 Canberra

Aircraft applications:

Civilian (JT3D)
Boeing 707
Douglas DC-8
Shanghai Y-10

Military (TF33)
B-52 Stratofortress
Boeing C-18
C-135B Stratolifter
E-3 Sentry
E-8 Joint STARS
KC-135E Stratotanker (JT3Ds from surplus civil 707 airliners)
VC-137B/C Stratoliner
C-141 Starlifter
Martin RB-57F

Specifications:
JT3D-1
Type: Turbofan
Length: ~138in (3505mm) flange-to-flange
Diameter: ~51.57in (1310mm) fan tip
Dry weight: ~4360lb (1978Kg) bare engine
Compressor: Axial flow, 2-stage fan, 6-stage IP compressor and 7-stage HP compressor
Combustors: cannular, 8 flame tubes
Turbine: Axial flow,single stage HP turbine and 3-stage LP turbine
Maximum thrust: 17,000 lbf (75.6 KN)Take-off (flat-rated to ISA); partial thrust restoration with water injection
Overall pressure ratio: ~12.5:1; bypass ratio 1.42:1
Turbine inlet temperature: ~1150K @Take-off,SLS,ISA
Specific fuel consumption: ~0.78lb/hr/lbf (22.09g/s/KN) @ 4000lbf thrust M 0.82,35000ft,ISA
Thrust-to-weight ratio: 3.9 bare engine

TF33-PW-7
Type: Turbofan
Length: 6200 mm
Diameter: 1000 mm
Compressor: Axial flow, 7-stage LP
Maximum thrust: 21,000 lbf

The Pratt & Whitney T73 (company designation JFTD12) is a turboshaft engine developed from the Pratt & Whitney JT12. Based on the JT12A, the T73 powered the CH-54 Tarhe/Sikorsky S-64 flying crane heavy-lift helicopter. Turboshaft versions for naval use are known as the FT12.
352 were built.

Applications:
Sikorsky CH-54 Tarhe (T73)
Sikorsky S-64 Skycrane (JTFD12)