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Pratt & Whitney F100

Pratt & Whitney · Aircraft Engine · USA · Cold War (1970–1991)

Pratt & Whitney F100 — Aircraft Engine
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The Pratt & Whitney F100 is an afterburning low-bypass turbofan that powers most of the U.S. Air Force's F-15 Eagle and F-16 Fighting Falcon fleets. Designed in the late 1960s under the USAF "FX" requirement that produced the F-15, it was the first engine to deliver a thrust-to-weight ratio above 8:1 in a production fighter powerplant and replaced the older General Electric J79 turbojet in U.S. front-line service. The F100 entered service in 1972 with the F-15A, and more than 7,300 engines have been delivered since.

The engine uses a 3-stage fan driven by a 2-stage low-pressure turbine, a 10-stage high-pressure compressor driven by a 2-stage high-pressure turbine, an annular combustor, and a fully variable convergent-divergent afterburner nozzle. The original F100-PW-100 produced 23,830 lbf with afterburner and 14,690 lbf dry. Subsequent dash-numbers refined the high-pressure compressor and turbine cooling to extend hot-section life and push thrust to 29,160 lbf in the F100-PW-229 used on later F-15E Strike Eagles and Block 50/52 F-16s. A companion engine, the F401, was developed in parallel for the U.S. Navy's F-14 Tomcat but was cancelled over cost and reliability concerns, leaving the Tomcat with the troubled Pratt & Whitney TF30.

Early F100 service was rocky. The F100-PW-100 suffered stagnation stalls and afterburner blowouts during high-angle-of-attack maneuvering, and turbine hot-section durability fell well short of contract life. By 1984 the Air Force had run out of patience and opened the F-16 to a competing engine, triggering the "Great Engine War" between Pratt & Whitney and General Electric. GE's F110 won a slice of F-16 production starting with the Block 30, and the rivalry forced Pratt & Whitney to deliver the much-improved F100-PW-220 in 1985 with digital electronic engine control (DEEC), a redesigned hot section, and roughly 4,000 hours mean time between removal.

The F100 family now spans three production dash-numbers: the F100-PW-220 (23,770 lbf, the standard F-15C/D and early F-16 Block 25/40 engine), the F100-PW-220E (a -220 retrofit kit applied to older -100 engines), and the F100-PW-229 (29,160 lbf, used on F-15E Strike Eagle, Singapore F-15SG, South Korea F-15K, and F-16 Block 50/52). Foreign operators include Israel, Singapore, South Korea, Japan, Taiwan, Turkey, and most other F-15 and F-16 export customers that did not select the F110.

Production continues in 2026 at the Pratt & Whitney Middletown, Connecticut facility, primarily for F-15EX Eagle II deliveries to the U.S. Air Force and for ongoing F-16 Block 70/72 export orders. The successor-generation Pratt & Whitney F119 powers the F-22 Raptor and shares much of the F100's basic architectural vocabulary, though the F119 adds supercruise and 2D thrust-vectoring.

For Kids — a shorter, friendlier version

The Pratt & Whitney F100 is a jet engine that powers two famous fighter jets. These are the F-15 Eagle and the F-16 Fighting Falcon. Both planes fly for the American Air Force.

This engine was designed in the late 1960s. It first went into service in 1972 on the F-15A. Since then, more than 7,300 of these engines have been built and delivered.

The F100 was a big deal when it came out. It was the first engine ever to push out more than eight times its own weight in thrust. That made it faster than almost any other fighter engine at the time.

Later versions of the engine got even stronger. The most powerful version pushes out about 29,000 pounds of thrust with its afterburner on. The afterburner burns extra fuel to give the plane a huge speed boost. Think of it like a turbo button for a jet!

A similar engine called the F401 was planned for the Navy's F-14 Tomcat. But that project was cancelled because of cost and other problems. The F100 kept going strong and is still one of the most important fighter engines ever made.

Fun Facts

  • The F100 engine first flew in 1972 — that means it has been powering fighter jets for over 50 years!
  • More than 7,300 F100 engines have been built since it entered service.
  • The F100 was the first fighter engine ever to push out more than eight times its own weight in thrust.
  • The strongest version of the F100 produces about 29,000 pounds of force — heavier than a full school bus pushing through the air!
  • The engine powers two famous jets: the F-15 Eagle and the F-16 Fighting Falcon.
  • An afterburner works by spraying extra fuel into hot exhaust gases to create a huge burst of extra speed.
  • A related engine called the F401 was planned for the Navy, but it was cancelled before it ever flew in service.
  • The F100 replaced an older engine called the J79, making American fighter jets much more powerful.

Kids’ Questions

What planes does the F100 engine power?

The F100 engine powers the F-15 Eagle and the F-16 Fighting Falcon. Both of these jets fly for the American Air Force. They are some of the most famous fighter jets in the world.

What does an afterburner do?

An afterburner burns extra fuel to give the engine a big boost of extra thrust. It is like pressing a turbo button to go much faster. Pilots use it when they need a sudden burst of speed.

Why was the F100 engine so special when it was new?

It was the first fighter engine to push out more than eight times its own weight in thrust. No other engine had done that before. That made fighter jets much faster and more powerful than ever.

How many F100 engines have been built?

More than 7,300 F100 engines have been built since 1972. That is a huge number of engines! They have been used in fighter jets all around the world.

Variants

F100-PW-100
Original 1972 production engine for the F-15A/B/C/D Eagle. 23,830 lbf afterburning thrust, 14,690 lbf dry. Suffered stagnation stalls and short hot-section life; most surviving units were rebuilt to -220E standard.
F100-PW-200
F-16A/B variant of the -100 with a back-up control system tuned for single-engine fighter use. Replaced in production by the -220.
F100-PW-220
Major 1985 redesign that ended the early reliability problems. 23,770 lbf afterburning thrust, digital electronic engine control (DEEC), redesigned hot section. Standard engine on F-15C/D and F-16 Block 25/30/40/42.
F100-PW-220E
Retrofit kit that converts surviving -100 and -200 engines to -220 build standard. Lets operators capture the durability gains without buying new engines outright.
F100-PW-229
29,160 lbf afterburning, 17,800 lbf dry. Powers the F-15E Strike Eagle, F-15K Slam Eagle (South Korea), F-15SG (Singapore), F-15EX Eagle II, and F-16 Block 50/52. The dominant in-production dash-number in 2026.
F100-PW-232
Proposed 32,000 lbf upgrade with the same hot section as the F119. Studied for F-16 Block 60 customers but lost to the GE F110-GE-132.

Notable Operators

F-15 Eagle (1972-present)
Primary powerplant for the F-15 air-superiority and Strike Eagle fleets. F-15A/B/C/D fly the F100-PW-100/-220; F-15E/EX/SG/K fly the F100-PW-229. Two engines per airframe. The U.S. Air Force, Israel, Japan, Saudi Arabia, Singapore, and South Korea all operate F100-powered Eagles.
F-16 Fighting Falcon (1979-present)
One engine per airframe. F100-PW-200 powered early F-16A/B; -220 powered F-16C/D Block 25/30/40/42; -229 powers F-16 Block 50/52 and Block 70/72. Roughly half of all F-16s built fly the F100; the other half fly the competing GE F110.

Frequently Asked Questions

What aircraft use the Pratt & Whitney F100?

The F100 powers most of the U.S. Air Force's F-15 Eagle fleet (two engines per aircraft) and roughly half of the worldwide F-16 Fighting Falcon fleet (one engine per aircraft). Foreign F-15 operators including Israel, Japan, Saudi Arabia, Singapore, and South Korea all fly F100-powered Eagles. The remaining F-16s use the competing General Electric F110, chosen by customers including the United Arab Emirates and Egypt.

How much thrust does the F100 produce?

It depends on the dash-number. The original F100-PW-100 produced 23,830 lbf with afterburner; the durability-focused F100-PW-220 produces 23,770 lbf; and the latest F100-PW-229 produces 29,160 lbf with afterburner and 17,800 lbf dry (Pratt & Whitney F100 fact sheet). The -229 is the version on every new F-15EX delivered since 2021.

How does the F100 compare to the GE F110?

They are direct competitors in the same thrust class. The F100-PW-229 produces 29,160 lbf; the F110-GE-129 produces 29,500 lbf. The GE engine is slightly more fuel-efficient in dry thrust; the Pratt engine has a longer service track record. Their competition began with the F-16 "Great Engine War" of 1984-1985, when the U.S. Air Force split F-16 production between the two suppliers to break Pratt's monopoly and force cost discipline. Each engine now powers roughly half of the worldwide F-16 fleet.

Is the F100 still in production?

Yes. Pratt & Whitney still builds the F100-PW-229 at its Middletown, Connecticut plant, primarily for new F-15EX Eagle II airframes being delivered to the U.S. Air Force (USAF F-15EX fact sheet) and for ongoing F-16 Block 70/72 export orders. More than 7,300 F100 engines had been delivered worldwide by 2026.

What's the difference between the F100-PW-220 and F100-PW-229?

Thrust and core design. The -220 is a 23,770 lbf engine introduced in 1985 with digital electronic engine control and a redesigned hot section to fix the -100's durability problems. The -229 is a 1991 upgrade that pushes afterburning thrust to 29,160 lbf via higher turbine inlet temperatures and an improved compressor. The -229 powers later F-15E variants and Block 50/52 F-16s; the -220 remains the F-15C/D and earlier F-16 Block 25-42 engine.

Why was the F401 cancelled?

The F401 was a scaled-up version of the F100 with a larger fan, developed in parallel for the U.S. Navy's F-14 Tomcat. Cost overruns, weight growth, and shared reliability issues with the early F100 led the Navy to cancel the program in 1974. The Tomcat soldiered on with the older, derated TF30 turbofan until the F-14B/D was re-engined with the GE F110 in the late 1980s.

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