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General Electric T700

General Electric Aviation · Aircraft Engine · USA · Cold War (1970–1991)

General Electric T700 — Aircraft Engine
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The General Electric T700 is an American free-turbine turboshaft engine in the 1,500-3,000 shp (1,100-2,200 kW) class, and the workhorse powerplant of every modern U.S. Army and U.S. Navy medium helicopter fleet. Since entering service in 1978 on the UH-60 Black Hawk, more than 20,000 T700 and civil CT7 engines have been built at GE Aviation's Lynn, Massachusetts plant, accumulating well over 100 million flight hours across military and commercial fleets.

GE designed the T700 around a five-stage axial plus one-stage centrifugal compressor, an annular reverse-flow combustor, and a two-stage gas-generator turbine driving the compressor with a separate two-stage free power turbine driving the output shaft. The architecture was chosen for ruggedness and field-maintainability: the engine breaks down into four major modules that can be swapped on the flight line without specialist test equipment, a requirement set by the U.S. Army's 1972 Advanced Attack Helicopter and Utility Tactical Transport Aircraft System programmes. Inlet particle separators integrated into the front frame reject sand and dust so the engine survives desert and brownout operating conditions.

The early T700-GE-700 entered service at 1,536 shp on the UH-60A in 1978. The T700-GE-701 added 174 shp for the AH-64A Apache in 1984, and the T700-GE-701C delivered 1,890 shp for the AH-64D Longbow and UH-60L. Today's T700-GE-701D powers the UH-60M and AH-64E at 2,000 shp continuous, with the higher-output T700-GE-401C at 1,800 shp for the U.S. Navy's MH-60R/S Seahawk, AH-1Z Viper, and other maritime types. A higher-rated CT7-8 derivative at up to 2,520 shp powers the AgustaWestland AW101, AW189, and Sikorsky S-92.

The civil CT7 turboprop variant, with a propeller reduction gearbox replacing the helicopter free-shaft output, powers the Saab 340, CASA CN-235, and earlier Bombardier Dash 8 derivatives. The T406 derivative of the T700 was developed for the V-22 Osprey tiltrotor at 6,150 shp per engine, sharing the core gas generator but with a heavier free turbine and proprotor gearbox interface. GE's Engineered Services group maintains the in-service fleet at Strother, Kansas, and overseas through licensed depots in the United Kingdom, Italy, Japan, and South Korea.

The T700 is in service with more than 50 countries and roughly 130 customers. Production is ongoing — current orders cover U.S. Army UH-60M and AH-64E procurement through 2030, U.S. Navy MH-60R/S buys, and AW101/AW189 deliveries to export customers. The competing engine in this class is the Rolls-Royce / Turbomeca RTM322, fitted to the NH90 and some AW101 variants — but the T700 has the larger installed base and broader airframe coverage. Unit cost runs $700K-1.2M depending on configuration.

The T700 has accumulated combat hours in every major U.S. operation since 1991: Operation Desert Storm (1991), Bosnia and Kosovo (1995-1999), Operation Enduring Freedom in Afghanistan (2001-2021), Operation Iraqi Freedom (2003-2011), Operation Inherent Resolve (2014-present), and a long list of smaller operations. T700-powered helicopters flew the Battle of Mogadishu in 1993 (UH-60 Black Hawks), the assault on Osama bin Laden's Abbottabad compound in 2011 (modified MH-60s), and most U.S. Navy and U.S. Marine Corps casualty-evacuation flights through 30 years of combat operations. Engine survivability under battle damage — single-engine flight after losing the other engine to ground fire, sand-and-dust resistance in Afghanistan, salt-water ingestion tolerance on carrier decks — has been the defining quality the T700 is known for.

For Kids — a shorter, friendlier version

The General Electric T700 is a powerful engine made for helicopters. It was first used in 1978 on the UH-60 Black Hawk helicopter. The American army and navy both use this engine to power their most important helicopters.

The T700 powers some very famous helicopters. These include the AH-64 Apache attack helicopter and the SH-60 Seahawk navy helicopter. Over 20,000 of these engines have been built at a factory in Lynn, Massachusetts.

This engine is built to be tough and easy to fix. It can be taken apart into four big pieces right on the airfield. You do not need special tools or a workshop to swap out the parts. That makes it very useful for soldiers in the field.

The T700 also has a special filter at the front. This filter keeps sand and dust out of the engine. That means the engine keeps working even in hot, dusty deserts. It has flown for over 100 million hours in total — longer than many lifetimes!

Fun Facts

  • The T700 engine has been built more than 20,000 times since 1978.
  • All those T700 engines together have logged over 100 million flight hours.
  • The engine is used in more than 50 countries around the world.
  • Soldiers can swap out engine parts right on the airfield without special tools.
  • A built-in sand filter keeps the engine running in dusty desert conditions.
  • The T700 is smaller than a compact car but powerful enough to lift a helicopter full of soldiers.
  • The engine powers the famous Black Hawk, Apache, and Seahawk helicopters.
  • GE builds both military and civilian versions of this engine at the same factory in Massachusetts.

Kids’ Questions

What helicopters use the T700 engine?

The T700 powers three very famous helicopters. These are the UH-60 Black Hawk, the AH-64 Apache, and the SH-60 Seahawk. The army and navy both use helicopters with this engine.

Why is the T700 good for use in deserts?

The T700 has a special filter built into the front of the engine. This filter stops sand and dust from getting inside and causing damage. That means the engine keeps working even in very dusty places.

How easy is the T700 to fix?

The T700 breaks into four main pieces that are easy to remove. Soldiers can swap these parts right on the airfield. They do not need a special workshop or fancy tools to do the job.

How many T700 engines have been made?

More than 20,000 T700 and related engines have been built so far. They are made at a factory in Lynn, Massachusetts. Together they have flown for over 100 million hours in the air.

Variants

T700-GE-700 (1,536 shp)
Original 1978 production variant for the UH-60A Black Hawk. Set the template for every later T700 with its four-module construction and integrated particle separator.
T700-GE-701/701C (1,690-1,890 shp)
Higher-rated variant for the AH-64A/D Apache (1984) and later UH-60L. The 701C added a redesigned compressor and turbine for the AH-64D Longbow.
T700-GE-701D (2,000 shp)
Current-production variant for the UH-60M Black Hawk and AH-64E Apache Guardian, with FADEC and a 17% power increase over the 701C.
T700-GE-401C (1,800 shp)
Marinised variant for the U.S. Navy SH-60B/F, MH-60R/S Seahawk, and AH-1Z Viper. Salt-water corrosion protection and uprated free turbine.
CT7-8 (2,000-2,520 shp)
Civil and military variant with a redesigned dual-channel FADEC powering the AgustaWestland AW101 Merlin, AW189, and Sikorsky S-92 Helibus.
T406 / Rolls-Royce AE 1107C (6,150 shp)
Tiltrotor derivative for the V-22 Osprey, scaled up to deliver the power needed for vertical lift at twin-engine ratings. Now built by Rolls-Royce as the AE 1107C Liberty.

Notable Operators

Sikorsky UH-60 Black Hawk / SH-60 Seahawk family
Two T700-GE-701D engines on every U.S. Army UH-60M and two T700-GE-401C on every U.S. Navy MH-60R/S. With more than 4,500 H-60s built across all variants, this is the single largest T700 application.
Boeing AH-64 Apache
Two T700-GE-701D engines on every AH-64E Apache Guardian. The Apache's hot-and-high mission profile drove the development of the high-power 701C and 701D variants.
Bell AH-1Z Viper / Bell UH-1Y Venom
Two T700-GE-401C engines on each U.S. Marine Corps H-1 upgrade airframe. Replaced the Lycoming T400 of the earlier AH-1W SuperCobra.
AgustaWestland AW101 / AW189 / Sikorsky S-92
Three CT7-8E engines on the AW101 Merlin, two CT7-2E1 on the AW189, two CT7-8A on the S-92. These civil and military medium-lift helicopters all use the FADEC-equipped CT7-8 family.
V-22 Osprey (T406 derivative)
Two T406 / AE 1107C engines on every MV-22, CV-22, and CMV-22B. The T406 shares the T700 gas-generator core but is roughly three times the rated power.

Frequently Asked Questions

What is the difference between T700 and CT7?

T700 is the U.S. military designation, CT7 is GE's commercial designation. The cores are nearly identical but the CT7 turboshaft variants for civil helicopters carry full FADEC and corrosion protection from the factory, while the CT7 turboprop variants for fixed-wing aircraft (Saab 340, CASA CN-235) add a propeller reduction gearbox. The latest CT7-8 family pushes power to 2,520 shp for the AgustaWestland AW101, S-92, and AW189 — well above any in-production T700 variant.

How does the T700 compare to the Rolls-Royce RTM322?

Both engines occupy the same 1,800-2,300 shp class for medium helicopters and were direct competitors during the 1980s European helicopter programmes. The RTM322 powers the NH90 and some AW101 Merlin variants, while the T700/CT7 family covers everything else. The T700 has a much larger installed base (20,000+ vs around 3,000 RTM322s) and broader airframe coverage, which translates into better global support and lower unit cost.

What power does the T700 produce?

Power ranges from 1,536 shp (early T700-GE-700 on the original UH-60A) up to 2,520 shp on the latest CT7-8E. The U.S. Army's current standard, the T700-GE-701D, is rated at 2,000 shp continuous and 2,675 shp emergency for 30 seconds. The T406 / AE 1107C derivative for the V-22 Osprey is in a different class entirely at 6,150 shp per engine.

How many T700 engines have been built?

More than 20,000 T700 and CT7 engines were delivered between 1978 and 2026, logging well over 100 million flight hours according to GE Aerospace. Production continues at Lynn, Massachusetts, for U.S. Army UH-60M and AH-64E orders running through at least 2030. The T700 family is GE's longest continuously-produced turboshaft.

Why does the T700 use modular construction?

The U.S. Army's 1972 design specification required field-maintainability without depot tooling. GE split the T700 into four modules — cold section, hot section, accessory gearbox, and power turbine — that can be uncoupled and swapped on the flight line by two technicians in under two hours. The integrated inlet particle separator in the front frame also lets the engine run in desert dust without the bolt-on filter that earlier turboshafts needed.

What is the unit cost?

Between $700,000 and $1.2 million per engine depending on variant and quantity, based on recent U.S. Department of Defense contract awards. The T700-GE-701D fitted to U.S. Army UH-60M Black Hawks runs around $1.1M each at the 2024 contract price. Civil CT7-8 engines for AW101 and S-92 cost more because of the FADEC and certification overhead.

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