General Electric T700

General Electric T700
Name	General Electric T700
Type	Turboshaft/turboprop
First run	1970s
Manufacturer	General Electric
Status	In service

General Electric T700 The General Electric T700 is a family of turboshaft and turboprop engines developed for rotary-wing and fixed-wing aircraft, used widely on helicopters and transport platforms. It entered service after testing and evaluation programs involving United States Army, Sikorsky Aircraft, Boeing Vertol, and Lockheed, and has been adapted into multiple variants for civil and military customers. The engine underpins programs such as the Sikorsky UH-60 Black Hawk, Boeing CH-47 Chinook derivatives, and international rotorcraft acquisitions.

Development

The T700 program began in response to United States Army requirements for improved performance, reliability, and maintainability over legacy designs like the Turbomeca Artouste and engines used on Bell UH-1 Iroquois platforms. Development involved collaborations among General Electric, contractors including Allison Engine Company engineers, and test centers such as NASA facilities and NAVAIR test sites. Competitive evaluations with powerplants from Rolls-Royce, Pratt & Whitney, and Honeywell Aerospace informed design choices. Certification and military qualification followed trials overseen by Federal Aviation Administration and AMCOM standards, alongside export assessments by Defense Security Cooperation Agency.

Design and Features

The T700 architecture integrates a multi-stage axial compressor, a concentrically designed combustion section, and a two-stage power turbine, reflecting advances similar to turbines developed at General Electric Aircraft Engines and research at Ames Research Center. Its modular construction emphasized field-replaceable modules influenced by maintenance philosophies from U.S. Army Aviation Maintenance doctrine and logistical practices at Wright-Patterson Air Force Base. Features include full-authority control system interfaces compatible with avionics suites by Rockwell Collins, vibration reduction measures informed by testing at Georgia Tech Research Institute, and materials derived from programs at Los Alamos National Laboratory and industrial partners like Carpenter Technology Corporation. The engine’s durability benefited from coatings and cooling methods related to work at Pratt & Whitney Canada research collaborations.

Variants

The T700 family spawned multiple models for diverse missions: military turboshaft variants tailored for platforms procured by United States Marine Corps and Royal Air Force; maritime variants adapted for shipborne operations evaluated by Naval Air Systems Command; and turboprop adaptations explored for fixed-wing transports competing with engines used on De Havilland Canada aircraft. Licensed and joint-production versions involved manufacturers such as IHI Corporation in Japan, Avio Aero in Italy, and Turbomecanica in Romania. Upgraded blocks incorporated improvements similar to those in GE Aviation CF6 and GE90 family developments to meet demands from operators including Republic of Korea Armed Forces and Turkish Armed Forces.

Applications

The T700 powered primary rotorcraft programs including the Sikorsky UH-60 Black Hawk, Sikorsky SH-60 Seahawk, and variants of the Boeing CH-47 Chinook remanufacturing efforts, and has been selected for modernized fleets by nations such as Australia, Japan, United Kingdom, South Korea, Saudi Arabia, and Spain. Civil applications saw use in utility and search-and-rescue rotorcraft similar to platforms operated by Federal Aviation Administration contractors and organizations like Civil Aviation Safety Authority-regulated fleets. The engine also underpinned experimental conversion efforts at institutions such as NASA Glenn Research Center and demonstrations coordinated with European Aviation Safety Agency partner programs.

Operators

Major military operators include the United States Army, United States Navy, United States Marine Corps, Royal Australian Air Force, Royal Air Force, Japan Ground Self-Defense Force, Republic of Korea Air Force, and the armed forces of Saudi Arabia, United Arab Emirates Armed Forces, and Turkish Land Forces. Civil operators encompass helicopter operators certified by Federal Aviation Administration registries, corporate operators in Europe, Canada, and Latin America, and governmental agencies such as coast guards and emergency medical services in Norway and New Zealand.

Performance and Specifications

Typical T700-class specifications vary by submodel but commonly include a power output range comparable to contemporaries from Rolls-Royce and Pratt & Whitney families, with turboshaft ratings in the 1,500–3,000 shaft horsepower range, thermal efficiencies reflecting research from Sandia National Laboratories, and weight and dimensional characteristics aligned with Sikorsky airframe integration schedules. Specific performance metrics such as specific fuel consumption, compressor pressure ratio, and turbine inlet temperature differ across iterations certified under Federal Aviation Administration and military airworthiness standards administered by Department of Defense agencies.

Category:Aircraft engines