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F103 / CF6-50

In addition to providing topflight power for 12 commercial aircraft, GE's CF6 engines (military designation: F103) earn their military decorations every day. The Electric's CF6-80C2 has been chosen as the C-5's new engineunder the C-5 RERP, based on its ability to provide an affordable, commercially-based solution that enables the venerable Super Galaxy to meet or beat every operational requirement well into the next millennium. A 58% faster time-to-climb capability, 20% increase in cargo loads and 34% improvement in cost per flying hour are just three of the important elements that power the Super Galaxy to unmatched mission superiority.

The General Electric CF6, the Pratt & Whitney JT9D, and the Rolls-Royce RB.211 are three families of modern, large, high-bypass-ratio turbofan engines. Each of these engines is produced in a number of variants with different capabilities. The maximum takeoff thrust of the various versions lies in the range from 45 000 to 55 000 pounds. The bypass ratios of the engines are 5:1 for the Pratt & Whitney JT9D, 5.9:1 and 4.4:1 for the General Electric CF6, and 4.4:1 for the Rolls Royce RB.211. The compressor pressure ratios of the different engines fall in the range from 24:1 to 30:1. The McDonnell Douglas DC-10-30 was powered by three General Electric CF6-50CI engines of 52 500 pounds thrust each but is also available with a version of the Pratt & Whitney JT9D engines.

GE's CF6 engine family has been the most reliable and best-selling commercial engine on wide-body aircraft. The CF6 can trace its beginnings to the early 1960s and the GE TF39 engine. CF6 engines have flown more than 115 million hours by 2006, which is more than any other high-bypass turbofan engine family. The engine powers more than 10 models of wide-body aircraft. The engine family has also played a major role in military aviation, powering transports, tankers and surveillance aircraft.

The F103/CF6 has also powered the KC-10 through two and a half decades of recognized mission accomplishment, fueling it with one of the best dispatch reliability rates and lowest support costs of any major weapon system in the Air Mobility Command. GE's F103 engine, a military version of the very popular CF6 commercial jet engine, helps militaries refuel other aircraft anywhere in the world.

The KC-10A Extender is an advanced aerial tanker and cargo aircraft designed to provide increased global mobility for U.S. armed forces. Although the KC-l0's primary mission is aerial refueling, it can combine the tasks of a tanker and transport aircraft by refueling fighters and simultaneously carrying the fighter support personnel and equipment on overseas deployments. The KC-10's maiden flight took place on 12 July 1980. Ironically, the first aerial refueling occurred during testing in October 1980, with the receiver aircraft being a C-5 Galaxy (also powered by GE engines). The KC-10's three F103 engines produce 52,500 pounds of thrust each enabling the aircraft to transport fuel to the receiving aircraft at a rate of 1,100 gallons (4,180 liters) per minute.

CF6-80C2 engines were also selected to power both the Italian and Japanese B767 Tanker-Transport programs based on their ability to achieve the best possible mission performance capabilities for their respective requirements. CF6 engines also serve as the power of choice for Air Force One, the E-4B, 767 AWACS and Airborne Laser aircraft.

Boeing's YC-14 competed with the McDonnell Douglas YC-15 in the Advanced Medium STOL Transport (AMST) program. Both aircraft were designed to a common cargo specification, and each utilized off-the-shelf engines to achieve a Coanda effect to maximize lifting capability. The Boeing entry used two GE F103/F1A engines mounted forward and above the wing, their exhaust blown across the upper surface of the wing and flap system in order to create powered lift. This location also gave the airplane a quieter noise footprint. Both the YC-14 and the YC-15 satisfied the AMST performance requirements, but the program was canceled before either one of the innovative cargo planes could be chosen for production.

On March 11, 1998 the CF6-80C2 was launched into service on a new military application today with the delivery of two new -80C2-powered Boeing 767 AWACS (Airborne Warning and Control System) aircraft to the Japan Defense Agency (JDA). The JDA launched the 767 AWACS program with an order for four of the advanced aircraft; the two remaining airplanes are scheduled for delivery in 1999.

The new 767 AWACS is the first tactical application for the CF6-80C2, designated the F103-GE-102 for military service. The F103-GE-102 also is the powerplant for Air Force One, a Boeing 747-400 which serves as the private aircraft of the President of the United States. The two aircraft in service have logged more than 20,000 flight hours.

The 767 AWACS fills the need for both airborne surveillance and command and control functions for tactical and air defense forces. The F103-GE-102 supports this mission by providing longer range and time-on-station versus older E-3 AWACS currently in service. In addition, the engine generates ample electrical power for the surveillance and communications equipment necessary to fulfill the AWACS mission, providing countries the state-of-the-art in electronic warfare. The F103-GE-102 has also been selected by the U.S. Air Force to power the new B747-based Airborne Laser aircraft system.

The Federal Aviation Administration (FAA) issued an airworthiness directive (AD) on August 21, 2000 making the time required for previously ordered inspections of General Electric (GE) CF-6 engines more restrictive. The inspections were being done to detect cracking in the high-pressure compressor stage (3-9 spool) that could cause an uncontained engine failure. The compressor in an aircraft engine compresses the incoming air and speeds it up before it enters the combustion chamber to mix with fuel.

The FAA had previously ordered operators of aircraft with CF6 engines to begin inspections effective Jan. 28, 2000. After analyzing an uncontained engine failure experienced by a Varig Brasil Airlines Boeing 767 on June 7, 2000, the agency believed the compliance time before the initial inspection was not restrictive enough. Today's order changes the time before these initial inspections must be done, depending upon the number of start-and-stop cycles the engine has gone through.

Under the August 21, 2000 order, engines with more than 10,499 cycles must be inspected within 500 more cycles, by the next visit to an engine shop or by May 31, 2001, whichever occurs first. Engines that have between 7,000 and 10,499 cycles must be inspected within another 1000 cycles, the next shop visit or by July 29, 2001 which ever occurs first. The engines affected are CF6-45, -50, -80A, -80C2 and -80E1 models. Aircraft with these engines include Boeing 747s, 767s, DC-10s and MD-11s, and Airbus A300s, A310s and A330s. There are about 1,180 such engines in the U. S. fleet, approximately 1400 worldwide.

In 2002 a KC-10 F103-GE-101 incurred a Class A FOD mishap during a local airrefueling mission, when a failure was noted in the number two-engine performance- monitoring coupon. All readings were well off the established baseline. Later during the flight another performance check was made, and hese readings also showed the engine well off the baseline. While accomplishing a go-around, the tower notified the aircrew that sparks were coming out of the number two engine. The aircrew retarded the engine to idle and immediately landed. After taxiing clear of the runway the number two engine was shut down. Initial inspection revealed extensive internal engine damage over $1 million.

The investigation found that an aircraft panel fastener was ingested during flight. It struck a compressor blade, which caused a tear in the blade and led to the blade failing. The failed blade caused extensive compressor and turbine damage. The fastener is common to a number of aircraft in the US Air Force inventory including the mishap aircraft. An inspection of the mishap aircraft revealed no missing fasteners.

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Page last modified: 07-07-2011 02:36:57 ZULU