Released: 12 Jan 2000
This first fit check of the F-22 Raptor's 20mm gun system, called the Linear Linkless Ammunition Handling System, was deemed a complete success.
"We took the qualification gun system and perfectly fit it into the midsection of 4008 without one single envelope violation," said Senior Master Sgt. Rod McDowell, a representative of the Armament Integrated Product Team for the F-22 System Program Office.
"The fit check was an unqualified success since all clearance and maintenance goals were met," said Alan Fritsche, the Integrated Product Team leader for the F-22 gun system at Lockheed Martin TAS. "The demonstration once again proves the ability of computer solid modeling to accurately represent the most intricate design details."
In addition to the installation and removal of the 20mm gun and ammunition container, many other gun system components were connected and demonstrated, including the adjustment and actuation of the gun safing mechanism, the compatibility and accessibility of the gun loader system interface and access to all gun-related maintenance items.
The F-22 gun system incorporates many design improvements over previous systems. The system has met extremely challenging weight goals while providing many innovative maintainability features. Several major system components have been integrated or eliminated to simplify gun system installation and removal. The system, which contains 480 rounds of 20mm ammunition, is capable of feeding it to the gun at a rate of 100 rounds per second. To maintain aircraft stealth, the system includes integral hydraulic features that operate fast-acting port and purge system doors.
The ammunition handling system is manufactured by General Dynamics Armament Systems in Burlington, Vt. Qualification testing of the system, including extensive live-fire testing, has been completed. The qualification system used in the fit checks had previously fired more than 80,000 rounds of 20mm ammunition successfully in separate tests (one aircraft lifetime is represented by 52,000 rounds).
Airborne gun fire testing is anticipated to begin on the third flying F-22 in mid-2002, though flight test scheduling opportunities may permit firing before that date.
Tactical Aircraft Systems is a major participant in the F-22 program, led by Aeronautical Systems in Marietta, Ga. Tactical Aircraft Systems is responsible for the mid-fuselage section; electrical, hydraulic, fuel and armament subsystems; flight control system; electronic combat; communication, navigation and identification systems; and the stores management avionics. Program management and final assembly are based in Georgia.
Laboratory facilities supporting the F-22 in Fort Worth include a handling qualities simulator, vehicle system simulator, fuel system simulator and several integration labs associated with flight controls, hydraulic systems, communication/navigation/identification systems, stores management system and integrated maintenance information systems.
Lockheed Martin TAS is a leader in the design, development, systems integration and support of fighter aircraft. Its customers include the military services of the United States and allied countries throughout the world and employs approximately 11,000 people at facilities in Fort Worth, Texas, and is a unit of Lockheed Martin Corp. Lockheed Martin is headquartered in Bethesda, Md., and is a global enterprise principally engaged in the research, design, development, manufacture and integration of advanced-technology systems, products and services. The corporation's core businesses are systems integration, space, aeronautics and technology services. (Courtesy of ACC News Service)
* F-22 Raptor Watch
* Air Combat Command