By IANS,
New York : The propulsion system that will enable the F-35B Lightning II stealth fighter to perform short takeoffs and vertical landings (STOVLs) was successfully operated for the first time during ground testing, Lockheed Martin said Friday.
The F-35B combines the profound advantages of stealth and supersonic speed with the ability to operate from small ships and austere bases near front lines.
At full power, the shaft-driven lift fan propulsion system generates more than 40,000 pounds of lifting force, or about 170 percent more than current-generation STOVL fighters, a company statement said.
Pilot Graham Tomlinson of BAE Systems performed two conversions from conventional to STOVL mode with the aircraft anchored to a specially instrumented hover pit at Lockheed Martin’s STOVL Operations Test Facility at Forth Worth, Texas.
The F-35B is conducting a final series of ground tests before its first flight in early 2009.
“The F-35B’s STOVL propulsion system operated exactly as expected, providing the power output that our models forecast and transitioning very smoothly from conventional to STOVL-mode and back,” said Bobby Williams, Lockheed Martin vice president and F-35 deputy program manager.
“We expect the same kind of seamless transition when the F-35B begins STOVL-mode flights in early 2009,” he added.
The F-35B STOVL propulsion system has logged more than 1,900 hours of operation on test stands.
On July 20, 2001, the X-35B, a proof-of-concept STOVL aircraft using a prototype of the same propulsion system, became the first aircraft in history to perform a short takeoff, accelerate to supersonic speed in level flight and descend for a vertical landing in a single mission.
The STOVL propulsion system comprises a Pratt & Whitney F135 turbofan engine, a drive shaft leading from the engine face to a gear box and clutch connecting to a counter-rotating Rolls-Royce lift fan located directly behind the cockpit.
The F-35B will operate in conventional mode during its initial series of flights to evaluate overall flying qualities and airworthiness.
In early 2009, the F-35B will conduct initial STOVL flight operations before moving to Naval Air Station Patuxent River, Maryland, for further testing.
The F-35 Lightning II is a supersonic, multi-role, 5th generation stealth fighter. The three F-35 variants are derived from a common design and use the same infrastructure worldwide to replace at least 13 types of aircraft for 11 nations, making the Lightning II the most cost-effective fighter programme in history, the company statement said.
Lockheed Martin is developing the F-35 with its principal industrial partners, Northrop Grumman and BAE Systems. Two separate, interchangeable F-35 engines are under development: the Pratt & Whitney F135 and the GE Rolls-Royce Fighter Engine Team F136.
Headquartered in Bethesda, Maryland, Lockheed Martin employs about 140,000 people worldwide and reported $41.9 billion in sales in 2007.