The Lockheed Martin's F-35B Lightning II short takeoff/vertical landing (STOVL) variant has demonstrated during testing that it produces excess vertical thrust - more than required to carry out its missions.

The news was announced by Lockheed Martin's official website.

The tests, conducted on a specially instrumented "hover pit," also validated the performance of aircraft software, controls, thermal management, STOVL-system hardware and other systems.

"The performance level measured was absolutely exceptional," said J.D. McFarlan, Lockheed Martin F-35 Air Vehicle lead.

The Lockheed Martin STOVL customers include the U.S. Marine Corps, the United Kingdom's Royal Navy and Royal Air Force, and the Italian Navy and Air Force.

The F-35B is powered by a single Pratt & Whitney F135 engine driving a Rolls-Royce lift fan. The F135 is the most powerful engine ever flown in a jet fighter.

The testing demonstrated functional operation of all systems required for vertical flight.

"We've demonstrated critical performance such as inlet pressure recovery, pitching moment, rolling and yawing moment, effective vector angles of the exhaust, and control-input response time," said Doug Pearson, vice president of the F-35 Integrated Test Force. "Each of these measurements correlates extremely well with our computer models. The outstanding STOVL performance gives us plenty of confidence to begin in-flight transitions to STOVL-mode flight and ultimately our first vertical landing at the Naval Air Station Patuxent River, Maryland this summer."

The F-35B is the first aircraft to combine stealth with short takeoff/vertical landing (STOVL) capability and supersonic speed. The F-35 is a supersonic, multi-role, 5th generation stealth fighter. Three variants will replace at least 13 types of aircraft for 11 nations initially, making the Lightning II the most cost-effective fighter program in history.

Headquartered in Bethesda, Maryland, Lockheed Martin is a global security company that employs about 146 000 people worldwide and is principally engaged in the research, design, development, manufacture, integration and sustainment of advanced technology systems, products and services.