Thursday, June 12, 2008

World's Priciest Stealth Plane Takes First Run to Vertical Landing

Needing a boost after a negative report leak, Lockheed Martin tested a prototype of its latest Joint Strike Fighter for the Marines today—a supersonic F-35 that lands like a chopper (with super lift engines) and thinks like a pilot (with a HAL-esque brain).
The Air Force's A-1 model of Lockheed's stealth F-35 fighter jet has been flying for more than a year, but the Marines' next-gen F-35B took off for the first time today. (Photograph Courtesy of F-35 Global Industry Team)

Published on: June 11, 2008

The skies over Fort Worth, Texas, hosted a historic aviation milestone today when the most expensive plane on Earth—a modded version of the F-35 Lightning II that lands vertically like a helicopter—made its first flight. Its pilot certainly had the chops to do the job: He learned to fly short take-off/vertical landing (STOVL) airplanes when Jimmy Carter was president.

Retired Royal Air Force squadron leader Graham Tomlinson, now employed by BAE Flight Systems, flew AV-8 Harriers (the first STOVL warplanes to see action) for 28 years, including time in the late 1980s as a test pilot qualifying the FA-2 Sea Harrier for carrier operations. And today he became the first ever to fly the prototype of the F-35B, a next-gen Lockheed Martin aircraft built for three branches of the U.S military and a host of international partners. The program, at nearly $300 billion, is the most expensive weapons acquisition program in history.

Flight testing has evolved significantly in the years since Tomlinson first flew STOVLs. Computers have so many responsibilities on these planes that they've taken some of the tactile feedback away from pilots. "In the Harrier family, the pilot took care of the aircraft," Tomlinson says. "With the F-35, the airplane takes care of the pilot."

The F-35, known widely as the Joint Strike Fighter, comes in three versions with the same fuselage, identical wing sweeps, and similar tail shapes. The first, a conventional Air Force airplane, A-1, has been flying for more than a year. The STOVL B-model, which will fly for the first time this week, is designed for the U.S. Marine Corps. The last C model will be a larger airplane more suitable for the Navy. (C models will be bulky enough to handle the stresses of the sharp stops associated with hooking cables while landing on aircraft carrier decks.)

Any armed force that operates from ships smaller than aircraft carriers has a soft spot for vertical landers because they can take off from short runways and land on a dime. That's why the U.S. Marines want a stealthy, STOVL airplane that can provide close air support and electronic-jamming missions.

The STOVL F-35 version uses a lift fan engine that can generate 40,000 pounds of lifting force—170 percent more powerful than current-generation STOVL fighters. At the heart of the system is an articulated exhaust outlet that bends to face the ground to support the airplane as it descends. [Check out video of a lift fan engine test from last month here.]

The lift fan that makes it possible for the plane to land vertically is located just 3 ft. behind the pilot's helmet, Tomlinson notes. "When that spins up, you hear this subdued rumble below your head," he says.

The British Harrier was designed in the 1960s, with constant upgrades possibly extending its life to 2020. Pilots who didn't know the airplane's quirks were in real danger, as opposed to the "fly-by-wire" approach of modern aircraft that keeps pilots out of trouble. "There were golden rules for flying Harriers, like ‘You can't let the sideslip or angle of attack build up, or you'll quickly end up killed,' " he says. "You had that drilled into your forehead during training."

In the case of the F-35, the airplane itself is built to react to pilots' commands and follow the golden rules, allowing pilots to concentrate on tactics and mission-related tasks instead of flying. But when a pilot wants this plane to turn a certain direction or pitch, the aircraft itself figures out the best mechanical way to make it happen.

This translates to less pressure for test pilots and far more for flight engineers. The F-35's engineers have filled the airplane's brain with models of flight situations. During the plane's testing phase the engineers need to make sure that those models match reality. It's a long process: F-35B engine and flight tests will stretch until 2009. Today's flight didn't feature an actual STOVL landing, but instead calculated the airplane's handling in conventional flight. Vertical landing test will begin early next year, Lockheed officials estimate.

June has already proven itself as a month of highs and lows for the Joint Strike Fighter program. Several countries, including Israel and Turkey, have deepened their commitments to the program. At the same time, a defense watchdog group released a leaked report from Defense Contract Management Agency that alleged that lead contractor Lockheed Martin lacked control over the project and could not accurately project its costs. Lockheed responds that the complaints are old and have been addressed, but on Capitol Hill, with a new administration on the way into the executive branch, there is blood in the political waters. The fighter program could use some good news this week.

Enter Tomlinson, whose flight will mark a visible milestone in the airplane's development. Flying this plane will be different from flying the F-35A: An F-35B demonstration model is a far heavier plane, but its engine should more than compensate for the girth. "It will still accelerate like a dingbat," says Tomlinson, his pinched English accent somehow making the phrase make sense. "It will still feel sporty in flying, but it will be more stable."

Check back for footage from the flight test later today. In the meantime, this clip below shows Lockeed's 2001 F-35 prototype executing a STOVL landing.

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