- Last April, we dissected the world's most advanced fighter
jet, the F-35B Lightning II, in the pages of our annual "How It Works"
issue. Now military contractor Lockheed Martin is firing up the jet's 40,000-pound-thrust
engine (the most powerful ever built for a fighter jet) in preparation
for flight tests. The jet can soar at supersonic speeds (1,000 mph) and
deflect radar signals, but by the end of the month, pilots are expected
to show off its most highly anticipated feature: the ability to stop mid-flight
and touch down virtually anywhere.
- The F-35B is a "jump jet" variant of the Joint
Strike Fighter (JSF), a futuristic fighter aircraft commissioned by the
U.S. Department of Defense. Its ability to land vertically and make short
takeoffs will allow the Marines to attack targets from much smaller ships
and establish bases without the need for long runways. Barring any disasters
during flight tests, the $300-billion JSF program should put F-35Bs in
service by 2012, when they will begin replacing the Marines' aging fleet
of F/A-18 Hornets and Harrier II fighter jets at bases around the world.
- F-35B - What Makes It Fly
- Lift Fan
- Whereas conventional jet fighters need up to 3,000 feet
of runway to take off, the F-35B pilot simply pushes the throttle forward
and is airborne in less than 500 feet. A computer controls the lift fan,
which pushes cold air down, causing the jet to float up. The air also prevents
hot exhaust from entering the lift fan and stalling the engine. As the
F-35B approaches 288 mph, the wings produce enough lift to let the fan
- Behind the jet's supersonic speed is the Pratt &
Whitney F135 turbofan. During liftoff, the rear exhaust nozzle rotates
to direct the engine's thrust downward, while a drive shaft in front of
the engine turns the lift fan.
- Roll Nozzles
- On the underside of each wing, two computer-controlled
roll nozzles channel a small amount of thrust from the engine to stabilize
the airplane and keep it from rolling out of control.
- A precisely shaped body deflects enemy radar signals
away from the aircraft instead of back toward the source. An internal weapons
bay further minimizes the jet's radar "signature."