The Buzz

America's First Stealth Fighter: The Legend of the F-117 Nighthawk

The F-117 Nighthawk, America’s original stealth plane with a deeply sinister appearance, is an example of a weapon system designed around the limitations imposed by a promising new technology. The Nighthawk was revolutionary when it entered service in 1983—not that many could appreciate that, as the plane was kept secret from the public for five years.

Ironically, the Pentagon had a Russian researcher named Pyotr Ufimtsev to thank for first elaborating in a 1964 paper the concept that visibility on radar was not based purely on the size of an object, but also the angle at which radar waves reflected off its edges. Ufimtsev devised a method for calculating the Radar-Cross Section of objects, determining how visible they are on radar.

Ufimtsev’s research attracted attention in the United States rather than Russia, and in the late 1970s Lockheed Martin began working on the Have Blue project to design a plane with the smallest radar cross section possible. The key was to employ flat surfaces that reflected radar waves away from the transmitter.

When Lockheed rolled out the first two prototypes in 1977, the angular aircraft looked like nothing that had been seen before—or since. Later stealth designs such as the B-2 Spirit and the F-35 feature curved surfaces. However, the F-117 was designed before there were advanced computers with the calculating power to produce such curved surfaces. Thus, the F-117 alone among stealth aircraft is distinguished by its faceted 2-dimensional design.

The constraints this imposed meant the design was aerodynamically unstable, and required sophisticated fight computers combined with quadruple-redundant fly-by-wire controls to compensate and keep the aircraft in a flyable state. The Have Blue prototypes earned the nickname “Wobbly Goblins,” and both crashed during the testing process.

The Air Force was nonetheless encouraged by their effectiveness and evading radar detection, and gave the go ahead to produce a production aircraft designated the F-117. The use of a model number over 100 was an anachronism, and for years the public assumed the top secret stealth fighter to be designated F-19. For this reason you can find 19880’s era F-19 model kits, toys, and even a computer game.

The first F-117A rolled of the production lines in 1981. In all 64 were built through 1990, including five YF-117 prototypes, at a program cost of $111 million per plane. The production aircraft’s handling was reportedly more forgiving than its predecessors.

In addition to its reflective surfaces, the Nighthawk sported other design features now standard in stealth aircraft, including the use of radar-absorbent iron-ball paint magnetically charged so as to reduce the reflection of electromagnetic waves. The F-117’s slit-shaped exhaust ports for its F404 turbofan engines minimize the infrared signature of the exhaust. Communication antennas could be retracted to reduce radar signature, while its weapons—all two of them—were stowed in an internal bomb bay. The Nighthawk carried no radar—because the radars of the time were easily detected. Obviously, the F-117 wasn’t invisible to the eye, so it was painted black and flown exclusively at night.

Despite the “F” designation for “fighter’, the F-117 was purely a ground attack plane, without any capability to engage other aircraft in combat. Its maximum speed of 623 miles per hour meant it was slightly slower than a B-52 bomber. Its range of 1070 miles meant that it relied upon aerial-refueling—not always an easy thing to arrange for a stealth aircraft at night.

The Night Hawk’s internal weapons bays constrained it to carrying just two bombs—though to make up for that, they were generally enormous, precision-guided 2,000 pound laser-guided bombs. It could also carry BLU-109 bunker buster and GPS-guided JDAM bombs. Lacking its own radar, the F-117 relied on a thermal imager for targeting, and used GPS and inertial navigation systems.

Given these parameters, the Nighthawk had a very specific mission—to fly unseen into the heart of enemy air defenses and take out critical targets.

Lockheed did later try to market more versatile variants of the F-117 capable of operating from carriers, with more powerful F414 engines and twice the weapons load, including the ability to fire long-range AIM-120 air-to-air missiles. However, the type was rejected both by the U.S. Navy and the Royal Air Force.

Nighthawks over Baghdad and Belgrade

The first major operator of the Blackhawk was the 4450th Tactical Fighter Squadron, based in Tonopah Air Base starting in 1983. To keep the Nighthawk secret, the unit officially flew A-7 Corsair attack planes out of Nellis Air Force Base.

Shortly after entering service, the F-117 was almost deployed to bomb the Palestinian Liberation Organization in Lebanon in retaliation for the 1983 Beirut Barracks bombing that killed 220 Marines. The raid was cancelled by Defense Secretary Weinberg just 45 minutes before takeoff.

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