Few programs in the shadowy corridors of military aviation history have retained an air of mystery and innovation rivaling the YF-118G Bird of Prey. As a stealth technology demonstrator developed by McDonnell Douglas’ secret branch, known as the Phantom Works, throughout the 1990s, its existence was as classically clandestine as Area 51. Unlike most stealth programs, though, the Bird of Prey wasn’t intended to make its way into service. Rather, it acted like a testbed for many of the ground-breaking design and manufacturing processes still in use today within modern stealth aircraft.
It was called the Bird of Prey, and its name came from the Klingon spacecraft in Star Trek. The Bird of Prey epitomized chutzpah and ingenuity. Most stealth programs have full-body counts in terms of cost; this one flew over Area 51 for less than the cost of a single F-35 today. That was due to a combination of rapid prototyping, advanced composite structures, and off-the-shelf components.
The real beginning of the stealth revolution was the Lockheed F-117 Nighthawk, which secretly entered service in October 1983. Although an attack aircraft rather than a fighter, its radar cross-section measured only 0.11 inches; thus, as such, it was nearly undetectable to enemy radar. The success of the Nighthawk would become one of those defining moments that proved a change in aviation technology and a shift in air warfare doctrine.
Less than a decade later, while Lockheed’s YF-22 battled Northrop’s YF-23 for the Air Force’s Advanced Tactical Fighter contract, McDonnell Douglas’ Phantom Works had stealth ambitions all their own. They hired veteran of Lockheed’s Skunk Works Alan Wiechman to lead their efforts. Wiechman had been part of the Have Blue program, working on the F-117 Nighthawk stealth fighter and the Sea Shadow stealth warship.
Work began on the YF-118G in 1992, and Wiechman decided to make use of rapid prototyping. Wiechmann’s ingenuity resulted in using computers to simulate performance, where he could create prototype parts that were much closer to real components. This, along with single-piece composite structures, helped to avoid the use of body panel seams where stealth could be compromised.
In addition to this, off-the-shelf components used for many aspects of the Bird of Prey’s build helped it to stay within budget. Its Pratt & Whitney JT15D-5C turbofan engine, cranking out a mere 3,190 pounds of thrust, was better suited to powering a Cessna business jet. The ejection seat was lifted from an AV-8B Harrier, the control stick and throttle from an F/A-18 Hornet, and the rudder pedals from an A-4 Skyhawk. As Air Force Test pilot Colonel Doug Benjamin quipped, “The clock was from Wal-Mart, and the environmental control system was essentially a hairdryer.”
They had a flyable prototype by 1996. It was on September 11, 1996, that the Bird of Prey, powered by a single 2,900-pound thrust F118-101 engine buried in its fuselage, took to the skies over Groom Lake, with an angular gull-shaped wing and tailless design—an initial drag-prone and stability-challenged concept. Still, it had clocked up 38 successful flights by 1999. With a cruising speed of only 300 miles per hour and a maximum operational ceiling of 20,000 feet, the real success of the Bird of Prey was its stealth capabilities.
The team at Phantom Works had proven they could build a stealth aircraft for less than $67 million–a fraction of the cost of a fleet of modern stealth fighters. When this is adjusted for inflation, it becomes something in the order of $111 million today, less than the cost of a single F-35B. The Bird of Prey’s legacy lives on in design and production techniques that pioneered, further going on to shape the future of stealth aviation.