NVAHOF VIRTUAL MUSEUM
TACIT BLUE
Groom Lake, Nevada – Declassified 1996
The Northrop Tacit Blue was a technology demonstrator aircraft created to demonstrate that a stealth low observable surveillance aircraft with a low probability of intercept radar and other sensors could operate close to the forward line of battle with a high degree of survivability.
Unveiled by the U.S. Air Force on 30 April 1996, the Tacit Blue Technology Demonstration Program was designed to prove that such an aircraft could continuously monitor the ground situation deep behind the battlefield and provide targeting information in real-time to a ground command center. Tacit Blue represented the ‘black’ component in the larger Assault Breaker program, which intended to validate the concept of massed standoff attacks on advancing armoured formations using smart munitions. The Pave Mover radar demonstrators provided the non-stealthy portion of the program’s targeting system, whereas Tacit Blue was intended to demonstrate a similar but stealthy capability, while validating a number of innovative stealth technology advances.
Tacit Blue, nicknamed “the whale,” featured a straight tapered wing with a V-tail mounted on an oversized fuselage with a curved shape. A single flush inlet on the top of the fuselage provided air to two high-bypass turbofan engines. Tacit Blue employed a quadruply redundant, digital, fly-by-wire flight control system to help stabilize the aircraft about its longitudinal and directional axes.
The sensor technology developed for Tacit Blue is now being used by the E-8 Joint STARS aircraft.
A Northrop engineer described the Tacit Blue a being an aircraft that at the time was arguably the most unstable aircraft man had ever flown.”
The aircraft made its first flight at Groom Lake, Nevada in February 1982, and subsequently logged 135 flights over a three year period. As Northrop chief test pilot, Richard G. “Dick” Thomas led the flight-testing of TACIT BLUE one-of-a-kind demonstrator. He flew the first flight of TACIT BLUE at Groom Lake, Nevada, on 5 February 1982 and piloted 70 of the airplane’s 135 flights. According to the U.S. Air Force, TACIT BLUE was one of the most successful high-technology demonstrator programs ever conducted. It had a direct influence on the design of the B-2 stealth bomber including development of the flight control system, low observables shaping and materials, propulsion installation, and electronic systems. The aircraft often flew three to four flights weekly and several times flew more than once a day, reaching about 250 flight hours. Carried out in total secrecy, the TACIT BLUE program was not declassified until 1996 when the airplane was publicly unveiled at the U.S. Air Force Museum (now National Museum of the U.S. Air Force) at Wright-Patterson Air Force Base, Ohio.
Specifications for the Tacit Blue are:
General characteristics
* Crew: 1
* Length: 55 ft 10 in (17 m)
* Wingspan: 48 ft 2 in (14.7 m)
* Height: 10 ft 7 in (3.2 m)
* Loaded weight: 30,000 lb (13,606 kg)
* Powerplant: 2x Garrett ATF3-6 high-bypass turbofans, 5,440 lbf (24 kN) each
Performance
* Maximum speed: 287 mph (461.88 km/h)
* Service ceiling: 30,000 ft (9,144 m)
* Thrust/weight: 0.36