|Tacit Blue Stealth Observation Aircraft at National Museum of the U.S. Air Force, near Dayton Ohio. Photo Credit: Vijainder K Thakur|
The program aimed to develop a single-seat jet for battlefield surveillance was declassified in 1996. (I took the photo above in 2004 during a visit to the AF Museum with my family. My wife and daughter can be seen on the far right in the foreground.)
Only one and a half copies of the aircraft were built, the half being a backup that could be built upon if the one were to crash. The aircraft flew 135 sorties.
The rather odd shape of the aircraft, which resembled an inverted bath tub, earned it the nickname of Whale.
One of the test pilots who flew the aircraft, Ken Dyson, told CNN, "The airplane flew pretty solid, I'd say."
Tacit Blue was used to validate the ability of curved surfaces to deflect radar waves and facilitated development of the B-2 Spirit Bomber.