Northrop Tacit Blue

Northrop Tacit Blue
Country	USA
Role	Stealth demonstrator
First flight	February 5, 1982
Built	1

The Northrop Tacit Blue was a technology demonstrator aircraft created to demonstrate that a low-observable stealth 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.

Source: Northrop Tacit Blue on Wikipedia

Northrop Tacit Blue Walk Around
Photographers	John Heck, Vladimir Yakubov
Localisation	Unknow
Photos	64

Northrop Tacit Blue 01

Northrop Tacit Blue 02

Northrop Tacit Blue 03

Northrop Tacit Blue 04

Northrop Tacit Blue 05

Northrop Tacit Blue 06

Northrop Tacit Blue 07

Northrop Tacit Blue 08

Northrop Tacit Blue 09

Click on a photo and use the mouse scroll to view all photos

Wait, Searching Northrop Tacit Blue for you…

General Characteristics and Role

The Northrop Tacit Blue was a highly classified technology demonstrator aircraft developed by the US Air Force and DARPA during the Cold War. Nicknamed “The Whale” or “Alien School Bus” due to its unusual, bulbous shape, its main purpose was to prove that a stealthy surveillance aircraft could operate safely close to the forward line of battle. It was revolutionary for being the first stealth aircraft to successfully use curved, Gaussian surfaces to achieve a low radar cross-section, a concept later used in the B-2 Spirit bomber. It was part of the Battlefield Surveillance Aircraft, eXperimental (BSAX) program and was designed around a large Side-Looking Array Radar (SLAR) system.

Property	Typical Value (Tacit Blue)
Type	Stealth Technology Demonstrator / Surveillance Aircraft
National Origin	United States
Manufacturer	Northrop Corporation
First Flight	February 5, 1982
Crew	1 (Pilot)
Gross Weight	13,608 kg (30,000 lb)
Length	17.02 m (55 ft 10 in)
Wingspan	14.68 m (48 ft 2 in)

Powerplant and Flight Control

Engines: 2 x Garrett ATF3-6 high-bypass turbofan engines (buried in the aft fuselage to reduce heat signature).
Thrust: 24.2 kN (5,440 lbf) each.
Design Operational Speed: 460 km/h (290 mph or 250 knots).
Operating Altitude: 7,600–9,100 m (25,000–30,000 ft) (designed for loitering).
Stealth Features: Curved fuselage surfaces, V-tail, and a single flush inlet on the dorsal fuselage to minimize radar return.
Flight Stability: The aircraft was highly aerodynamically unstable, necessitating a quadruple-redundant digital fly-by-wire flight control system to keep it stable.
Armament: None; it was purely a reconnaissance testbed.

Operational History and Legacy

Status: Classified Black Project from 1982 to 1985; declassified and revealed to the public in 1996.
Flight Testing: Logged 135 test flights over three years in Area 51, Nevada.
Technology Transfer: The data gathered from the Tacit Blue was instrumental in developing two critical US Air Force aircraft:
- The Northrop B-2 Spirit stealth bomber (for its curved surface stealth technology).
- The E-8 Joint STARS surveillance aircraft (for its low-probability-of-intercept (LPI) SLAR radar technology).
Historical Significance: Tacit Blue is considered one of the most successful technology demonstrator programs in Air Force history, fundamentally changing the approach to stealth aircraft design by demonstrating the feasibility of curved stealth shaping.