|This article does not cite any references or sources. (November 2006)|
|Role||Concept jet fighter|
|First flight||Never flown|
|Primary user||United States Air Force|
|Number built||Never built|
Design and development
As far back as 1989 there were rumors that The Pentagon was developing a variable-sweep wing aircraft to replace the aging fleet of F-111s which were retired by the USAF in 1998. The F-111 was a medium sized bomber also capable of defending itself as a fighter and then speeding away at over 1,600 mph. In the mid-90s reports began to surface concerning a new swing-wing aircraft sighted near Cannon Air Force Base, New Mexico and at Langley Air Force Base in Virginia. In September 1994, that aircraft was observed circling high over Amarillo, Texas for several minutes at midday.[dubious ] The plane was not a standard variable swing-wing aircraft as first reported, rather employing a unique forward-swept swing wing mechanism that enables the jet to become an advanced attack aircraft capable of precision weapons delivery, super maneuverability (for air combat) and Mach 3 "dash" capability. It is a bomber, fighter and high-speed aircraft all-in-one.
For a time it was concluded that this top-secret project by Northrop was officially named Bird of Prey on account of the squadron patch worn by pilots involved in the covert BoP project, though it is now known that the Bird of Prey was another Black project stealth aircraft altogether, by Boeing. It is possible that this ATF/B -type "Switchblade" craft is a stealth concept plane from back in the Multi-Role Fighter [MRF] competition days, given its aptitude. Multi-mission aircraft of the past have invariably had to make design sacrifices in one area or another, never really coming close to becoming true flying Swiss Army knives. The Northrop design seems to meets all the design criteria for an advanced multi-regime tactical bomber/fighter aircraft. Northrop Grumman have considerable expertise in designing advanced aircraft. Northrop was the chief contractor on the stealth B-2 Spirit, the YF-23 Black Widow II and the Tacit Blue. Grumman has experience designing forward swept wing and variable-swept wing aircraft, the X-29 and F-14 Tomcat, respectively.
The wings are attached to the fuselage (body) at a pivot point toward the rear of the aircraft. With the wings fully swept aft the aircraft can slow to drop precision weapons or land on short unimproved runways. Swept forward twenty degrees and the aircraft takes advantage of the maneuverability that forward-swept wings offer becoming a highly agile air combat platform. Sweep the wings fully forward and they become flush with the aircraft with the trailing edge becoming the leading edge, forming a highly swept 75-degree stealthy delta ideal for high-speed Mach 3 exits. Or as it is understated in the U.S. Patent 5,984231 abstract, "the aforementioned apparatus may be used in a method to configure the aircraft for flight in a desired flight regime".
|Wings fully extended||Long wingspan increases lift, enabling slower flight speeds for precision bombing and
landing on short runways.
|Wings swept forward||Forward sweep provides a good balance of lift and drag; efficient airflow over the wings
and control surfaces enhances the fighter's maneuverability for air-to-air combat.
|Wings fully swept||Low aspect ratio provides the least drag, enabling the aircraft to speed up to Mach 3. In
this configuration the trailing edge becomes the leading edge, a section of the wing root
becomes the new trailing edge.
||This section possibly contains original research. (April 2008)|
Though the concept of the "Switchblade" is extremely good for different combat situations, the mechanism that would be used to operate the wings would be quite heavy and bulky, and would have to be placed very close to the middle of the plane in order to aid balance of center of gravity. Fly-by-wire may compensate for these problems but the aircraft must still keep from being too unstable because computers are unable to compensate for too radical a problem.
Additionally, when the wings are at their fully swept angle, the wing shape presented to the oncoming air will not be a proper airfoil [aerofoil] shape, creating an inconsistent one which increases drag with negative effects on speed and control. The shape presented would be an airfoil (from the canard) plus the side cross section of the wing. This would encourage very small wings. Flat plate airfoils are one possible solution, but they are not a perfect solution, given their easier stall, higher drag and smaller lift. Wings with adaptable surfaces are one possible way of resolving problems.
The fictional F/A-37 Talon (shown), which starred in the 2005 film Stealth, had the "Switchblade's" swing-wing design. The Talon was capable of at least Mach 4, and used a pair of scramjets/pulse detonation engines for all flight speeds from subsonic to hypersonic.
Also in the 2002 film I-Spy (film), there is a plane which looks incredibly similar to the Northrop Switchblade and is called "Switchblade" or "the Switchblade" (though Eddie Murphy's character calls it "The Leafy Bug"), it has the technology to turn invisible.
The designers of Ace Combat incorporated the design into the similar X-02 Wyvern, an experimental fighter which has featured in Ace Combat 04: Shattered Skies, Ace Combat 5: The Unsung War, Ace Combat Zero: The Belkan War and Ace Combat X: Skies of Deception.