Stealth aircraft are designed to avoid detection using a variety of technologies (collectively known as ‘stealth technology’) that lower emission of radar, infrared light, light which is visible to the eye, radio-frequency, and to reduce sound. The U.S. military has adopted and utilized four stealth aircraft designs: the F-117 Nighthawk, the B-2 Spirit, the F-22 Raptor, and most recently, the F-35 Lightning II, designed by Lockheed Martin.
Experiments to decrease the probability of an aircraft’s detection have been taking place since WWI, with the German military’s (failed) attempt to introduce a material called Cellon (Cellulose acetate) as an aircraft covering to reduce its visibility. During WWII, Nazi Germany experimented with using a carbon-impregnated plywood resin as a bonding agent for its Horten Ho 229 flying wing fighter bomber, in an attempt to absorb radio waves. The experiments leading up to the development of modern stealth technology were not possible until the 1970’s and that was made possible by advances in the field of computer technology. The first official combat use of stealth aircraft was not until Operation Just Cause in Panama in December of 1989.
Even with modern-day advances in computers and technology it is still impossible to make an aircraft completely undetectable by radar, but stealth technology makes it more difficult for conventional radar to locate or track the aircraft. This effectively increases the odds of an aircraft successfully avoiding detection by enemy radar and/or avoiding being successfully targeted by radar-guided weapons. Stealth aircraft are created using a complex design philosophy with the ultimate goal of reducing the ability of an opponent’s sensors to detect, track, or attack the stealth aircraft. This design planning method also takes into consideration the heat, sound, and other emissions of the aircraft since these can also be used to locate it. Stealth aircraft are extraordinarily more expensive to develop and manufacture than regular aircraft. The U.S. Air Force spent almost $105 billion on the B-2 program, for example.
While other countries like The People’s Republic of China and Russia are known to be testing their versions of stealth aircraft, the only country to have used stealth aircraft in combat is the United States. The US has deployed stealth aircraft during their invasion of Panama, the first Gulf War, the Kosovo Conflict, the War in Afghanistan, the War in Iraq and the 2011 military intervention in Libya.
During the May 2011 operation to kill Osama bin Laden, one of the helicopters which was used to secretly transport US soldiers into Pakistan crashed into the bin Laden compound. After the wreckage was analyzed, it was revealed this helicopter had stealth-characteristics, making this the first publicized operational use of a stealth helicopter.
Stealth aircraft will continue to play a valuable role in military air combat with the United States currently using the F-22 Raptor, the B-2 Spirit, and the F-35 Lightning II to perform a variety of missions. In September 2014, as part of the coalition to defeat ISIS, the US debuted the combat use of the F-22, flying it over Syria.