Air-to-air and air-to-ground missiles are typically mounted on missile launchers that are affixed to hard points on the fuselage or wings of an aircraft. Missile launchers fall into two categories, ejection type missile launchers such as the LAU-142 manufactured by the EDO Corporation and rail missile launchers such as the LAU-127 manufactured by the Marvin Group.
A rail missile launcher or “rail launcher” generally has attachment points on top for affixing the rail launcher to the aircraft and launch rails on the bottom for mounting the missile. Launch rails have guide slots or tracks that run longitudinally along the length of the launch rails. A missile is typically loaded on a rail launcher by slidably engaging the tracks with corresponding rails, hooks, or hangers located on the missile and then sliding the missile onto the launch rails. For example, the AIM-9 series of Sidewinder missiles is loaded onto LAU-127 rail launchers by engaging “T-hangers” on the Sidewinder with tracks on the LAU-127. When the missile is launched, the missile slides forward along the tracks until it flies clear of the aircraft towards the target.
In order to prevent the missile from inadvertently sliding off the rail launcher during flight, take-off, and landing, rail launchers typically have restraint mechanisms such as stops or detents that engage corresponding stops on the missile to prevent the missile from sliding off. The detents are lowered or retracted out of the way when the missile is being loaded, unloaded, or launched from the rail launcher. Rail launchers may also have grounding mechanisms for dissipating precipitation static or P-static. P-static is created when rain, snow, hail, dust, or other particles strike the surfaces of the aircraft. If not dissipated, P-static can damage the aircraft and its electronics.
Some missions do not require an aircraft to carry missiles. During such missions the rail launchers may be empty. Empty rail launchers typically have a large flat area, sharp angles, and cavities that reflect radar signals back to the radar transmitter. This increases the radar cross section of the aircraft, making it more detectible by radar. Rail launchers may be removed when a particular mission requires an aircraft to be less detectible by radar but does not require missiles. However, some aircraft are not allowed to fly without rail launchers attached. For example, the F/A-18 Hornet fighter jet is not allowed to fly without rail launchers attached to its wingtips even if a particular mission does not require missiles. Also, current procedures for removing and re-installing rail launchers are complicated, labor intensive and time-consuming. Moreover, rail launchers can be damaged during the process of removal and re-installation.
It is known in the art that an object can be made less detectible by radar to provide “stealth” capabilities by shaping the object's surface so that radar signals striking the object are reflected away from the radar transmitter. This lowers or reduces the object's radar cross section and therefore, its detectibility by radar. One way this is done is by eliminating or reducing the number of large flat areas, cavities, and sharp angles that reflect radar signals back to the radar transmitter. This technique was used in the Lockheed Martin F-117 Nighthawk jet fighter. Unlike the large flat panels found in regular aircraft, the fuselage and wings of the F-117 Nighthawk consisted of numerous small flat panels called “facets” that were angled to deflect radar signals striking the aircraft away from the radar transmitter. Radar cross section can also be reduced by smoothing the surfaces, as long as such smoothing does not create reflections towards the radar transmitter.
Another method known in the art for reducing the radar detectibility of an object is the use of radar absorbent material or “RAM” in the manufacture of the object or to cover the object. Examples of radar absorbent materials include but are not limited to carbon, carbon fiber composites, or magnetic ferrite-based substances. Use of RAM reduces the amount of radar signals reflected back to the radar transmitter thereby reducing radar detectibility. Radar absorbent material was used by the F-117 Nighthawk, which was coated with a paint containing tiny iron balls (“iron ball paint”) that absorbed radar energy.
It can be seen from the foregoing that a need exists for a cover for an empty rail missile launcher that reduces radar detectibility, is flightworthy and easy to install and remove without causing any damage to the rail launcher. As used herein, the term “flightworthy” means that the cover meets standard requirements for allowing the cover to be used while airborne or in flight.