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The U.S. Navy has patented technology to create mid-air images to fool infrared and other sensors. This builds on many years of laser-plasma research and offers a game-changing method of protecting aircraft from heat-seeking missiles. It may also provide a clue about the source of some recent UFO sightings by military aircraft. The U.S. developed the first Sidewinder heat-seeking missile back in the 1950’s, and the latest AIM-9X version is still in frontline service around the world. This type of sensor works so well because hot jet engines exhausts shine out like beacons in the infrared, making them easy targets. Pilots under attack can eject decoy flares to lure a missile away from the launch aircraft, but these only provide a few seconds protection. More recently laser infrared countermeasures have been fielded which dazzle the infrared seeker. A sufficiently intense laser pulse can ionize producing a burst of glowing plasma. The Laser Induced Plasma Effects program uses single plasma bursts as flash-bang stun grenades; a rapid series of such pluses can even be modulated to transmit a spoken message (video here). In 2011 Japanese company Burton Inc demonstrated a rudimentary system that created moving 3D images in mid-air with a series of rapidly-generated plasma dots (video here). A more sophisticated approach uses an intense, ultra-short, self-focusing laser pulse to create a glowing filament or channel of plasma, an effect discovered in the 1990s. Known as laser-induced plasma filaments (LIPF) these can be created at some distance from the laser for tens or hundreds of meters. Because LIPFs conduct electricity, they have been investigated as a means of triggering lightning or creating a lightning gun. US Army 'lighting gun' experiment with laser-generated plasma channel One of the interesting things about LIPFs is that with suitable tuning they can emit light of any wavelength: visible, infrared, ultraviolet or even terahertz waves. This technology underlies the Navy project, which uses LIPFs to create phantom images with infrared emissions to fool heat-seeking missiles. The Navy declined to discuss the project, but the work is described in a 2018 patent: “wherein a laser source is mounted on the back of the air vehicle, and wherein the laser source is configured to create a laser-induced plasma, and wherein the laser-induced plasma acts as a decoy for an incoming threat to the air vehicle.” The patent goes on to explain that the laser creates a series of mid-air plasma columns, which form a 2D or 3D image by a process of raster scanning, similar to the way old-style cathode ray TVs sets display a picture. A single decoy halves the chances of an incoming missile picking the right target, but there is no reason to stop at one : “There can be multiple laser systems mounted on the back of the air vehicle with each laser system generating a ‘ghost image’ such that there would appear to be multiple air vehicles present.” Unlike flares, the LIPF decoy can be created instantly at any desired distance from the aircraft, and can be moved around at will. Equally importantly, moves with the aircraft, rather than dropping away rapidly like a flare, providing protection for as long as needed. The aircraft carrying the laser projector could also project decoys to cover other targets: “The potential applications of this LIP flare/decoy can be expanded, such as using a helicopter deploying flares to protect a battleship, or using this method to cover and protect a whole battle-group of ships, a military base or an entire city.” The lead researcher in the patent is Alexandru Hening. A 2017 piece in the Navy’s own IT magazine says that Dr. Hening has been working on laser-induced plasma at Space and Naval Warfare Systems Center Pacific since 2012. “If you have a very short pulse you can generate a filament, and in the air that can propagate for hundreds of meters, and maybe with the next generation of lasers you could produce a filament of even a mile,” Dr. Henning told the magazine, indicating that it should be possible to create phantoms at considerable distances. Phantom aircraft that can move around at high speed and appear on thermal imagers may ring some bells. After months of debate, in April the Navy officially released infra-red videos of UFOs encountered by their pilots, although the Pentagon prefers to call them “unidentified aerial phenomena.” The objects in the videos appear to make sudden movements impossible for physical aircraft, rotate mid-air and zip along at phenomenal speed: all maneuvers which would be easy to reproduce with a phantom projected image. It is unlikely the Pentagon would release videos of their own secret weapon in a bizarre double bluff. But other nations may have their own version. In the early 1990s the Russians claimed that they could produce glowing ‘plasmoids’ at high altitude using high-power microwave or laser beams; these were intended to disrupt the flight of ballistic missiles, an answer to the planned American ‘Star Wars’. Nothing came of the project, but the technology may have been refined for other applications in the subsequent decades. Heat-seeking missiles will no doubt evolve ways to distinguish the plasma ghosts from real jets, leading to further refinement of the decoy technology, and so on. Whether humans also get smart enough to recognize such fakes remains to be seen.