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a signal or illuminating rocket, used by troops for mutual identification, target indication, transmission of commands, and short-term illumination of the terrain.
Signal and illuminating rockets are identical in design and differ only by what is called the star, which contains a pyrotechnic compound appropriate to the purpose. The flare has a cardboard casing with a metal bottom and is filled with a propelling charge, the star, and wadding (for packing). The star is fired from a special flare pistol or launched by hand using the attachment on the bottom of the cartridge. It burns for five to seven seconds and has a radius of illumination of 100 m; it may project a signal, the color of which depends on the pyrotechnic compound. The rocket is visible at night for distances of up to 7 km and during the day for up to 2 km.
ii. A magnesium candle supported by a small parachute, which was at one time carried by most aircraft operating at night. This flare was fired if it became necessary to force land. The burning flare produced sufficient light to enable a pilot to see the ground for making a landing. Flares are pyrotechnic devices used for signaling or to provide illumination.
iii. A cone-shaped expansion on the end of tubing. Tubing used in aircraft fluid lines flared at an angle of 37°.
iv. Infrared flares meant to deflect incoming infrared missiles.
v. A waveguide in which one or both transverse dimensions increase toward the aperture. Also called a horn.
vi. As it relates to aerial photography, light reaching the photosensitive emulsion, resulting from internal reflections within the lens, such as occur from a noncoated air-glass lens surface.