Flare

flare

1. Optics

a. the unwanted light reaching the image region of an optical device by reflections inside the instrument, etc.

b. the fogged area formed on a negative by such reflections

2. Astronomy short for solar flare

3. Aeronautics the final transition phase of an aircraft landing, from the steady descent path to touchdown

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flare [fler]

(aerospace engineering)

To descend in a smooth curve, making a transition from a relatively steep descent to a direction substantially parallel to the surface, when landing an aircraft.

(astronomy)

A bright eruption from the sun's chromosphere; flares may appear within minutes and fade within an hour, cover a wide range of intensity and size, and tend to occur between sunspots or over their penumbrae.

(chemical engineering)

A device for disposing of combustible gases from refining or chemical processes by burning in the open, in contrast to combustion in a furnace or closed vessel or chamber.

(design engineering)

An expansion at the end of a cylindrical body, as at the base of a rocket.

(electronics)

A radar screen target indication having an enlarged and distorted shape due to excessive brightness.

(electromagnetism)

horn antenna

(engineering)

A pyrotechnic item designed to produce a single source of intense light for such purposes as target or airfield illumination.

(naval architecture)

A concave curve of a boat's or ship's sides away from the center line, above the waterline, normally at the bow.

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Flare 

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.