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

Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

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.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.

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.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

flare

i. A maneuver carried out just before touchdown to reduce the rate of descent, so that the aircraft settles on the runway smoothly and with the least amount of vertical speed. Normally referred to as flare-out.
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.

An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved