FUZING

COLOR & MARKINGS

OVERALL LENGTH

MAX. BODY DIAMETER

TOTAL WEIGHT

ILLUMINATING TIME

0.1 sec. approx.

DESCRIPTION:

The Mk I and II flashes are similarly constructed, the only difference being that the Mk II has narrower tail fins. Each flash has a tubular body, closed at the tail by a clos-ing dome and at the nose by a front diaphragm having a bush into which is screwed the nose fuze. The four tail fins are located at the tail end. A quantity of flash composition closed by a press-cap and overseal. A central tube, closed at each end, extends be-tween the front and rear diaphragms and is filled with gunpowder. A socket secured to the front diaphragm houses a perforated disc and a muslin disc which closes the nose end of the central tube. The perforated disc is held in position by a socket plug having a flash hole covered by a disc which, in earlier issues, is of brass, but in later issues is paper.

SUSPENSION:

Suspended by means of a suspension band to wich are secured two suspension lugs, one for attaching to a Light Series bomb carrier the other attaching to a Universal bomb carrier.

FUNCTIONING:

When the fuzed flare is released "live" from the aircraft, the fuze is set in operation, and the flare falls freely until the magazine charge explodes. The flash from the charge passes through the flash hole in the diaphragm and ignites the powder puff.

The gases formed by the burning of the gunpowder in the puff exert pressure on the under side of the perforated disc, forcing the candle unit toward the closing disc so that the wooden slats push off the dome. The candle unit and parachute are ejected from the flare body, which falls away along with the expended fuze. The flash from the puff passes through the holes in the perforated disc to ignite the primed cambric disc and the gunpowder at the nose of the candle. The gunpowder ignites the priming com-position, which in turn ignites the incendiary composition. As the incendiary composition burns, the magnesium alloy candle body also burns, and pieces of the burning candle fall away, giving the appearance of a vertical chain of white lights in the sky.

REMARKS:

1. These flares are similar in external appearance to the Mk IV 4.5" Reconnaissance Flare (see external on page 116).

2. Mk II Flare: This flare is similar to the Mk I, except that just below its lid, the candle unit is provided with a container filled with gunpowder. This gunpowder is ignited by the incendiary composition and ejects any magnesium alloy which remains in the candle unit when the incendiary composition is expended. This insures that odd pieces of burning magnesium alloy do not continue to fall after the flare has served its pur-pose.

3. Mk III Flare: This flare is identical to the Mk II, except that the burning time has been increased to 120 secs. by use of a different type of incendiary composition and of a steel container and magnesium alloy candle body which are 3" longer than those in the Mk II Flare. The increased length of the candle unit is accommodated by reducing the space occupied by the parachute.