Part 1 - Aircraft Bombs and Pyrotechnics; Chapter 18: T.I. 250-lb.
BRITISH EXPLOSIVE ORDNANCE
Part 1 - Chapter 18
Target Identification Bombs

Introduction

Target identification bombs are designed to illuminate of mark a target for night bom-bing, but can also be used for emergency landings. Not all T.I. bombs are filled with flare candles. Some of them, such as the photoflash and sea marker T.I. bombs contain spe-cial fillings. But, because the majority of these bombs do contain candles, the following explanation is given in order to simplify the discussion of the bombs.

Three general types of candles are employed. The are the non-delay, delay, and ex-plosive candle. The non-delay candle may give illumination of various colors, as the name indicates, the candle commences to function immediately on initiation. This type of can-dle gives a sky marking effect due to the illumination given off during its fall.

The delay candle may also given illumination of various colors, but only after a period of delay, the length of which is determined by the delay unit contained in the candle.

The explosive candle is used in ground marker bombs, which contain a percentage of these candles to discourage interference with marker candles. They contain an illuminant which burns until it ignites the explosive charge. This explosive charge is also a compo-nent of the candle.

The specific types of candles are listed as follows:

Type A – These are non-delay candles of three minutes duration giing red, green, or yellow illumination.

Type B1 – These are delay candles which burn for a period of approximately two mi-nutes with a red, green, or yellow light after a delay of two and one half or five minutes.

Type B2 – These are delay candles which burn with a red, green, or yellow light. The delay and period of illumination depend upon the relative amounts of the two composi-tions.

Type B3 – These are long-delay candles which employ safety fuse to give a delay of from thirteen to thirty minutes. The candles burn with a red, green, or yellow light for approximately three minutes.

Type C – These candles burn with a red, green, or yellow light when initiated. A delay composition separating the two illuminant sections provides a delay of two and one half to eleven minutes between sections. This flare has two burning periods.

Type D – These are explosive candles which burn with a red, green, or yellow light until the explosive charge is ignited.

Type E – These are explosive candles whose illuminant is ignited by safety fuse after a delay of from fifteen to thrity-one minutes. The illuminant burns with a red, green, or yellow light for approximately two minutes, after which it ignites the explosive charge.

Type F – This is an explosive candle with two illuminant sections separated by delay composition. The delay is from two and one half to nine minutes, depending on the amount of flare composition, which burns red, green, or yellow. The second illuminant section ignites the explosive charge.

Type G – These are non-delay candles equipped with parachutes to give a skymarker effect. They provide red, green, or yellow illumination for approximately three minutes.

Type H – This is a non-delay candle, which contains alternate colored flare pellets of red and yellow, red and green, or yellow and green. Each pellet burns for approximately fifteen seconds, giving a total burning time of approximately five and one half minutes.

Type J – This is another non-delay candle containing alternate colored pellets, as well as an explosive charge. The flare burns for approximately two, three, or four minutes be-fore exploding, depending on the number of pellets it contains.

Type K – These non-delay candles are similar to and burn with the characteristic white illumination of the 4-lb. incendiary bomb, but have a different ignition system.

Type L – These are white, non-delay candles similar to the Type K, but having a steel nose containing a high explosive charge, which explodes after a delay period subsequent to the illuminant's burning out.

Type M – These are non-delay, change-color candles similar to the Type H but having a three-minute over-all burning time. The color changes are red and yellow, yellow and green, or red and green.

Type N – These are non-delay, change-color, explosive candles similar to the Type J, but having a period of illumination of two minutes and color combinations of red and yel-low, yellow and green, or red and green.

Type P – This is a delay candle which burns red, yellow, or green before exploding. The illuminating time depends on the relative quantity of delay composition and illumi-nant.

Type Q – This is a delay candle which gives a succession of white flashes of long and short duration arranged in sequence as a Morse code signal. A delay of three quarters of a minute to twenty-three minutes is provided by safety fuse.

Type R – This is a non-delay candle, which gives a succession of withe flashes of long and short duration arranged as a Morse code signal.

Red Flash Unit – This flash unit gives a red flash of short duration after a predeter-mined delay periot.

T.I. bombs are painted black over-all with a colored band around the nose plug to in-diacte flare color, and a ½-in. red filling band 8 in. from the nose. The color of the flares is also stencilled on the bomb body. A red cross near the base of the bomb indicates that explosive candles are used.

The corresponding marks of the 250-lb. bombs No. 1 - 6, 9, 10, 15, 16, 17, and 23 -28 are identical in construction and operation, differing only in the fillings. Consequently these bombs are grouped for purposes of description.

The 1,000-lb. T.I. bombs are larger versions of the 250-lb. size and correspond accor-ding to the "Number" in the designation. Thus the T.I. 1,000-lb. No. B.22 would be the enlarged equivalent of the T.I. 250-lb. No. 22 bomb.

Part 1 - Aircraft Bombs and Pyrotechnics; Chapter 18: T.I. 250-lb.