The sensitive type detonators are employed with pistols having needle strikers in bombs which sensitive type initiation of the explosive train is desired.

Sensitive type detonators differ from the anvil type in that no percussion cap and anvil are provided, and they are made to a standard length of approximately 3.5 inches. Hence, they are interchangeable in sercive bombs, and are selected according to the delay incorporated in them.

They may be identified by the stem, which is painted green for a lenght of 1 inch from the closed end, and by a green label secured to the detonator plug with shellac and varnished over.

The lower portion of the stem contains a quantity of detonating composition, usually A.S.A. mixture and C.E. In delay detonators, the upper portion of the stem accommo-dates a sleeve which contains a quantity of delay composition, the sleeve being retain-ed in position by the detonator plug. The initiating detonator consits of a small metal cup having a flash hole through its base, this hole being covered by a thin disc, abobe which is a small charge of cap composition covered by a metal disc, a paper disc secu-red with shellac, and a metal washer, which are held in position by lugs turned inwards from the rim of the cup on the washer.

On impact of the fuzed bomb with the target, the pistol striker pierces the initiating detonator and fires the cap composition, which in instantaneous detonators fires the detonating composition in the stem, or, in delay detonators fires the detonating compo-sition in the sleeve, which in turn fires the detonating composition in the stem.

Detonators

Color on Head

Delay

No. 39 Mk I

Yellow

No. 39 Mk II

Yellow

No. 46 Mk I

Green

No. 48 Mk I

Red

No. 50 Mk I

Brown

No. 51 Mk I

Black

No. 52 Mk I

White

No. 53 Mk I

Aluminum

No. 54 Mk I

Grey

No. 55 Mk I

Blue

No. 56 Mk I

White and Red

No. 57 Mk I

Blue & Yellow

20 lb. AIRCRAFT BOMB Mk II & III (Obsolete)

This detonator is in a class by itself being a form of detonator and exploder combi-ned. The explosive in it consists of a percussion cap, 45 grains of 80/20 fulminate com-position, and C.E. It has no delay, and is approx. 2.2" in length.

AIRCRAFT BOMB, 45 GRAIN, No. 1 Mk I

Certain bombs are fitted with a central tube for containing exploders and two of more detonators, in order to provide complete and simultaneous detonation of the whole of the main filling. This detonator is inserted in an exploder of bombs of this type, and is fired by another detonator since it does not contain its own initiator. It has no delay, is 3.1 inches in length and has a filling of 45 grains of 80/20 fulminate composi-tion. It is used in bombs R.L. 112 lb., Mks VII and VIIC; G.P. 250 lb., Mks I, II and III; and G.P. 500 lb., Mk V.