Fuze Extension M1:

The fuze extension, M1, may be used in any bomb adapted for the AN-M103 nose fuze. It comes in 6, 9, 12, 18, 24, 30 and 36 inch sizes, and consists of a burster sup-port and a burster assembly. The burster support is a steel tube 2.375 inches outside diameter which has a male thread at one end and a female thread at the other. The for-mer screws into the adapter in the nose of the bomb; the latter receive the AN-M103 nose fuze. The burster assembly consists of an asphalt-impregnated, chipboard tube which has a reces-sed metal cap crimped to one end and a plain metal cap cemented to the other. The tube is filled with cast tetrytol. A shakeproof lock washer is supplied with each assembly.

To assemble the extension, proced as follows:

(1) Remove fuze hole plug of the bomb and inspect.

(2) Place the lock washer on the booster support and screw the support into the nose fuze adapter. Be sure it is tight enough for the lock washer to take hold.

(3) Insert the burster, crimped end first, into the support and push it in as far as pos-sible. Do not use force. If the burster binds, inspect to see whether the support or the burster is at fault and discard the faulty item.

Arming Wires:

The Navy is now procuring four standard arming wires for all bombs now in naval use, replacing the varied types previously in service. They will fit any bomb up to and includ-ing 2000 lbs., and by adding an arming wire extension which is part of the new system can be used in bombs up to 4000 lbs.

The new wires come straight and are packed in hermetically sealed metal tubes, pro-tecting them from corrosion. Depending on type, the tube contain from 50 to 100 wires, including their clips and extra clips. The wires are cut when installed to fit the bomb.

Mk 1 Arming Wire

The Mk 1 arming wire is a single strand bronze wire, 57" long and .064" in diameter, joined to w swival and loop. This assembly can be used on all bombs expended with a single fuze up to and including 2000 lb. bombs. Buord recommends using two of these Mk 1 assemblies to rig out the athwartships hydrostatic fuzes of depth bombs. On hund-red Mk 1 arming wires together with 300 safety clips are packed in an airtight metal tube, (inclu-des an extra clip for each wire).

Mk 1 Arming Wire Extension

The Mk 1 arming wire extension is a flexible steel cable 16" long and .0625" in diame-ter. It incorporates a swivel loop arrangement and a brass spring clip. The Mk 1 arming wire extension may be used with two Mk 1 arming wires to install arming for the 4000 lb. light case bomb. In addition, it is used to lengthen wires on fragmentation or incendiary clusters. One hundred of these extension wires are packed in an air-tight metal tube.

Mk 2 Arming Wire

The Mk 2 arming wire is a double strand bronze wire of the same type, diameter and length as the Mk 1 arming wire. It is used on all bombs expended with a nose and tail fuze up to and including 2000 lb. bombs. Fifty Mk 2 wires together with 300 safety clips are packed in an air-tight metal tube.

Mk 3 Arming Wire

The Mk 3 arming wire is a single strand steel wire 57" long and .033 in diameter. The Mk 3 arming wire can be used anywhere the .036 diameter Navy-type wire was used, and in addition can be used in all M111A2 jump-out pin tpye fuzes in which a stronger wire is needed. One hundred Mk 3 arming wires together with 100 safety clips are packed in an air-tight metal tube.

The new standard assemblies do not replace special assemblies on any clusters either fragmentation or incendiary but the Mk 1 wire extension is used with such clusters so that their wires which are too short for proper fitting can be connected.

Arming wires are subjected to considerable wear from vibration. For that reason, tub-es are supplied to protect a wire at its point of maximum wear. Use of these tubes on all bombs equipped with arming wire brackets is mandatory. All old AN-type arming wires on hand and pre-cut to length for a bomb should be returned to the Army.