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ROCKET, FLECHETTE, 2.75-INCH, WDU-4A/A |
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Filler and Weight | ||
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| 20-grain flechettes, | |||
| Body and Overall Weight | |||
| Extruded aluminum, 9.3 lb | |||
| Color | |||
| Olive drab w/white markings | |||
| Type of Round, DODIC | |||
| Antipersonnel, 1340-H459 |
| Description: |
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| The complete round consists of a warhead with an integral fuze and rocket motor. The warhead consists of 3 main parts: a nose section, a body, and an integral fuze. The nose section, a plastic cone bonded to a metal plate, is attached to the body by shear pins. The body is a hollow cylinder loaded with 20 grain flechettes. The most recently manufactured WDU-4A/A warheads contain three tracers for the purpose of assisting the pilot/gunner in identifing the beaten zone of the flechette impact pattern. Two semicylindrical sleeves retain the flechettes in place. A metal pusher plate is located just aft of the flechettes. The threaded end of the body is machined internally to accommodate a base-detonating (BD) fuze. c. The low-spin folding-fin aircraft rocket (LSFFAR) is an air-to-ground rocket primarily deployed from rotarywing and other low-speed aircraft. However, it is also used on Air Force and Navy jet aircraft restricted single in ripple fire and in a fire mode. The Mk 40 Mods 1 and 3 have integral bulkhead motor tubes whereas the Mk 40 Mod 0 has nonintegral bulkhead tube. The igniter of the Mod 3 motor differs from that of the Mods 0 and 1 motors in that the igniter has been modified to incorporate a carried, frangible case in lieu of the blowout plug. Also, the squib is located on the periphery instead of the center of the case. |
| Use: |
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| The warhead contains used against personnel. |
| Functioning: |
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| a. The rocket motor functions when current passes through the launcher firing contact to the igniter in the rocket motor. This current generates the heat necessary to initiate the igniter charge which ignites the propellant grain. Combustion gases from the burning propellant pressurizes the chamber and exhaust through the nozzle, providing the unequal forces required for rocket thrust. b. Functioning of the fuze sets off an expelling charge which forces the pusher plate, flechettes and semicylindrical sleeves forward. This shears the pins attaching the nose cone to the body and expels the flechettes into the slipstream ahead of the rocket. |
| Munition Components: |
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| Data Source: |
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| TM 43-0001-30 Dec 1981 |
| Munitions Tech Data Sheet: |
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