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The rocket with warhead, flare, M257, is fired from helicopter with standard 2.75-in. motor MK40 or MK66 to attain elevation between 2000 and 4000 ft at 3000 m downrange, Upon rocket launch, the M442 fuze arms upon acceleration (17 Gs approximately required ). After 1.5 seconds (at motor burnout), the fuze functions initiating delay train, After nine seconds, delay ignites first expulsion charge in fuze assembly. Gas pressure forces pusher plate forward, shears pin. separates motor and adapter section from remainder of warhead. Rocket velocity is now 800 fps approximately.
The deflector plate, attached by cable to motor adapter, is extended into airstream, deflects path of motor and adapter. Pusher plate, attached to drogue chute, deploys drogue, Rocket warhead velocity then decreases to 200 fps, approximately, during the next two seconds.
Upon deployment of drogue chute, the gas generator is activated by pull on lanyard attached to drogue. After two seconds, tile gas generator functions the second expulsion charge located in retainer block of drogue housing. Gas pressure forces pusher plate forward, shearing pins and separating drogue housing from main chute insert and candle assembly,
The pusher plate is attached by a threadline to the pilot chute. The pilot chute is deployed, and, in turn, pulls bag off main chute. The main chute now deploys the steel cable which is attached to the main chute shroud lines on one end, and, in turn, pulls a lanyard attached to candle igniter assembly.
The pull on the lanyard rotates a bellcrank, releasing the firing pin. The firing pin fires a rifle primer, which fires boron pellets. The boron pellets ignite a propellant wafer. Propellant ignites the candle. Ignition gases pressurize nose cap, blowing it free.
The candle, suspended from the main chute, is now burning. During the first 15 seconds, the igniter housing is burned away, The candle descends at 15 fps, burns for 100 seconds with a minimum light output of one million candle power (CP).
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