An experimental laser ignition system has been developed for the M230 cannon used on the Apache helicopter. This high-rate of fire (625 rounds/minute) chain gun provided many design challenges including a complex optical path, limited available space, high levels of shock and vibration and a maximum allowable cartridge functioning time of 4 ms. In order to satisfy this time limit with laser ignition, a subprogram was developed to explore laser sensitive, fast-acting energetic materials with good ignition transfer properties. Annual consumption rates in excess of 500,000 rounds per year in training dictated that ultimate ammunition production costs be considered in all design alternatives. Environmentally benign ("green") materials are being required by federal and state environmental regulations and standards and were factored into the new optical ignition system design. Both newly developed nano energetics and other pyrotechnic materials have been explored to fill this requirement. The development of the system and components is described in this paper from the firing of Mann barrel (single shot) fixtures to optimize cartridge performance, single-shot firing of the cannon using fiber-optic and optical-train light paths, culminating in a demonstration firing of the automatic cannon at its full rate of fire for a 10-round burst. The remaining technical challenges and future direction of the program are presented.
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