Laser sources for medium caliber cannon ignition

Medium caliber cannons, such as the Army's M230 chain gun, currently utilize a high current electrical pulse to initiate the propellant. While electrical ignition is reliable, electrical based primers are susceptible to premature ignition from EMI, EMP, or other stray or directed electromagnetic sources. Laser ignition of medium-caliber cannon systems has several advantages over the current electrically initiated ignition system. In addition to removing hazards due to electrostatic or radiated electromagnetic energy, lasers are an ideal ignition source for new primer compounds, such as Metastable Intermolecular Composites (MIC), that are potentially environmentally friendly replacements for lead styphnate containing compounds. This paper will describe our efforts to develop a laser source suitable for the M230 medium-caliber automatic cannon as used on the Apache AH-64 helicopter. We will describe early proof of concept laser systems including a fiberoptic-coupled flashlamp-pumped Nd:YAG source, direct Nd:YAG laser sources, and a full rate of fire demonstration laser that was mounted directly on the M230 housing. We will also discuss our plans and designs for a direct semiconductor laser ignition source for the M230.