Development aspects of cable cutter cartridge for helicopter application

This research work emphasizes on the development aspects of a cartridge cable cutter for helicopter application. This cartridge is used to rescue hoist system during emergency for helicopter application under adverse conditions. It is an electrically initiated cartridge in which two electrical squibs are used with specified current and voltage. As the cartridge is initiated, the squib gets incandescent and initiates an explosive train. A cartridge cable cutter is a propellant actuated device (PAD) that generates hot combustion gases having high temperature and pressure on burning of gun powder and propellant inside the cartridge case. The cable cutter cartridge under study is filled with energetic materials (EM) such as propellants and gun powder. It releases the energy very quickly which acts on the projectile i.e. the cutter in actual system. A projectile velocity measurement was carried out using Doppler RADAR (radio detection and ranging). To assess the projectile velocity is the unique design feature in armament field. It is responsible for the measurement of the projectile velocity at the muzzle end of velocity test rig (VTR). The minimum and maximum projectile velocities were experimentally measured in between 70 ms−1 and 150 ms−1. The projectile velocity measurement is an evaluation methodology as performance parameter of this cartridge. The cartridge under study has been developed meeting structural, functional and mechanical requirements. The cartridge has undergone various exhaustive qualification tests during development phase. The cartridge was thus designed, qualified and validated through rigorous development trials. The main objective of this article is to address development aspects of the cartridge cable cutter for helicopter application. In conclusion, after successful design, development and qualification trials, the cartridge was found to meet all the functional and operational requirements considering the end use.