Accession Number : AD0771919

Title :   Measurement of Spin Decay and Instability of Liquid-Filled Projectiles via Telemetry.

Descriptive Note : Memorandum rept.,

Corporate Author : BALLISTIC RESEARCH LABS ABERDEEN PROVING GROUND MD

Personal Author(s) : Mark,Andrew ; Mermagen,William H.

Report Date : OCT 1973

Pagination or Media Count : 33

Abstract : The spin history and instability of projectiles containing a right circular cylinder filled with a liquid are determined over long flight paths. Based on past experience, stability or instability is achieved simply by adjusting the volumetric fill within the cylinder. The motion of the projectile is determined by judiciously placing photovoltaic cells behind narrow slits in the ogive portion of the projectile and sensing its orientation with respect to the sun. The cell outputs are amplified and used to drive a subcarrier oscillator which in turn modulates a P-band radio frequency oscillator. The result is transmitted to ground and recorded on tape. The spin history of a liquid-filled projectile is significantly different from a physically identical but dry projectile. Instability is indicated during the spin-up phase of the liquid motion. (Author)

Descriptors :   *SPIN STABILIZED AMMUNITION, STABILITY, TELEMETER SYSTEMS, LIQUIDS, PROJECTILES, SPIN STABILIZATION, PROJECTILE TRAJECTORIES, DECAY, RATES

Subject Categories : Ammunition and Explosives
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE