Editing Project HARP (section)

==== Martlet 4 Control Systems ====
A guidance and control system were developed for the orbital mission by Aviation Electric Limited of Montreal under the direction of McGill-BRL-Harry Diamond Laboratory group. [[Infrared]] horizon sensors and sun sensors were included in calculating [[Spacecraft attitude control|vehicle attitude]]. Information for on-board sensors was to be processed by the logic module, which provided commands to a cold gas thruster system which in turn adjusted the vehicle's orientation. The components of the guidance and control assembly were integrated into a 6.25-inch diameter test projectile. Sun sensors, horizon sensors, telemetry packs, receiving/transmitting antenna, hydraulic systems, logic modules, and gas thruster [[Spacecraft attitude control|attitude control]] systems were all test-fired to approximately 10,000 g's.<ref>{{Cite book|last=Bull, G. V. (Gerald V.)|title=Paris Kanonen--the Paris guns (Wilhelmgeschütze) and Project HARP : the application of major calibre guns to atmospheric and space research|date=1988|publisher=E.S. Mittler|others=Murphy, C. H. (Charles H.)|isbn=3-8132-0304-2|location=Herford [Germany]|oclc=24066021}}</ref>