Ground and flight tests of AlSat-1B butane propulsion system

D. Darfilal ^a,*, D. Gibbon ^b

a. Satellite Development Center CDS, Algerian Space Agency ASAL, BP 4065, Ibn Rochd USTO, Oran 31130, Algeria
         b. Surrey Satellite Technology Ltd, Guildford, Surrey GU2 7YE , United Kingdom

Abstract: On 26th September 2016 Algerian Space Agency launched AlSat-1B, the second in a series of medium resolution earth observation satellites mission. AlSat-1B electro-thermal propulsion system follows the classic design principle that has been used on previous SSTL-100 missions. With a total dry weight of 5.17 kg, the system is filled with 2.35 liters self-pressurized butane. The thruster assembly is designed to use 15 watts (at 28 V) redundant heater elements, it is designed to have an average mission thrust of 50 mN. With a warm up time of 10 minute, the temperature of the butane will be increased by over 250 °C. This is the equivalent of about 35% gain in specific impulse over ambient temperature butane. The spacecraft dry weigh at launch site was 107 kg, the propulsion system is designed to provide at least 19 m/s Delta-v to meet the spacecraft's mission requirement. To investigate the system readiness for flight, a series of performance tests have been completed at the Surrey Satellite Technology Ltd laboratories (United Kingdom), Satellite Development Centre (Algeria) and Satish Dhawan Space Centre rocket launch site (India), the results of these tests as well as initial flight test results are presented in this paper.

Keywords: Space; Propulsion; Butane; Resistojet; Heaters; Specific impulse

https://doi.org/10.1016/j.jppr.2022.02.005