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A new small geostationary platform, capable of supporting variable communications payloads with up to 3kW of power and 250kg in mass, is currently under development at SSTL. The platform shall utilise a conventional MMH/NTO bipropellant propulsion subsystem to provide the necessary delta-V required for transfer orbit manoeuvres and station keeping for up to 15 years. The system comprises a 400N main engine, and 16 smaller reaction control thrusters all fed from 2 x 700L propellant tanks individually pressurised with helium by means of an electronic (bang-bang) pressure regulation system. This paper presents an overview of the system architecture and details the preliminary analysis performed, along with the results obtained from the first phase of design verification tests carried out on an engineering model of the propellant feed system. The results provided confirmation of the steady-state flow characteristics and retired the risks associated with hydraulic shock transients (water-hammer) occurring in the propellant lines during priming, which could have an adverse effect on subsystem performance.