Space Transportation covers both delivery of objects (people, spacecraft, consumables) into Earth orbit, and the transfer of objects already in orbit between locations. This is primarily between different Earth orbits, but increasingly the world’s space faring nations are sending probes to our Moon, Mars and beyond. Regardless of the destination, propulsion technology including are essential for timely efficient and affordable space transportation to take place.  

High thrust propulsion releases stored energy of oxidisers and fuels to create high temperature gases in a combustion chamber made of specialist materials which can then be directed by a nozzle to supersonic velocities. 

Performance can be increased by use of (turbo)pumps to raise combustion pressure. Additive layer manufacturing techniques are being trialled for key components. Storage of propellants, which may be cryogenic, in lightweight robust and affordable pressure vessels is a major technical driver for high thrust chemical propulsion. UK design, manufacturing and test skills in these areas are national enablers and can be highly exportable. 

Electric propulsion can be further divided into electrothermal, using electrical heating of propellants, electromagnetic, using magnetic/electric fields to accelerate plasma, or electrostatic, accelerating an ionised propellant using purely electric fields.  

Almost all spacecraft require some form of propulsion, and electric propulsion due to its high efficiency is increasingly dominating new space projects. However, many new applications such as planetary landing, and in-orbit debris removal require both low and high thrust, and high efficiency (Isp). Rapid in space transportation, which is constrained by the low thrust of electric propulsion is also sought by commercial spacecraft and human carrying vehicles which will need regular, efficient access to the Lunar Gateway and beyond.  

APPLICATIONS

UK companies build components, subsystems & propulsion systems; high & low thrust engines; chemical & electric propulsion. The UK also offers numerous sea level and high altitude plus high vacuum test facilities, suited to chemical propulsion up to around 30kN (SL) and 2kN (vacuum), and electric propulsion up to 500mN thrust levels. 

Between 2016 and 2021 the UK government invested over £4M in facilities to test chemical thrusters up to 2kN under vacuum at the Westcott site, which also offers world class capabilities in propellant manufacture, characterisation & environmental testing.

Westcott is also the production site of the Leros series of small thrusters & apogee engines, delivering unparalleled performance as far as Jupiter and in the near future for Mars Sample Return. Commercial companies such as Orbex & Skyrora have also invested significantly in high thrust engine test facilities in Scotland to support their launch vehicles. 

ELECTRIC PROPULSION, EP TEST & DIAGNOSTIC

The UK has a long heritage in electric propulsion, having developed early gridded engines, with several of the most recent T6 thrusters en-route to Mercury on the ESA Bepi-Colombo science mission.

Research into next generation electric propulsion continues at universities with Southampton, Imperial, Surrey and UCL having vacuum test chambers, supporting numerous commercial companies developing EP for many space

DID YOU KNOW?

Satcom connectivity has been available at a price premium. Advancements in technology are allowing to significantly reduce the cost per unit of capacity in the order of 10X. Operators are looking to more capable and flexible satellite architectures to optimize the cost of connectivity.  Satcoms are becoming more competitive with further margin for improvement.

Depending on the application, user terminals cost has its importance for service adoption.  Terminal technology development is ongoing with progress in cost and performance.