It appears a feasible proposition, economically. That is the conclusion of a study that considered a European launch service based on a Skylon re-usable spaceplane.
The report, commissioned by the European Space Agency (Esa), was led by Reaction Engines Limited (REL) of Oxfordshire with help from a range of other contractors such as London Economics, QinetiQ and Thales Alenia Space (TAS).
It looked closely at how an operator of the UK-conceived vehicle might meet the demands of its market.
Those requirements would be primarily to loft big telecoms satellites high above the equator of the Earth, but also to put smaller, Earth-observing spacecraft in Sun-synchronous orbits (a type of orbit around the poles). These are the sorts of jobs the Ariane 5 rocket does today, and which Ariane 6, currently under discussion among European governments, may do from the early 2020s onwards.
Skylon is not in that discussion space at the moment - but it may get there at some point in the future if further technical studies prove positive and the financing can be found to push the concept forward.
The Skylon-based European Launch Service Operator (S-ELSO) study examined some of the hardware the vehicle would need to place satellites in orbit, and aspects of the economic model that would allow the operator to turn a profit. It even looked at how the vehicle could work out of Kourou in French Guiana - Europe's spaceport.
In all the areas the study considered, it found positive outcomes. The report was intended to provide Esa with the information it needs to help evaluate what would be a completely different way for Europe to go about its launcher business.
Skylon D1 To get telecoms satellites in position, Skylon would deploy a re-usable upper-stage propulsion unit
For starters, Skylon is nothing like the conventional rockets that Europe uses today. Skylon would operate like an aeroplane, taking off from, and returning to, a standard runway.
Ariane Traditional rockets dump exhausted boosters and propellant tanks as they ascend
Its technological trick would be its novel propulsion system - power units that work like jet engines at low altitudes and slow speeds, but then transition to full rocket mode at high altitudes and velocities in excess of five times the speed of sound.
This approach, if it can be made to work, would reduce that fraction of the vehicle's mass that must be carried as propellant, enabling the vehicle to take a practical payload to orbit in a single leap.
Although expensive to develop - think of a new Airbus design - it ought to be a good long-term investment because - again, like an Airbus - a Skylon is designed to be used over and over again. Today's rockets can be used just the once.
Indeed, the aviation model is a good one, because the idea as currently envisaged is that there would be a vehicle manufacturer (like an Airbus or a Boeing) that would sell Skylons to many operators (space equivalents of BA, Air France, Lufthansa, etc).
Via the BBC. More at link. http://www.bbc.co.uk/news/science-environment-27591432
Ram rocket engines are not exactly new technology. Rolls Royce developed a highly successful engine in the mid 70's. It tested out perfectly, but the UK space program got put on indefinite hold.