Dr Alan Bond, Reaction Engines Limited

The Key to Economic Hypersonic Flight and Access to Space:

Hydrogen Fuelled Pre-Cooled Jet Engines

by Dr Alan Bond, Managing Director, Reaction Engines Limited

Tuesday 03 June 2008

SPECIAL EVENT

Public open lecture - All visitors welcome - No admission fee - No tickets required - Doors open 5:30pm

Reaction Engines Limited

Skylon is an unpiloted, reusable spaceplane intended to provide inexpensive and reliable access to space. Currently in proof-of-concept phase, the vehicle will take approximately 10 years to develop and will be capable of transporting 12 tonnes of cargo into space.

Skylon will be an order of magnitude cheaper to customers than current space transportation systems, and has been designed as a practical utilitarian machine for use by competitive commercial operators. This is seen as the most effective way to ensure that space transportation assumes its proper place in the economy and its continued improvement under "customer control". This dictated a configuration as close to a conventional aircraft as technology will permit. In particular a rolling take-off is seen as essential.

Initially operations will probably begin from existing sites built either for space or aircraft which have been modified to suit Skylon vehicles. However in the longer term (within ten years of introduction) operations would probably move to international equatorial sites since these offer maximum launch opportunities of at least two windows per day and access to any orbit. The eventual equatorial launch sites, or spaceports, are envisaged to be international from the point of view of the operators using them and would be established by share investment; profits would be made by leasing the facilities to the spaceline operators. It is expected that three spaceports would be operating at equatorial locations by 2020-2025.

LAPCAT: Long-Term Advanced Propulsion Concepts and Technologies. Reaction Engines is engaged on an EU 50% funded project to examine the propulsion concepts and technologies required:

"... to reduce long-distance flights, eg from Brussels to Sydney, to less than 2 to 4 hours. Achieving this goal intrinsically requires a new flight regime for commercial transport with Mach numbers ranging from 4 to 8."

To fulfil this mission requires a hypersonic aircraft with near antipodal range (20,000 km). To achieve the range requirement liquid hydrogen fuel is mandatory since the specific calorific energy of hydrocarbon fuels is too low. Reaction Engines have conceived the Scimitar pre-cooled engine concept which is capable of sustained Mach 5 flight. In addition the engine has a second operating mode that features a high bypass airflow permitting efficient subsonic flight and moderate takeoff noise.

Analysis of the development, production and operating costs suggests that the average ticket price would be comparable to an existing Business class ticket. Therefore the A2 vehicle could in principle capture all of the current business and first class traffic due to the greatly reduced journey time of 4.6 hours compared to the current 22 hours. Also the analysis assumes no hydrogen subsidy, however in reality it is likely that the first generation of hydrogen fuelled aircraft would be subsidised to promote the switch to a more environmentally friendly fuel.

Unlike Concorde, the A2 vehicle has exceptional range (approx 20,000 km both subsonic and supersonic) and is therefore able to service a large number of routes whilst simultaneously avoiding supersonic overflight of populated areas. Its good subsonic performance enables it to service conventional subsonic overland routes thereby increasing its sales potential to airlines.

Alan Bond began work on spaceplane engines in 1982 with a view to overcoming the inadequate characteristics of existing rocket-based expendable launch systems. This work culminated in the patenting of a new type of engine employing a novel thermodynamic cycle, whose characteristics were specifically tailored to the requirements of a single stage to orbit spaceplane.

Pre-cooled jet engines using liquid hydrogen fuel as a heat sink to cool the incoming air at high Mach numbers have been in the literature since the early 1960s. However it is only with the innovative engine cycle of the RB545 of the HOTOL project in the 1980s that the performance began to outweigh the weight penalty of these concepts. Continued research into thermodynamic cycles, hardware design, materials and component manufacture have now resulted in propulsion concepts which can creditably yield vehicle designs capable of cheap access to space and economic hypersonic antipodal flight in about 4 hours. This talk will present the current state of art for this propulsion concept and its applications, the status of the ongoing development programmes, and examine what are the essential next steps, both technological and political, in bringing this tremendous promise to reality.

PROGRAMME
17:30	Doors open: Opportunity for networking
	Refreshments: Tea and biscuits
18:00	Welcome: Pat Norris, Chairman, RAeS Space Group
	Introduction: Prof Jim McGuirk, Chairman, RAeS Propulsion Group
	Presentation by Dr Alan Bond, Managing Director, Reaction Engines Limited
	Questions to the speaker
	Further opportunity for networking (cash bar)
20:00	Close

Public open lecture : all visitors welcome : no admission fee : no tickets required

commencing at 18:00, refreshments served from 17:30

This lecture has been organised jointly by the Royal Aeronautical Society (RAeS) Space Group and the RAeS Propulsion Group. The presentation will take place in the Lecture Theatre at 4 Hamilton Place, London W1J 7BQ. Nearest underground station Hyde Park Corner. See location maps doc.. also multimap.com.. streetmap.co.uk..

For further details: Ms Hinal Patel, Conference & Events Department, Royal Aeronautical Society, 4 Hamilton Place, London W1J 7BQ. tel 020 7670 4345 fax 020 7670 4349 email conference@aerosociety.com

To receive details of the RAeS Space Group and other future events please an email to space@aerosociety.com with "subscribe" in the subject.