Personal Interest - Unbuilt British Space Projects

Introduction


These are a few examples of British space projects that were studied and examined. Some of them had UK government support and funding while others were either company led and developed or done under private research. Sources and images include secretprojects forum, flightglobal archive, aviation week archive and the BIS site.

BAe HOTOL


This single-stage-to-orbit winged horizontal takeoff or landing (HOTOL) launch vehicle concept was powered by the unique Rolls-Royce RB545 air / liquid hydrogen / liquid oxygen rocket engine. HOTOL development was conducted from 1982 to 1986 before the British government withdrew funding. It was superseded by the Interim HOTOL design which sought to reduce development cost through use of existing LOx/LH2 engines.


HOTOL development was begun in 1982 by a Rolls-Royce / British Aerospace team led by John Scott and Dr Bob Parkinson. The project was reasonably well advanced (engine detailed design and mockup) by the time the British government withdrew further funding in the mid-1980's. HOTOL would have taken off horizontally from a runway, from a purpose made, rocket propelled trolley. It would transition to pure rocket propulsion at Mach 5.0 - Mach 6.0 and ascend to orbit. A moderate re-entry profile would decrease the thermal loading constraints. HOTOL would return via a glide landing, to a landing on gear on a conventional runway.
The original HOTOL airframe design was derived from conventional vertical takeoff rockets with the engines mounted at the rear of a blunt based fuselage. Since such a vehicle's empty center of gravity was dominated by the engine location, the wings and the tank for the dense liquid oxygen also had to be at the rear. The payload bay and hydrogen tankage were placed in a projecting forebody. 
The resulting configuration suffered from a severe center of pressure / center of gravity mismatch during the air breathing ascent. The center of pressure shifted 10 m forward, due to the wide Mach range, the large fuselage cross section to wing area ratio, and the long overhang of the forward fuselage. Various alterations were made to the design to handle these problems, all of which eroded the payload. 
Conventional landing gear were replaced by a specially designed takeoff trolley in order to improve the marginal payload fraction. The final design had serious operational disadvantages and a small payload. The only way the designers could continue to claim to put a reasonable payload into orbit was by specifying untried and speculative structural materials.

BAe Multi-Role Capsule

This was a British manned spacecraft study from 1987. The British govnerment or more specifully the civil service depending on the viewpoint of Britains interest and comminment to the space race  was the only European Space Agency (ESA) member opposed to ESA's ambitious man-in-space plan, and the British conservative government refused to approve the November 1987 plan.

Manned Reusable Capsule. Status: Study 1987. Payload: 500 kg (1,100 lb). Thrust: 1.61 kN (361 lbf). Gross mass: 7,000 kg (15,400 lb). Unfuelled mass: 6,300 kg (13,800 lb). Specific impulse: 312 s. Height: 4.28 m (14.04 ft). 

However, the British aerospace industry did propose some interesting alternatives, such as the $2-billion 'Multi-Role Recovery Capsule'.


British Aerospace Ltd. (BAe) regarded the French Hermes mini-Shuttle as too expensive and complicated. Instead, they felt a simple crew capsule would make more sense as an 8-man 'lifeboat' for Space Station Freedom (NASA issued a competitive request for proposals in late 1987). MRC was to be launched on the existing Ariane-40 rocket (a varient of the Ariane-4) and the capsule could be flown manned or unmanned, for sensitive microgravity experiments in orbit.

Zircon (satellite)

During the Cold War, Britain's GCHQ was heavily reliant on America's National Security Agency (NSA) for communications interception from space. Concern heightened at the time of the Falklands War. GCHQ requested access to American Signals Intelligence satellites to assist in monitoring Argentine Communications, but reportedly struggled with the National Security Agency to gain appropriate tasking time, despite the special relationship between the two countries. The United States satellites were engaged in monitoring SIGINT traffic elsewhere in South America related to El Salvador. GCHQ therefore decided to produce a UK-designed-and-built signals intelligence satellite, to be called Zircon, a code-name derived from zirconium silicate, a diamond substitute. Its function was to intercept radio and other signals from the USSR, Europe and other areas. The Satellite was to be built at Marconi Space and Defence the Airport Portsmouth UK, at which a new high security building had been built and would have secured jobs in the surroundng area. It was to be launched on a NASA Space Shuttle under the guise of Skynet IV. Launch on the Shuttle would have entitled a British National to fly as a Mission Specialist and a group of military pilots were presented to the press as candidates for 'Britain's first man in space'.

Army Lieutenants-Colonel Anthony Boyle (born in Kidderminster) and Richard Farrimond (born in Birkenhead, Cheshire), MoD employee Christopher Holmes (born in London), Royal Navy Commander Peter Longhurst (born in Staines, Middlesex) and RAF Squadron Leader Nigel Wood (born in York) were selected in February 1984 as payload specialists for the Skynet 4 Programme, intended for launch using the Space Shuttle. Boyle resigned from the programme in July 1984 due to Army commitments. Prior to the cancellation of the missions after the Challenger disaster, Wood was due to fly aboard Shuttle mission STS-61-H in 1986 (with Farrimond serving as his back-up) and Longhurst was due to fly aboard Shuttle mission STS-71-C in 1987 (with Holmes serving as back-up). All resigned in 1986, having not flown.

Zircon was cancelled by Chancellor Nigel Lawson on grounds of its cost in 1987. Following the cancellation the UK is believed to have paid for a NSA MAGNUM SIGINT satellites. This arrangement allows the UK to operate its own satellite. 

British Interplanetary Society (BIS) - Daedalus and World ship 

The British Interplanetary Society (BIS) was founded in 1933 by a group of space flight enthusiasts who dreamed of using rocket propulsion to fly to the Moon and the planets. The word “Interplanetary” in the British Interplanetary Society’s title was not intended to limit attention only to those nearby worlds that circle our Sun, but to cover space exploration activities in general – even in the most distant visions to conceive of travel across interstellar space.

As part of this durings the 70s and 80s they carried out a studies to examine what would be reqruied to build a space probe to research other solar systems and what kind of vessels would be needed for interplaetary flight. These led to the Daedalus and World ship projects.

Project Daedalus was a study conducted between 1973 and 1978 to design a plausible unmanned interstellar spacecraft. Intended mainly as a scientific probe, the design criteria specified that the spacecraft had to use existing or near-future technology and had to be able to reach its destination within a human lifetime. Alan Bond led a team of scientists and engineers who proposed using a fusion rocket to reach Barnard's Star 5.9 light years away. The trip was estimated to take 50 years, but the design was required to be flexible enough that it could be sent to any other target star.

There were three stated goals for Project Daedalus:

• (1) The spacecraft must use current or near-future technology

• (2) The spacecraft must reach its destination within a working human lifetime

• (3)The spacecraft must be designed to allow for a variety of target stars. The final design solution was published in a special supplement of the Journal of the British Interplanetary Society in 1978.

The two-stage engine configuration was powered by inertial confinement fusion using deuterium and helium-3 pellets. Electron beam diodes positioned around the base of the engine exhaust would impinge on the pellets and ignite them to produce large energy gain, at a rate of 250 detonations per second. This would continue for a boost phase lasting over 3.8 years followed by a cruise phase lasting 46 years and travelling at over 12% of the speed of light until the 450 tons science probe would finally reach its destination of the Barnard’s Star system 5.9 light years away, which it would transit in a matter of days due to its flyby nature.

In the final study reports all of the main vehicle systems were considered including the structure, communications, navigation and the deployment of mitigation sub-systems to deal with the bombardment of interstellar dust. 

In 1929 John Desmond Bernal designed a concept for a visionary form of interstellar space structure. Known thereafter as a “Bernal sphere”, the vessel was essentially constructed from asteroid and Moon material, 16 km in diameter with a population of around 20,000 people. A atmosphere would be provided within the structure so that it became a self-contained habitat. The outer shell would be hard, transparent and thin, preventing the escape of gas and allow for the preservation of a rigid structure. The Bernal sphere was mainly designed as a space habitat, but this visionary ideas laid the ground work for the more rigorous studies that were to follows. The American engineer Gerrard K.O’Neill took this work to a new level in the 1970s when he also designed large human habitat structures that could accommodate tens of thousands of people. O’Neill planned that such structures would be loaced at the L5 point in space, a region where the gravity from the Moon, Earth and Sun is neutral.

The work on large space habitats, laid the groundwork for an even more visionary idea, that of giant World Ships – vesself that would travel the distances between the stars. The motivations for developing world Ships related to the long-term stability of the Sun, the security of the human species against natural of man-made disasters and the undertaking of interstellar exploration for the sake of scientific discovery and human expansion. These World Ships would explore the galaxy on travel times lasting a thousand years or more. The material needed to construct them would come from extraterrestrial resources. 

In particular, Bond and Martin designed actual World Ship vessesls as an assessment of the engineering feasibility, which are arguably the most detailed consideration of the problem in history. They designed a “Dry World Ship” concept which had a radium of 7.24 km, wall thickness 2.88 m, rotation period 169 seconds. It would require billions of tons of wall mas, regolith mass, atmosphere mass, with the total habitat mass of 168 billions tons. The propellant mass, would be 779 billion tons. The engine would consist of a heterogenous structure called a pulse unit, which would consist of an oblate sphere of frozen hydrogen with a solid deuterium core. Each unit would be ejected from the World Ship, rotating about the flattened polar axis and with its axis along the direction of motion. The pulse units would have small hole leading from the pole facing the world ship down to its core and a metallic slug (the initiator) ejected from the World Ship at about 1,000 km/s would pass down this hold and hit the core. The pulse unit would be several tens of km from the World Ship at the time of detonation. Upon striking the deuterium core a shock system would be established, across which the deuterium would be brought to self-igniting conditions. 

As if that wasn’t enough, they also designed a “Wet World Ship” version. This greatly complicated the engineering problem due to water having a density over 800 times greater than air. The final concept had a radius of 5 km, a wall thickness of 9.15m and a rotation period of 314 seconds. The total habitat mass was 345 billon tons carrying 8,633 billions tons of propellant mass. The ocean mass would total 1,676 billion tons, plenty of water for on board swimming. 

Worldship arrival at new planet

Worldship Ocean