Hermes Space Plane A presentation on the European Hermes Space plane from the 1980s By Andy Hill (Mar 2005)

1 Introduction Hermes was Europe’s first attempt at producing its own space plane design in the 1980s to give it independent access to manned spaceflight. Originally a French only project the development costs increased until France sought funding from other European countries, which it obtained mostly from Germany. The French space agency, CNES, started investigating a small spaceplane to be launched on top of the Ariane rocket -- 'Hermés'. By 1984, Hermés had evolved into a small mini-space shuttle capable of carrying a crew of 4-6 plus a 4500kg payload in its cargo bay. Hermes space plane concept - ESA

2 Introduction The American Challenger Shuttle disaster had a direct impact on Hermes leading to many added safety precautions which increased the craft’s cost and weight significantly. The craft’s weight increase during development resulted in the need for a more powerful launch vehicle which eventually became Ariane 5. Hermes’ final design would be to take 3 astronauts to orbits of up to 800km altitude for missions of 30 to 90 days in space. Hermes was to have been launched by 1998 but costs had risen to DM 12 billion by 1992 and the project was cancelled. Ariane 5 Launch - ESA

3 A time of expectations Hermes was conceived during a time of European growth in space amidst the success of the Ariane series of launchers. The next logical step for Europe would have been to develop its own manned spacecraft to support European manned missions to orbit. It was envisaged that Hermes would act as a ferry for European astronauts visiting a future European space station as well as being able to carry a small orbiting laboratory in its own right. Being smaller than America’s Shuttle meant that it would not have had to cope with the same heat loads and its more conventional heat shield would have made it easier to maintain. Hermes re-entering atmosphere - ESA

4 A time of expectations Hermes formed part of a much larger European space initiative which included a solely European space station which would have placed Europe on an equal footing with the US and Russia. Spiraling costs eventually meant the cancellation of a purely European venture in favour of international cooperation with the ISS. France, who had intially pursued Hermes on its own, sought funding from Europe for 50% of the costs. To save costs, the 1985 Hermes cockpit proposal based on computer displays from the Airbus commercial airliner was adopted. Even with such cost cutting measures the estimated cost for Hermes in 1986 was $1.5Bn plus a further $1.9Bn for its Ariane 5 carrier rocket. Hermes docked to space station - ESA

5 Design Changes In 1986 ESA started its preliminary Phase B2 study and agreed a $35m contract extension to determine the craft’s use and mission roles. Both Hermes and its Ariane launcher were approved by ESA in November 1987 at a total cost in of $4.25Bn and $3.36Bm respectively. Design changes, mainly to accommodate safety measures, had increased the space plane’s weight to 21,000kg even though the payload had been reduced to only 3,000kg inside a pressurised cargo compartment and the crew halved to 3. This extra weight required the Ariane launcher to have solid rocket boosters containing 230t (40t increase) of propellant and the central core to have 155t (15t increase) of liquid propellant. Hermes model on display at the 1985 Paris Airshow - ESA

6 Design Changes To solve some of the weight problems ESA decided to move some systems into an expendable aft-mounted docking module that would be jettisoned before returning to Earth. The new design was smaller and lighter, but the marginal cost per launch would be higher due to the expendable components. By 1990 the estimated cost of the Hermes project was $4.5Bn employing 1,500 people, ESA decided to delay the formal go-ahead of the next phase. ESA reorganised the project’s management to keep it on schedule, but it was becoming obvious that costs could not be contained and by 1991 estimates had risen to over $6Bn at which point ESA considered delaying the project by 2 or 3 years. 3D Hermes design - ESA

7 The End of Hermes A meeting in Germany in November 1991 posponed making difficult decisions for a year but the writing was on the wall as costs grew still further. In 1992 it was decided to reduce Hermés to a $ billion 'Hermes X-2000' unmanned technology demonstration. The November 1992 meeting in Spain, finally pulled the plug on 'Hermes X-2000' too, reducing the program's budget from $1.8 billion to $405 million. To be spent on paper studies only of a joint ESA/Russian Hermes, a US/European Crew Rescue Vehicle and for pure ESA in-house manned spaceflight options. A total of $2Bn had been spent when Hermes was eventually cancelled. Cut away of Hermes design - ESA

8 Summary Hermes suffered from problems almost from the beginning and like most space projects was subject to spiraling costs. However the impact of the shuttle disaster which caused a major redesign was probably the fatal blow which caused its cancellation. With a stretched ESA budget struggling to meet the space plane’s inflated cost as well as other projects such as Ariane, Hermes was doomed once major designs reduced its crew and a lack of a European space station made its role uncertain. It is probably true to say that the failure of Hermes has caused ESA to be wary of having its own manned space vehicle for a decade and it is only now that it is considering the possibility again of a new manned spacecraft. Hermes docked at space station - ESA

9 Acknowledgements This Presentation would not have been possible without the help of the following organisations or sources: European Space Agency (ESA) Encyclopedia Astronautica Encyclopedia Astronautica