FOR the fledgling space tourism industry Falcon 1’s successful launch on 28 September was hugely significant. When the rocket, built by SpaceX in Hawthorne, California, reached orbit 500 kilometres above the Earth it was the first privately developed rocket to do so.
Then two days later Virgin Galactic struck a deal with the US National Oceanic and Atmospheric Administration that will allow US scientists to monitor climate change using its spacecraft.
No doubt about it, the civilian space flight industry is on a high, and nowhere was this more apparent than at the International Astronautical Congress in Glasgow, UK, last month, where executives wielding slick promotional videos and models of “nearly ready” spacecraft were promising sub-orbital flights to people with deep pockets.
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Yet despite growing confidence, a serious note of caution is being sounded: can civilian spacecraft ever be as safe as holiday airliners? At the moment there are no global, legally enforceable standards that guarantee the safety of civilian spacecraft, says Gérardine Goh, a lawyer at DLR, the German Aerospace Centre in Bonn and an adviser to Germany’s delegation to the UN’s Office of Outer Space Affairs. “Ships have to be seaworthy, aircraft have to be airworthy. But there is no legislation as yet that will ensure a spacecraft is spaceworthy,” she told IAC conference delegates.
So along with like-minded engineers, lawyers and policy makers at the International Association for the Advancement of Space Safety, a Netherlands-based not-for-profit group, Goh is advocating the development of minimum safety standards for civilian spacecraft.
They hope their ideas will one day feed into rules adopted by a future global regulator, possibly a UN-backed one. This might ensure safety in space in a way similar to how the UN’s International Civil Aviation Organisation currently regulates safety in aircraft. “There is currently no international minimum safety standard for mass commercial space flight,” Goh says. “We need a basic UN treaty that gives us that.”
For example, one way companies are planning to get tourists into space is with an aircraft “mother ship” that carries a rocket to an altitude of around 16 kilometres before launching it, says Goh. “But with an aircraft launch, the ICAO air safety standards only apply to the mother ship and to the rocket capsule until it has separated. After that, we have no agreed safety standards for the capsule itself. That’s a big problem.”
So from 16 kilometres to the Kármán line, the point 100 kilometres up where space is deemed to start, the rocket will be travelling in a legal vacuum, where lawyers cannot agree whether it is a plane or a rocket. Some say only air law applies at or below 100 kilometres. Others, like Goh, argue that if you are in a fully functioning rocket, some agreed minimum safety measures should apply to the spaceship’s design. Such confusion could expose fledgling space firms to a debilitating blizzard of writs in the event of an accident.
Other aspects of the UN’s 1967 treaty on the exploration and use of outer space may also need revisiting if civilian space flight proves successful. For instance, countries are obliged to rescue and repatriate astronauts who crash or land in their territory. Governments might decide that the costs of rescuing space tourists should be met by the space flight operators.
Civilian space flight companies hardly need a reminder of the risks they are working with, as the field has already experienced its first major tragedy – on the ground. In 2007, three engineers were killed and three others badly injured when nitrous oxide rocket fuel exploded for reasons that remain unclear during fuel flow tests at a Scaled Composites facility in Mojave, California. The firm is building WhiteKnightTwo, a carrier aircraft, and SpaceShipTwo, a six-seater rocket, for Virgin Galactic. Scaled was fined by California’s health and safety regulator and is modifying its technology to reduce risks ().
But the dangers of space flight go far beyond fuel issues. Other major safety factors include depressurisation risks, passengers’ proximity to the engine, the dynamics of flight trajectories (see “You spin me right round”) and even cosmic ray shielding, says Laurent Gathier of Dassault Aviation, which is developing the VSH, a rocket-powered sub-orbital tourist spaceplane. “Safety is driving the design of the VSH,” Gathier says.
Civilian space companies tend to believe that safety is already built into their designs. For example, the VSH will have an ejector seat for every tourist and crew member – allowing them to bail out of a crippled craft at around 40,000 feet (12 kilometres).
The notion of applying minimum regulations is fiercely resisted in the US, where the Federal Aviation Administration’s Office of Commercial Space Transportation (AST) has no plans to regulate civilian space flight safety until 2012. The Commercial Space Launch Amendments Act of 2004 states that civilian space flight regulation must not “stifle” the developing technologies with onerous rules, says AST chief George Nield.
“In the long term we need certification, yes,” says Melchor Antuñano of the AST. “But in aviation it took many years to develop safety standards. With civilian space flight we are now at the level of the Wright brothers, and if you had asked the Wrights to comply with certification requirements they would never have launched the Flyer. So we cannot be too strict too soon.”
“Civilian space flight is now at the level of the Wright brothers. We mustn’t stifle it”
The trouble is that a hands-off approach may scupper civilian space flight before it really gets going. “A lack of safety standards, and the resulting high liability for operators, will leave commercial space flight in the hazardous sports category for insurance,” says Goh. That means insurance costs will keep fares stratospheric.
Critics of attempts to develop safety regulations also argue that the “at-your-own-risk” model that applies to risky sports such as scuba-diving should be applied to civilian space flight.
That would be unworkable, says Goh. “If six or seven very rich people die in one huge crash, it might actually kill civilian space flight, as launching states will panic about liability and start refusing launch licences,” she says. “Some minimum safety standards may prevent that.”
You spin me right round…
People paying $200,000 for a sub-orbital flight with Virgin Galactic are in for a stirring time. To ensure they can handle the 3 g on the way up, and up to 6 g on the way down, Virgin is testing its would-be space tourists’ resilience in a centrifuge. Two of the first 100 customers have failed the tests. “They weren’t medically up to it,” says Virgin president Will Whitehorn.Forces can get much higher, though. If an engine fails on ascent, aborting a mission can generate far worse g loads than expected, warns Alexander Filatyev of the Moscow Aviation Institute. It is harder to abort at low g when a rocket is flying at its most fuel-efficient, mathematically optimal trajectory, he says. In 1975, for instance, two cosmonauts suffered engine failure, sending their capsule into a sudden sub-orbital flight which subjected them to excruciating 20 g forces.Tourist craft should fly trajectories that burn a little extra fuel but allow for easier aborts, Filatyev suggests.
Prepare to enter the escape pod
An emergency space module that can protect tourists and astronauts from the colossal heat of re-entering Earth’s atmosphere at 29,000 kilometres an hour is being developed.The Spacecrew Emergency Module, the brainchild of Anglo-Italian firm Aero Sekur based in Farnborough, UK, will allow space tourists and astronauts to escape a doomed spacecraft. The idea for the “suit” evolved in the wake of the Columbia disaster in 2003, when the shuttle disintegrated during re-entry following damage to its heat-proofing.At the flick of a switch, the inflatable back-pack will envelop the astronaut in a heatproof silicon cone, with a diameter of 3 metres. Once into the atmosphere a second device will inflate at 8 to 10 kilometres from the ground, acting as a parachute to slow the astronaut or passenger and allow them to land safely.Aero Sekur’s engineer Giacomo Giovangrossi told last week’s International Association for the Advancement of Space Safety meeting in Rome, Italy, that the personal inflatable devices have so far withstood the 1400 °C heat and physical pressures of simulated re-entry conditions in a plasma wind tunnel. “This is the first time anyone has shown this,” he says.Importantly, the adhesives and stitching holding the device together also withstood the conditions, says Giovangrossi. The next step will be to subject a smaller 1-metre-diameter version of the device to a real re-entry. The company has approached the European Space Agency and Virgin Galactic for financial help. Giovangrossi hopes the devices will be on sale within 10 years.Michael Day
