The past year has been a boom time for the commercial spaceflight industry. NASA chose which private companies will shuttle supplies and people to the International Space Station (Boeing and SpaceX). And within three years, the agency hopes to no longer be dependent on Russia to get American astronauts and supplies into orbit.
Looking further afield, the space agency also launched the first Orion deep-space capsule, built by Lockheed Martin, on a successful test flight. The December flight had space enthusiasts excited about potentially taking a step closer to sending humans to Mars.
But alongside the successes have come failures, even tragedies. When the fatal crash of Virgin Galactic's SpaceShipTwo occurred in the same October week as the loss of an Antares rocket made by Orbital Sciences, supporters and detractors vociferously debated private spaceflight. "Space Tourism Isn't Worth Dying For," declared a headline on Wired.com. "Discrediting Space Tourism Insults the People Who Risk Their Lives for It," shot back another editorial on the same website. [ Top 10 Intrepid Explorers ]
Behind all of the rhetoric, however, members of the aerospace community ruminate over safety quite a lot — and recognize the likelihood of accidents without accepting the inevitability of accident-related deaths.
"Accidents can happen. We are talking about very complex machines that can have unpredictable behavior," said Andrea Gini, the editor-in-chief of Space Safety Magazine and chair of information and communication at the International Association for Advancement in Space Safety (IAASS). Nevertheless, Gini said, "death is not inevitable."
A history of accidents
On Oct. 28, Orbital Sciences' unmanned Cygnus spacecraft, powered by an Antares rocket, exploded into an enormous fireball only moments after launch. An investigation is ongoing, but Orbital Sciences Corporation has said that a turbopump failure likely caused the disaster. Three days later, Virgin Galactic's SpaceShipTwo crashed during a test flight, killing the pilot and injuring the co-pilot. Preliminary information suggests the pilot may have misused a device intended to move the spacecraft's wings into landing position, unlocking the device too early in the flight and causing the wings to detach.
Transportation disasters precede commercial spaceflight, and indeed human flight itself. Experimental vehicles have always come with a certain level of risk. In 1815, one of the earliest locomotives, Brunton's Mechanical Traveller, exploded during a demonstration, sending scraps of metal and scalding water from the boiler into the crowd in Philadelphia, England. Sources vary on the number of casualties, but either 13 or 16 people died, according to historical reports.
Boiler explosions remained a frequent cause of railway deaths for the next century. According to the American Society of Mechanical Engineers (ASME), thousands of boilers exploded in the late 19th century, including on the steamship Sultana in 1865, when more than 1,500 people died. [ Top 10 Biggest Explosions ]
At the time, safety inspections and standards were entirely lacking, even though steam power had become integrated into American and European life. It wasn't until a 1905 factory boiler explosion in Brockton, Massachusetts, that public outcry forced a policy change. The ASME created a series of standards for boilers the following year, and published the first-ever boiler code in 1914.
Early air travel had its share of disasters, as well, but the participants in those dramas were usually well aware of the risk, said Roger Launius, the associate director of collections and curatorial affairs at the Smithsonian National Air and Space Museum.
"You have to remember, this is adventure stuff, so only adventurers do it — daredevils, people looking for an adrenaline rush," Launius told Live Science.
The first fatal air crash dates all the way back to 1785, when French hot air balloonist Jean-François Pilâtre de Rozier and his copilot, Pierre Romain, crashed their hybrid hot-air and hydrogen-gas balloon while attempting to cross the English channel. In 1908, only five years after the first successful airplane flight by the Wright brothers, Orville Wright was involved in the first fatal airplane crash. An Army Lieutenant named Thomas E. Selfridge was Wright's passenger on the fatal flight, which was part of a demonstration meant to prove that the brothers' Flyer aircraft could carry more than just the pilot. An unnoticed crack in the propeller sent the Flyer plummeting, killing Selfridge and injuring Wright badly.
Those accidents, and later ones like them, prompted design changes and improvements to early aircraft — though Launius points out that daredevil pilots at air shows still have fatal accidents with some frequency.
Test pilots, though, are different, Launius said.
"You don't survive to be an older test pilot if you're just a daredevil," he said. The people who put themselves on the line to develop spacecraft and military jets aren't in it for the adrenaline rush, he said. "They are willing to accept risk, and they recognize that they could die in the process, but that's not their intention at all."
For Leroy Chiao, a former NASA astronaut who flew on three space shuttle flights to the International Space Station during his career, risk was always at the forefront when preparing for a launch.
"At the end of the day, I made a conscious decision that I wanted to do this, so I was willing to accept the risks, knowing that everything had been done by me and by the system to try to minimize those risks," Chiao said.
One of the biggest challenges in a safety culture is to avoid "cultural creep," in which troublesome issues are brushed off, Chiao told Live Science. For example, NASA engineers knew for years that the space shuttles sometimes shed foam insulation tiles from their exteriors during launch. "Everybody got used to it," Chiao said.
Then, in 2003, one of those foam tiles hit the wing of the Columbia space shuttle during launch. Just over two weeks later, when the shuttle re-entered Earth's atmosphere, the damage to the wing led to the entire shuttle breaking up. All seven crewmembers died in the accident.
Cultural problems were at play as well during the space shuttle Challenger disaster in 1986, when freezing temperatures compromised the seals on the shuttle's boosters. Some in NASA had voiced concerns over the seals, but those warnings did not make it to the ultimate decision-makers.
Organizations, whether NASA or Virgin Galactic, typically learn from their mistakes. But that doesn't mean that mistakes are necessary, Space Safety's Gini said.
"A lot of people tend to believe that you cannot anticipate an accident until it happens," Gini said. "So the idea is that commercial air flight, for example, is safe because in the past we had a lot of accidents. But it is not really like that."
In fact, safety organizations in the commercial air flight industry have been promoting design and technical standards for decades, Gini said.
"This is what we would like to promote also, in particular for the commercial spaceflight industry," he said.
Currently, that industry operates under relaxed regulation from the federal government (though any contract with NASA is still subject to the agency's safety standards). Since 2004, the Commercial Space Launch Amendments Act has prohibited the Federal Aviation Administration (FAA) from issuing design regulations for the protection of passengers. The goal was to let private spaceflight companies begin testing without onerous red tape; in 2012, the law was renewed until 2015. However, the death of a test pilot may override that moratorium, the MIT Technology Review has written.
While accidents are likely inevitable as engineers push the envelope, loss of life doesn't have to be, Gini said. Redundant safety systems can prevent deaths in the event of accidents. In the case of Orbital Sciences' Antares rocket explosion, the system actually worked; an operator ordered the rocket to self-destruct once it began to malfunction, containing the explosion to the launch site and keeping it away from populated areas.
Ultimately, Gini said, the dawn of commercial spaceflight does not have to be as deadly as the dawn of air flight.
"We have a lot of knowledge that simply didn't exist back then," he said. "We have been to the moon and back. We have created rockets. We have airplanes. We have cruise ships that are as big as cities. We have power plants and chemical plants that operate safely in very dangerous conditions."