WASHINGTON – If U.S. airlines had the same failure rate as the now-retired space shuttles, there’d be 272 fatal crashes a day.
As the investigation begins into the unmanned Orbital Sciences Corp. rocket that blew up seconds after liftoff this week, the history of space travel suggests such failures are neither rare nor unexpected.
“You have so much energy required to get out of the Earth’s gravity field, you’re always essentially sitting on a bomb,” John Hansman, a professor of aeronautics and astronautics at the Massachusetts Institute of Technology, said. “You’re basically trying to have the bomb go off in a controlled way.”
Not only are rockets packed with explosive fuel, they are also complex machines made up of thousands of moving parts that can fail spectacularly over even a modest hiccup. It takes years to understand how systems may fail and where vulnerabilities lie, making it even more difficult to reduce risks as private companies get into the business of providing “space taxis” shuttling travelers and supplies into orbit.
Companies such as Virgin Galactic will have to address such risks before selling tickets to space travelers, Paul Ceruzzi, chairman of the Smithsonian’s National Air and Space Museum’s space history division, said in an interview.
“They have to address the safety issue very carefully,” Ceruzzi said.
The $200 million Antares rocket and spacecraft exploded in an orange plume over the Wallops Flight Facility on Virginia’s eastern shore on Oct. 28.
After an unspecified failure occurred seconds into the launch, Orbital’s engineers intentionally destroyed the craft, Frank Culbertson, an executive vice president for the Dulles, Virginia-based company, said at a news conference the night of the accident.
The rocket’s first stage is powered by a mix of kerosene and liquid oxygen. Its engines are the AJ-26, a refurbished version of Russian-made NK-33 models. The company has had issues with the engines and is speeding plans to move to a newer type, Orbital Chief Executive Officer Dave Thompson said on a conference call with analysts.
Out of 284 launches in more than 30 years, the company has succeeded 95 percent of the time, he said. The record improved to 96 percent in its 106 launches in the last 10 years, he said.
The overall unmanned rocket success rate is about the same, Ceruzzi said.
By comparison, U.S. airlines reported one fatal crash in the past five years, a success rate of 99.999998 percent.
“Unless somebody invents warp drive or something else, the physics are just there,” he said. “To go from zero to 17,500 miles an hour in a very limited amount of time, iron clad rules of physics come into play and you can’t get around them.”
The space shuttle, designed to carry large payloads into space and then glide back to Earth so it could be reused, suffered two failures in its history from 1981 to 2011. Both were triggered by the violence of launch.
In 1986, one of shuttle Challenger’s two booster rockets developed a leak of hot gas that caused it to break apart and explode.
Engineers at NASA initially thought they had designed the shuttle to have a risk of failure of one in a thousand or better. Only after the accidents and a more thorough review of potential failures did the space agency’s engineers understand how risky it had actually been.
A NASA study concluded the chance of a failure on the shuttle’s first launch was one in 12, or 8.3 percent. Some of the other early launches were deemed even riskier, about 10 percent, according to the study.
“It is not uncommon for a final system design to present significantly more risk than its original designers expected due to what are known as ‘unknown unknowns,’ ” NASA’s Aerospace Safety Advisory Panel wrote in a report on Jan. 15. The group makes safety recommendations to the U.S. space agency.
At the end of the shuttle’s life, risks had been reduced to about one in 90 per flight. At that rate, 272 U.S. airliners would crash out of the average 24,000 flights a day.
By comparison, there has been one fatal accident on a U.S. passenger carrier since 2009 out of more than 50 million flights, according to the U.S. National Transportation Safety Board.
Tourism rocket explodes in desert, killing 1
MOJAVE, Calif. – A Virgin Galactic space tourism rocket exploded Friday during a test flight, killing a pilot aboard and seriously injuring another while scattering wreckage in Southern California’s Mojave Desert, witnesses and officials said.
The company founded by billionaire Richard Branson would not say what happened other than that it was working with authorities to determine the cause of the “accident.”
“During the test, the vehicle suffered a serious anomaly resulting in the loss of SpaceShipTwo,” Virgin Galactic tweeted.
Ken Brown, a photographer who witnessed the crash, told The Associated Press that SpaceShipTwo exploded after a plane designed to take it to high altitude released it and the craft ignited its rocket motor.
Brown said the wreckage fell in the desert north of Mojave Air and Space Port, where the test flight originated. The area is about 120 miles north of downtown Los Angeles.
There is one fatality and one major injury, California Highway Patrol Officer Jesse Borne said. One person parachuted out, he said.
SpaceShipTwo, which is typically flown by two pilots, was designed to provide a suborbital thrill ride into space before it returns to Earth as a glider.
Friday’s flight marked the 55th for the spaceship, which was intended for tourists.
At 60 feet long, SpaceShipTwo features two large windows for each of up to six passengers, one on the side and one overhead.
Virgin Galactic – owned by Branson’s Virgin Group and Aabar Investments PJS of Abu Dhabi – sells seats on each prospective journey for $250,000, with full payment due at the time of booking. The company says that “future astronauts,” as it calls customers, have visited Branson’s Caribbean home, Necker Island, and gone through G-force training.
Stephen Hawking, Justin Bieber, Ashton Kutcher and Russell Brand are among the celebrities to sign up for flights. Virgin Galactic reports taking deposits totaling more than $80 million from about 700 people.
A related venture, The Spaceship Co., is responsible for building Virgin Galactic’s space vehicles.
During testing for the development of a rocket motor for SpaceShipTwo in July 2007, an explosion at the Mojave spaceport killed three workers and critically injured three others. A California Division of Occupational Safety and Health report said the blast occurred three seconds after the start of a cold-flow test of nitrous oxide – commonly known as laughing gas – which is used in the propulsion system of SpaceShipTwo. The engine was not firing during that test.
Friday’s accident was the second space-related explosion this week.
On Tuesday, an unmanned commercial supply rocket bound for the International Space Station exploded moments after liftoff from a launch site in Virginia. No injuries were reported that accident, which drew criticism over NASA’s growing reliance on private U.S. companies in this post-shuttle era
Virgin Galactic planned to launch space tourism flights from the quarter-billion-dollar Spaceport America in southern New Mexico once it finishes developing its rocket ship.
Christine Anderson, executive director of the New Mexico Spaceport Authority, did not want to comment on the events unfolding Friday in the California desert or what effect they might have on Spaceport America and the future of commercial space travel.
Virgin Galactic is in line to be the main tenant at the spaceport that was built specifically to launch paying customers into space, a dream of Branson’s. His company has repeated pushed back the timetable for when the $250,000 flights were to begin, pointing to delays in development and testing of the rocket ship.
Taxpayers footed the bill to build the state-of-the-art hangar and runway in a remote stretch of desert in southern New Mexico as part of a plan devised by Branson and former New Mexico Gov. Bill Richardson. Critics have long challenged the state’s investment, questioning whether flights would ever get off the ground.
SpaceShipTwo is based on aerospace design maverick Burt Rutan’s award-winning SpaceShipOne prototype, which became the first privately financed manned rocket to reach space in 2004.
Commercial development has been slower than expected. When Virgin Group licensed the technology from Microsoft co-founder Paul Allen, who funded about $26 million for SpaceShipOne, Branson envisioned operating flights by 2007.
