Monday, November 03, 2014

Scaled Composites Model 339 SpaceShipTwo, N339SS, Scaled Composites: Accident occurred October 31, 2014 in Mojave, California

FAA  Flight Standards District Office: FAA Van Nuys FSDO-01 

MOJAVE, Calif.—An improper pilot command preceded the violent in-flight breakup of Virgin Galactic LLC’s experimental rocket ship Friday, according to federal safety investigators probing the fatal accident.

In a press briefing Sunday night, the National Transportation Safety Board said the craft’s co-pilot prematurely deployed movable tail surfaces, which was followed seconds later by the disintegration of the 60-foot-long SpaceShip Two.

The co-pilot died in the accident, and the other pilot was severely injured.

During Sunday’s news conference, acting NTSB Chairman Christopher Hart said investigators are still trying to understand reasons for the co-pilot’s actions. “We are a long way from finding cause,” he said.

But with images provided by half a dozen onboard video cameras—and large amounts of data streamed down to the ground before the accident—the safety board already has a good early indication of what transpired.

Mr. Hart said the propulsion system operated normally until the in-flight breakup, and the rocket motor and fuel tanks were found intact in the wreckage.

Without specifically identifying the co-pilot’s actions as the cause of the crash, Mr. Hart told reporters the safety board planned to examine pilot training, the company’s safety culture and whether there was undue pressure on senior officials to accelerate test flights.

The ship’s tail surfaces—called feathers—are designed to be deployed only after the rocket motor is finished burning, to allow the craft to glide to a safe landing. The feathers are supposed to activate only after two separate levers in the cockpit are moved.

But on Friday, Mr. Hart said, the tail surfaces deployed without the second lever being moved.

Investigators haven’t yet interviewed the surviving pilot, who is hospitalized, and it isn’t clear when doctors will give the green light for that to happen.

The safety board also is evaluating recordings of cockpit conversations on the accident flight, but Mr. Hart declined to discuss their contents.

One of the key issues still left unanswered by the board is whether Virgin Galactic, from the beginning, incorporated design safeguards to prevent this type of premature deployment of the feathers, or if protections failed to operate properly.

If it turns out that a structural failure is behind the crash, that could force Virgin Galactic to redesign large portions of the rocket ship—a potentially more arduous and time-consuming task for the company than altering the engine. In theory, it could affect the size of the craft and the number of passengers it can carry.

The disaster, coupled with the explosion earlier last week of an unmanned Orbital Sciences Corp. cargo rocket destined for the international space station, has set back the ambitious timetables embraced by space-tourism proponents and other commercial ventures seeking to get beyond Earth’s atmosphere. Some in the industry predict difficulties obtaining additional private-equity funding for startup ventures, while others worry about nagging propulsion problems and public confidence.

“Recent events bring home the reality that we’re in a very dangerous phase” of pursuing space activities relying on the private sector, said Howard McCurdy, a space history expert at American University. Launching rockets and vehicles “is always a very risky business,” he said, and no amount of ground tests “can duplicate the aerodynamic stresses and other conditions” of actual space flight.

Virgin Galactic had initially hoped to start commercial service by 2008, but persistent development and testing challenges have repeatedly pushed back the date. Before the accident, company officials were talking about inaugurating service by early 2015, with company founder Sir Richard Branson and members of his family slated to take the first ride. Now, the initial launch date is uncertain because the probe is likely to stretch for many months.

How much the fledgling industry is set back may depend on what investigators determine caused the two accidents. Some industry officials and analysts predict that Virgin Galactic’s fatal mishap may have a long-term residual impact as dramatic as the fallout from the 2003 in-flight breakup of the space shuttle Columbia, which killed all seven crew members.

“It’s clearly bad news for commercial space,” said one veteran industry official affiliated with another commercial space company. “But from the beginning, people recognized a fatal event on some spacecraft was inevitable.”

Late Sunday, Virgin Galactic said it wasn’t “in a position to comment on the incident itself or the test flight,” and directed all questions to the NTSB. The statement also said that safety considerations “guided every decision we have made over the past decade, and any suggestion to the contrary is categorically untrue.”

Earlier Sunday, George Whitesides, Virgin Galactic’s chief executive, defended the company’s safety procedures and indicated that the rocket motor on the craft that crashed was a derivative of a design that had been successfully tested on the ground and in the air for years.

“At the end of the day, safety of our system is paramount,” he said in an interview. “The engineers and the flight-test team have the final authority” to determine when and how experimental flights are conducted.

Virgin Galactic has pledged to cooperate fully with the probe, which also includes experts from the Federal Aviation Administration and Scaled Composites, a Northrop Grumman Corp. unit that designed and is testing the Virgin crafts—SpaceShip Two and its carrier aircraft, dubbed WhiteKnight Two. The pilots on Friday’s test flight were Scaled Composites employees.

Mr. Whitesides, a former senior NASA official, is in charge of the roughly $500 million project intended to take passengers on suborbital flights for more than $200,000 each. He said last week’s test flight wasn’t rushed. “I strongly reject any assertion that something pushed us to fly when we weren’t ready,” he said.

SpaceShip Two’s fuel tanks and engine were recovered largely intact. The hybrid motor fueled by nitrous oxide and a plastic-based compound were found some 5 miles from where large sections of the tail first hit the ground. Sections of the fuselage, fuel tanks and cockpit were located some distance from the engine itself.

The condition and location of various pieces of the wreckage suggest there was no propulsion-system explosion before the craft started coming apart miles above California’s Mojave Desert, according to air-safety experts who have reviewed the images.

“It’s hard to figure how an engine explosion” could produce such a debris field, said John Cox, an industry consultant and former accident investigator for the Air Line Pilots Association.

The rocket ship was equipped with six onboard video cameras and many sensors feeding data to the ground. The flight also was followed by radar, and was filmed from the ground and by a plane flying close by.

SpaceShip Two’s rocket motor received considerable attention immediately after the accident. Industry officials and news reports concentrated on the fact that it was burning a new type of plastic-based fuel for the first time in flight.

The closely held company struggled through years of propulsion problems before switching to the redesigned engine and reformulated fuel in May. The previous engine, which burned a rubber-based fuel, produced unexpected vibrations and inadequate power to blast SpaceShip Two and its anticipated eight occupants 62 miles above the Earth.

The new engine-fuel combination was tested on the ground about a dozen times in the months leading up to Friday’s flight.

The Virgin Galactic team also had struggled with flight-control problems. In 2011, chief pilot David Mackay told The Wall Street Journal that during one unpowered test glide to Earth, the twin tails of SpaceShipTwo stalled and the craft descended more quickly than normal.

On Sunday, Mr. Whitesides said the 2011 incident was the only major flight-control problem Virgin Galactic encountered. He said engineers had fixed “the tail stall via a modification” to a control surface.


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