AIRCRAFT EXPERIMENTAL
SCALED COMPOSITES 339 CRASHED ONTO THE KOEHN DRY LAKE BED SHORLY AFTER
SEPARATION FROM MOTHERSHIP WHITEKNIGHT 2 N348MS, THERE WERE TWO PERSONS
ON BOARD, 1 WAS FATALLY INJURED 1 SUSTAINED SERIOUS INJURIES, MOJAVE, CA
FAA Flight Standards District Office: FAA Van Nuys FSDO-01
http://registry.faa.gov/N339SS
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.
-Source: http://online.wsj.com
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