Did Early Feather Unlock Expose SS2 to Too
Much Aerodynamic Pressure? (Source: SPACErePORT)
If the feather mechanism was unlocked before -- rather than after --
the vehicle's high-g turn toward space, the aerodynamic pressure of the
upward turn could have forced the tail/wings toward the feathered
position. This could have torn off the wing sections and flipped the
spacecraft tail first, as seen in this photo
(the bright spot shows the engine burning at the front of the vehicle's
flight path, rather than behind, with the wings broken off on either
side).
This video
shows a 'normal' flight test in September 2013. Notice the feather
unlocking occurs at 0:38, roughly 17 seconds after the engine is fired
and during the vehicle's upward ascent. In last week's failed flight,
the unlocking occurred at nine seconds. The video shows the unlocked
feathers are moved to their upward position at 1:20, at apogee, roughly
one minute after the engine is fired.
Last week's breakup occurred at about 12 seconds after engine ignition.
At this point on the September video, at 0:34, the vehicle was
beginning its upward turn, with the g-forces clearly being felt by the
pilot, considering the strain in his voice. The time of failure seems
to have been near the period of maximum aerodynamic pressure during the
flight. (11/3)
NTSB Making Progress on SS2 Investigation, Premature Feathering Blamed for Breakup (Source: SPACErePORT)
The National Transportation Safety Board (NTSB) seems to be making fast progress with its investigation of the Virgin Galactic accident, thanks in-part to an abundance of data from multiple onboard and external videocameras, telemetry and eyewitness accounts for the test flight. Most of the key parts of the vehicle have been found, including the engine and fuel and oxydizer tanks, all of which were intact with no signs of burn-through. This shifts the focus away from an engine failure.
Instead, they found that the spacecraft's feathering mechanism was unlocked by the co-pilot nine seconds after the engine's ignition. The unlocking normally must be followed by the movement of a lever to initiate the feathering. This is designed to ease the vehicle's descent after reaching apogee, so the unlocking might normally occur later in the flight at a higher altitude (and thinner atmosphere). But the feathering system engaged two seconds after the unlocking, after which the telemetry stream was lost as the vehicle broke up. The NTSB hasn't determined whether the breakup was accompanied by other mechanical failures.
So, some serious questions remain and the investigation will likely continue for months. Why did the feathering occur early? Was it unlocked prematurely (co-pilot error)? Concerns about an engine failure are fading, but excessive shaking/vibration was an issue in previous engine tests with a different fuel mix. Could this have contributed to the feathering mechanical failure and breakup? (11/3)
Virgin Boss Hits Out After Safety
Warning Claim (Source: Phys.Org)
Virgin Galactic boss Richard Branson hit out against "hurtful" critics
and "self-proclaimed experts" on Monday after a rocket scientist said
that the company had ignored safety warnings ahead of the deadly crash
of one of its spacecraft. Branson said the evidence showed there had
been "no explosion" behind the SpaceShipTwo accident in the United
States last Friday.
He vowed to push on with the project, while investigators pored over
the wreckage in the Mojave Desert in California for clues. "I've never
seen such irresponsible innuendo and damaging innuendo," the British
business tycoon told Sky News television, referring to critical press
reports in Britain. "The fuel tanks and the engine were intact, showing
there was no explosion, despite a lot of self-proclaimed experts saying
that was the cause," he said. (11/3)
Virgin Boss Says Galactic Plan Will
‘Move Forwards’ (Source: Aviation Week)
Virgin Galactic founder Richard Branson says that barring the discovery
of insurmountable hurdles resulting from the Oct 31. crash of the
SpaceShipTwo (SS2) prototype spaceplane, the company will continue with
its long running plans to become the world’s first spaceline. When the
accident occurred Scaled Composites was in the final phases of testing
SS2 before handing the vehicle over to Virgin Galactic for the run up
to the start of operational flights from Spaceport America in New
Mexico in 2015. (11/1)
Branson, Allen, Musk, Bezos: Tech
Execs in the Space Race (Source: News.com.au)
The concept of space travel has proved an irresistible allure for many
entrepreneurs who’ve made it in the tech world, and they have been
spurred on by NASA’s increasing reliance on private companies to
conduct space missions. The industry has been rocked by SpaceShipTwo’s
crash coming just days after the explosion of an Orbital Sciences Corp.
commercial supply rocket bound for the International Space Station. But
the race for commercial space travel continues. Here’s
a look at the major tech titans leading the way. (11/3)
Virgin Galactic: Safety Lapse Claims
'Categorically Untrue' (Source: Mashable)
In the days following the fatal crash of Virgin Galactic's SpaceShipTwo
rocket, some voices have emerged questioning its attention to safety, a
claim the company refuted in a statement released on Sunday. "At Virgin
Galactic, we are dedicated to opening the space frontier, while keeping
safety as our 'North Star,'" reads the statement emailed to Mashable
and appearing on the company's website. "This has guided every decision
we have made over the past decade, and any suggestion to the contrary
is categorically untrue." (11/2)
Pilot Error May Have Contributed to
Crash (Source: LA Times)
Two levers were supposed to be pulled when the spacecraft reached Mach
1.4, allowing an action called "feathering" -- which lifts the tail to
slow descent and create drag. Instead, a video in the cockpit and
other data showed that one of the levers was unlocked early at Mach
1.0, NTSB Acting Chairman Christopher Hart told reporters. About two
seconds later, the tail moved into the extended position, even though a
second "feather" handle was not moved, Hart said. "Pilot error is a
possibility," Hart said. "We're a long way from finding cause." (11/2)
Branson’s Space Tourism Shows What
Today’s Obscene Inequality Looks Like (Source: Guardian)
Sub-orbital tourism holds a special place in the unlovely pantheon of
“experience” consumption. The waste of fossil-fuel energy could only be
considered by someone who either didn’t believe in anthropogenic
climate change or didn’t care. The need to see Earth from a distance
with your own eyes, whatever the cost, hints at an interior life as
arid as the surface of the moon.
Why do you need to witness your planet as a dot – for perspective? Why
can’t you quarry these insights from your own imagination? They would
be seriously better off, all 700 of these mega-rich masses (and just
incidentally, I have never been more disappointed in Angelina Jolie).
If Branson’s project tells us very little about the human condition
except for its frivolity and emptiness, this consumer switch – from
stuff to experiences – has more general implications. Neoclassical
economics and, lately, politics have us all characterized as consumers.
We realize our identities with the stuff we buy, having arrived at an
advantageous price through the rigorous pursuit of our own consumer
interests. (11/3)
Virgin Galactic Spaceship Insured for $40-50M Through AIG (Source:
Reuters)
The Virgin Galactic spaceship which crashed on Friday was insured
against losses totalling around $40-50 million, and the lead
underwriter was AIG, two insurance sources said on Monday. AIG declined
to comment. (11/3)
Why Satellite Communication Matters in
India (Source: Business World)
Accounting for approximately 17 percent of the global population, and
with a growing middle class and a large part of the population still
living in rural and remote areas, India presents large market
opportunities for satellite communication services. ISRO could not keep
pace with the rapidly growing demand for satellite capacity and India's
market landscape changed significantly with release of a new satcom
policy in 2000, which allowed a "controlled" entry of foreign satellite
operators.
Based on the finding in our report India Satcom market 2014, the demand
for regular satellite capacity in India has been growing at over 6 per
cent between 2008 and 2013 and now reached 214 transponder equivalents
(36MHz units, a standard industry measurement for satellite capacity
demand). Main growth drivers have been the strong demand for
distribution of channels to cable TV in C-band as well as DTH pay-TV
broadcasting and enterprise VSAT networks in Ku-band. (11/3)
At the Dawn of Space Commercialization
(Source: Albuquerque Journal)
It’s still dawn in the commercial space industry, but the private
sector is rapidly taking control of government missions as new,
innovative companies blaze fresh paths to the stars. “The rules of the
game are changing,” said George Nield, the FAA’s associate
administrator for commercial space transportation. “Twenty years ago
there was little indication of commercial space at all. But today we
can see a whole range of commercial space activities emerging.” Click here.
(11/3)
Orlando Lunar XPRIZE Competitor Adds
Australian Sponsor (Source: ESF)
Earthrise Space Foundation (ESF) has added Australian software company
Altium as a gold level sponsor. Through a generous licensing agreement,
estimated at $50,000, the foundation will now have access to the Altium
Designer software package, providing a cutting edge electronics
development tool for ESF students. Altium specializes in PC-based
electronics design software for engineers and is a global leader in
Printed Circuit Board (PCB) design software. Altium Designer is an
electronic design automation software package.
ESF is committed to the research and development of spacecraft and
spacecraft systems in Central Florida and is the host of Team Omega
Envoy, a group competing for the $30 million Google Lunar XPRIZE.
(10/14)
Virgin Galactic's Whitesides Reacts to
Safety Claims (Source: AFP)
Virgin Galactic chief executive George Whitesides also questioned the
safety claims, telling the Financial Times that differences of opinion
were common in the world of space flight development. "In the space
community, you will be able to find people who have favorite
technologies of different types. One group will say their type of
technology is better than another," the paper quoted him as saying. "We
pay a lot of attention to the several hundred engineers that we have on
staff, and other expert consultants we've talked with about our
technologies." (11/2)
Virgin Galactic Crash Major Setback
for Spaceport America (Source: Albuquerque Journal)
Before last week's crash, Virgin Galactic already had delayed launch of
commercial operations in New Mexico during the last few years pending
the successful completion of testing and development of the rocket,
known as SpaceShipTwo, at the Mojave Air and Space Port. Now, with that
rocket destroyed and construction of a second ship underway but far
from finished, it’s unclear how long it may take Virgin to move from
research and development in California to commercial operations in New
Mexico.
A statement from the New Mexico Spaceport Authority late Friday
afternoon expressed the state’s condolences. “We just feel so bad for
the pilots and their families,” Spaceport America Executive Director
Christine Anderson told the Journal. “It’s been a really bad day.”
Anderson said it’s too early to speculate on the accident’s impact on
Virgin operations at the Spaceport, but she said the commercial space
industry will move forward.
During hearings at the state Legislative Finance Committee this week,
Spaceport executives said they would face a $1.5 million budget
shortfall in fiscal year 2015 if Virgin didn’t begin commercial
launches by next July. That’s because the Spaceport needs to earn
launch fees from Virgin and revenue from the tourists to meet its
operating expenses. Given Friday’s catastrophe, it may be well into
2016 or beyond before Virgin could consider commercial launches in New
Mexico. (11/2)
Thoughts on the SS2 Crash
(Source: Dennis Wingo)
Burt Rutan with the original Spaceship 1 brought in the hybrid engine
design SPECIFICALLY because it was sold to him as being the safest type
of engine. A hybrid engine with a solid fuel and a liquid oxidizer has
the ability to be shut down like a fully liquid engine, without some of
the problems that come from a fully liquid or solid design.
That was the theory. The truth of the matter is that there is no such
thing (at our current level of technical maturity) as a perfectly safe
rocket engine. ALL rocket engines are an exercise in design compromises
between cost, operability, and complexity as integrated into the larger
system. Click here.
(11/2)
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