up to 120,000 pounds of axial thrust (16,000 pounds of
thrust each, compared to 100 pounds of thrust each
with the original Draco thrusters). The engines also come
in pairs, so if one engine fails the other can increase its
thrust to compensate for the engine that is not firing.
The SuperDraco engines on the Dragon V2 are also
the first fully 3-D printed engines intended for space.
The chamber is regeneratively cooled and printed in
Inconel, a high-performance superalloy that offers both
high strength and toughness for increased reliability;
they will become the first printed rocket engines
ever used in spaceflight. It was only a couple days
ago that SpaceX completed qualification testing for
the SuperDraco thruster at the company’s Rocket
Development Facility in McGregor, Texas, which
included testing across a variety of conditions including
multiple starts, extended firing durations, and extreme
off-nominal propellant flow and temperatures.
“Through 3-D printing, robust and high-performing
engine parts can be created at a fraction of the cost
and time of traditional manufacturing methods,”
said Musk. “SpaceX is pushing the boundaries of
what additive manufacturing can do in the 21st
century, ultimately making our vehicles more
efficient, reliable and robust than ever before.”
An artist’s rendering of Sierra Nevada’s Dream Chaser spacecraft alongside
Space Shuttle Atlantis at the Shuttle Landing Facility in Florida. Credit: SNC
Where does this leave
Sierra Nevada’s Dream Chaser?
As with any competition, there must be a loser. Sierra
Nevada’s Dream Chaser “mini space shuttle” did not
secure a CCtCap award from NASA. However, that
does not mean we will never see a Dream Chaser
fly, it just means we won’t see NASA giving them
extra money to continue development to serve the
space agency’s agenda for contracting with private
companies for crew transport to and from the ISS.
However, soon after the award decision was
announced Sierra Nevada Corporation (SNC)
filed a “legal challenge” with the Government
Accountability Office (GAO) protesting NASA’s
selection of Boeing and SpaceX, stating that, “NASA’s
own Source Selection Statement and debrief
indicate that there are serious questions and
inconsistencies in the source selection process.”
Pursuant to the GAO protest filed by SNC on Sept. 26
NASA was forced to issue a “stop work order” instructing
both Boeing and SpaceX to stop performance of their
newly awarded Commercial Crew contracts. However,
a couple weeks later NASA decided to exercise their
“statutory authority” and press on with Boeing and
SpaceX contracts despite SNC’s protest with the GAO.
“The agency recognizes that failure to provide the
CCtCap transportation service as soon as possible
poses risks to the ISS crew, jeopardizes continued
operation of the ISS, would delay meeting critical crew
size requirements, and may result in the U.S. failing to
perform the commitments it made in its international
agreements. These considerations compelled NASA
to use its statutory authority to avoid significant
adverse consequences where contract performance
remained suspended. NASA has determined that it
best serves the United States to continue performance
of the CCtCap contracts that will enable safe and
reliable travel to and from the ISS from the United
States on American spacecraft and end the nation’s
sole reliance on Russia for such transportation.”
Regardless of the outcome between SNC and NASA,
SNC Space Systems VP Mark Sirangelo has made it
loud and clear that the company is ready to move
forward with development of the Dream Chaser without
NASA, as long as there is a business case for it, and that
business case may come in the form of international
cooperation with the European Space Agency (ESA)
and the Japan Aerospace Exploration Agency (JAXA).
Sierra Nevada has already begun to build their first
Dream Chaser for an inaugural orbital flight test atop a
ULA Atlas-V rocket in late 2016, and they have already
purchased the Atlas-V for that flight. Whether that flight
actually occurs though we will have to wait and see.
“Our destiny is set. Our course is laid out before
us. And we are following it,” added Bolden after
announcing NASA’s decision. “We hope the
American people will be inspired to join us on this
next great, ambitious leg of humanity’s journey
farther into our solar system than ever before.”
“I can’t put into words what it will feel like to see
years of hard work payoff when that first CST-100
launches,” added Boeing’s Tony Castilleja at the end
of our most recent conversation. “When we launch
the CST-100 on that Atlas-V rocket I can’t wait to
look to the left of me, to the right of me, and see the
friends and the passion that each and everyone put
together to launch this off, and I can’t wait to see
our astronauts return home on our vehicle safely.”
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