fact, we probably performed better
than the original test standards
were meant to be. We deem this to
be a significant success.”
Although the flight did not end as
everyone had hoped, the incident
provided a wealth of valuable data
showing how strong the vehicle is.
“The entire interior of the
vehicle, the pressure vessel as
we call it, or crew compartment,
was completely untouched by
the incident,” said Sirangelo. “All
systems were fully operational, there
was no damage whatsoever to any
of the components of the vehicle.
All the flight computers continued
to work, and they are still working,
and there was no damage to any
of the sensitive parts of the vehicle
– which tells us that the composite
structure and the airframe is actually
“As we stand right now we believe
we have the data, we looked at all
the data and its almost exactly as
was predicted by our computing
models,” added Sirangelo. “We
were so successful that we actually
received all of the data we think we
needed for testing.”
Even though the investigation
of the landing gear problem is
ongoing, the data points to a
mechanical failure, possibly with
the door or latch—as none of the
primary systems that gave the
commands that control the flight
failed or had any problems. Both
landing gear systems—main gear
and nose gear—are connected;
they are mirror images of each
other, and the right landing gear
deployed as expected and was
fully functional. Had the spacecraft
in this case was a simulated thermal
protection system (TPS). That
actually effectively cushioned the
vehicle as it went through its flight
off the runway, and while that was
damaged its a fairly insignificant
part of it.”
“The core structure, all the flight
controls, the rudders, the airlons,
all those are still attached and
working,” added Sirangelo. “We
did lose some of the protective
coating and shell of the vehicle
and sustained some minor damage
to some of the composites and
the structure underneath. The
very strong front nose skid actually
continued to hold the vehicle up
and do exactly what it was designed
to do, and it is fully functional and
working right now.”
The Dream Chaser, described
design or software caused the
problem, it would have affected
both the right and left main landing
gear.
“The vehicle has all of its
components, nothing was lost – the
tail, the rudders, the entire structure
of the vehicle is with us and sound,”
added Sirangelo. “The one landing
gear in question is still attached
to the vehicle, it did eventually
deploy, obviously not properly but
its still there, we didn’t lose it. The
vehicle is surrounded by a very
strong composite structure shell,
which is where all the important
materials
(computers,
crew
compartment, etc) would be, and
then it is surrounded by over six
inches of protective layer – which
by many simply as a “mini space
shuttle,” is a lifting body human
spacecraft designed to carry as
many as seven astronauts, and it
is the only spacecraft under the
Commercial Crew Development
Round 2 (CCDev2) agreement with
NASA’s Commercial Crew Program
(CCP) that is winged and designed
to land on any conventional runway
capable of handling commercial
traffic.
“NASA Langley did a lot of
research on the vehicle in the
80’ and 90’s, based off a Russian
heritage design called the Bor 4”
said former astronaut and SNC
Space Exploration Systems Vice
President James Voss in 2012. “They
did wind tunnel analysis, a lot of
Artist renderings of the
Dream Chaser docked
at the ISS (right photo),
and being prepared to
launch atop an Atlas V
rocket (following page).
Images: Sierra Nevada Corp.
quite stable and quite strong for
what we needed to accomplish.”
The test article used to conduct
ALT-1 in late October was only
meant to conduct two autonomous
flights before being sent back to
SNC’s headquarters to be reworked
for piloted flight testing. If October’s
flight test produced all of the data
SNC needs—and the company
believes it did—then they can skip
a second autonomous flight test all
together.
The landing gear itself was never
intended as a permanent fixture, as
it is a modified version of the gear
used on the USAF F-5E Tiger fighter
aircraft. Future Dream Chasers
will use landing gear with electric
actuators.
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