An artist’s rendering of the SpaceX Dragon V2 capsule and service module in orbit and heading to the International Space Station. Credit: SpaceX
dedicated Dragon resupply missions to the ISS by 2016,
missions which promise to haul a total of 44,000 pounds
of equipment and supplies to the orbiting outpost.
Dragon V1 was the first commercial spacecraft to visit
the ISS, and the first commercial spacecraft to return to
Earth from orbit. It has flown to, and from, the ISS four
times, starting with the inaugural Commercial Orbital
Transportation Services (COTS) Demo mission in May 2012
and followed by the dedicated CRS-1 and CRS-2 missions
in October 2012 and March 2013, the CRS-3 mission last
April, and most recently the CRS-4 mission just last month.
However, Elon Musk has always said he wants
to bring American human spaceflight capability
back to the nation and give humanity the means to
become a multi-planet species, at much cheaper
than any government can do, and even though
the Dragon V1 does have a life-support system it’s
not one that can last for a long time or carry a lot
of people. That’s where the Dragon V2 comes in,
and its landing method will be quite different, too.
“Dragon V2 still retains the parachutes of Dragon
V1, but V2 will be able to land anywhere on land
propulsively, and do so anywhere on Earth with the
accuracy of a helicopter, which is something I think a
modern spaceship should be able to do,” said Musk.
“When Dragon V2 reaches a particular altitude a few
miles before landing it will test the engines and verify
that all the engines are working before proceeding
to a propulsive landing, and if there is any anomaly
detected with the engines or propulsion system it will
then deploy the parachutes to ensure a safe landing,
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even in the event that the propulsion system is not
working. All around I think it’s really a big leap forward
in technology, it really takes things to the next level.”
“Even after starting the propulsion system it can
afford to lose up to two engines and still land safely,”
added Musk. “After the engines are started it will then
deploy the landing legs for a soft landing. This is really
important, apart from the convenience of the landing
location, because it enable rapid reusability of the
spacecraft, you can just reload propellants and fly again.
This is extremely important for evolutionizing access to
space because as long as we continue to throw away
rockets and spacecraft we will never truly have access
to space, it will always be incredibly expensive.”
Musk offered the following scenario for comparison:
“If aircraft were thrown away after each flight then
nobody would be able to fly, or very few, maybe a
small number of customers. The same is true of rockets
and spacecraft, so that’s really why it’s so important
to be able to land propulsively, land on land and be
able to reload propellants and take off again.”
The biggest upgrade, at least from a propulsion
standpoint, is the addition of the SuperDraco engines, a
“superpowered” version of the Dragon V1 Draco engines
used to maneuver in space and control the spacecraft’s
trajectory during reentry. Dragon V2 will still use the
original Draco thrusters for maneuvering in space, but the
V2’s SuperDraco thrusters will serve both as part of the
vehicle’s launch escape system and enable propulsive
landing on land. A total of eight SuperDraco’s are built
into the side walls of the Dragon V2 and will produce
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