Copyright Armadillo Aerospace A fully reusable launch system is the key to providing
the low cost access to Space that is required to bring
about extensive human exploration and settlement of
the solar system.
The Space Shuttle succeeded technically as a partially
reusable launcher but failed miserably economically.
It requires several thousand support personal and 2
months or more to rebuild a Shuttle for its next launch.
Shuttle launch costs are roughly $20,000/kg, which is
actually higher than most expendable launchers.
During the 1990s a number of RLV (Reusable Launch Vehicle)
startup companies appeared due to the promise of a lucrative
market for launching spacecraft for the low earth orbit
communications constellations that were then in development.
Unfortunately, the failures of Iridium, Globalstar,
and the other constellations pulled the rug out from
under these space transport companes and several disappeared
or went into long-term limbo.
The failures of several NASA projects, such as the
X-33
and X-34,
also discouraged government investment in RLV technology.
Bad design and poor management had more to do with these
failure than technical challenges but they nevertheless
convinced many in NASA and elsewhere that RLV technology
was not at hand.
Note: The Kistler
Aerospace K-1 vehicle, intended for the LEO constellation
replacement markets, was 75% complete when funding
ran out around 2000. No one has shown any technical
reason that the vehicle would not work if completed.
It is an existence proof that two-stage fully reusable
vehicle technology is in fact feasible now. NASA has
selected the Rocketplane-Kistler team as one of the
contractors for the COTS program to demonstrate commercial
cargo delivery to the ISS. So we should finally discover
if the K-1 can fulfill its design goals.
Currently (circa 2006), the most intense RLV development
activity is taking place in the suborbital
spaceflight area. These vehicles are primarily intended
for space tourism but will also take over many of the
scientific applications carried out by sounding rockets.
The resources about such RLV projects & technology
present, past and future. The T
sign indicates that a project has an entry in the RLV
Table.
Also, included are in-space vehicles (e.g. OSP,
X-37)
which can be launched in different ways. For example,
such a vehicle might be released in space from a shuttle
or launched on top of an expendable. They might operate
in space indefinitely or, in other cases, return to
earth to be used again for crew transport.
See the New
Launch Technologies section for resources related
to new conventional expendable and partially reusable
rocket vehicles. It also offers information and links
dealing with non-rocket types of transport such as space
elevators and laser
launchers. See the Hypersonic
Transport sections for resources related to scramjet
vehicles.
Note:
Many people complain that the term reusable launch
vehicle is clumsy and archaic. We don't, after
all, call airliners reusable takeoff vehicles!
The RLV term helps to perpetuate the myth that every
flight of a rocket powered vehicle is a lucky shot
and that such craft will never attain the high reliability
and lost cost operations of airliners.
However, in the next few years we will see robust
and reliable rocket powered suborbital vehicles begin
making daily flights, even multiple flights in a day.
It will then seem rather silly to talk about countdowns
and launches. They will simply takeoff when they are
ready, just like any other flying vehicle.
There is not been put forward a generally accepted
substitute term. The SpaceShipOne
success argues for spaceship but it still isn't
generally accepted. I'm gradually replacing the RLV
terminology here with space transport. However,
some other term, such as spaceliner, rocketship, etc
, may eventually become the more popular choice.
See the RLV
& Space Transport News section for
the latest on the development of RLV and other space
transportation technologies.
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