I've read that the STS programme was, overall, a failure.
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The program started in the late 1960s and has dominated NASA's manned operations since the mid-1970s. According to the Vision for Space Exploration - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Moon.mars.cover.jpg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/7/78/Moon.mars.cover.jpg/220px-Moon.mars.cover.jpg"@@AMEPARAM@@commons/thumb/7/78/Moon.mars.cover.jpg/220px-Moon.mars.cover.jpg (http://en.wikipedia.org/wiki/Vision_for_Space_Exploration) spacecraft, but budget cuts have placed full development of the Orion craft in doubt.
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The shuttle program, which was scheduled for mandatory retirement in 2011, saw the final launch with Atlantis launching on July 8, 2011, in accord with the directives President George W. Bush issued on January 14, 2004 in his Vision for Space Exploration.[9] (http://en.wikipedia.org/wiki/Space_Shuttle_program#cite_note-bushvision-8) The shuttle's planned successor was to be Constellation program - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Constellation_logo_white.svg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/2/26/Constellation_logo_white.svg/250px-Constellation_logo_white.svg.png"@@AMEPARAM@@commons/thumb/2/26/Constellation_logo_white.svg/250px-Constellation_logo_white.svg.png (http://en.wikipedia.org/wiki/Project_Constellation); however, in early 2010 the Obama administration asked Congress to instead endorse a scaled-back plan with heavy reliance on the private sector.
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The total cost of the shuttle program had been $145 billion as of early 2005, and as of 2011, had risen to $196 billion.[4] (http://en.wikipedia.org/wiki/Space_Shuttle_program#cite_note-AP_July_2011-3) NASA had originally calculated the total cost of the program to be just $90 billion.[4] (http://en.wikipedia.org/wiki/Space_Shuttle_program#cite_note-AP_July_2011-3)
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Early cost estimates of $118 per pound ($260/kg) of payload were based on marginal or incremental launch costs, and based on 1972 dollars and assuming a 65,000 pound (30 000 kg) payload capacity.[26] (http://en.wikipedia.org/wiki/Space_Shuttle_program#cite_note-25)[27] (http://en.wikipedia.org/wiki/Space_Shuttle_program#cite_note-costbenefit-26) Correcting for inflation, this equates to roughly $36 million incremental per launch costs; today's actual incremental per launch costs of $60 million are about two thirds more than this.
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Criticism of the Space Shuttle program stems from claims that the Space Shuttle program - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Shuttle_Patch.svg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Shuttle_Patch.svg/250px-Shuttle_Patch.svg.png"@@AMEPARAM@@commons/thumb/5/5c/Shuttle_Patch.svg/250px-Shuttle_Patch.svg.png (http://en.wikipedia.org/wiki/Space_Shuttle_program) expendable launchers, still largely based on the design that dates back to 1965, are said to cost as little as $110 million[5] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-4), or around $5,000/kg to LEO. This should be further contrasted with the originally envisioned costs of $118 per pound of payload in 1972 dollars ($1,400/kg, adjusting for inflation to 2011).[6] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-century_of_flight-5)
It failed in the goal of achieving reliable access to space, partly due to multi-year interruptions in launches following Shuttle failures.[7] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-Folly-6) NASA budget pressures caused by the chronically high NASA Space Shuttle program costs have eliminated NASA manned space flight beyond low earth orbit since Apollo, and severely curtailed more productive space science using unmanned probes.[8] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-7) NASA's promotion of and reliance on the Shuttle slowed domestic commercial Expendable launch system - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Dawn_launch.jpg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Dawn_launch.jpg/220px-Dawn_launch.jpg"@@AMEPARAM@@commons/thumb/d/d9/Dawn_launch.jpg/220px-Dawn_launch.jpg (http://en.wikipedia.org/wiki/Expendable_launch_vehicle).[9] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-8)
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Some shuttle features initially presented as important to Space Station support have proved superfluous:
As the Russians demonstrated, capsules and unmanned supply rockets are sufficient to supply a space station.
NASA's initial policy of using the Shuttle to launch all unmanned payloads declined in practice, and eventually was discontinued. Expendable launch system - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Dawn_launch.jpg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Dawn_launch.jpg/220px-Dawn_launch.jpg"@@AMEPARAM@@commons/thumb/d/d9/Dawn_launch.jpg/220px-Dawn_launch.jpg (http://en.wikipedia.org/wiki/Expendable_launch_system) (ELVs) proved much cheaper and more flexible.
Following the Challenger disaster, use of the Shuttle to carry the powerful Liquid-propellant rocket - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:NASA_bipropellant_Lrockth.png" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/3/3d/NASA_bipropellant_Lrockth.png/350px-NASA_bipropellant_Lrockth.png"@@AMEPARAM@@commons/thumb/3/3d/NASA_bipropellant_Lrockth.png/350px-NASA_bipropellant_Lrockth.png (http://en.wikipedia.org/wiki/Liquid_rocket) Centaur http://en.wikipedia.org/wiki/Centaur_%28rocket_stage%29 upper stages planned for interplanetary probes was ruled out for Shuttle safety reasons.[20] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-19)[21] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-20)
The Shuttle's history of unexpected delays also makes it liable to miss narrow Launch window - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Launch_window).
Advances in technology over the last decade have made probes smaller and lighter, which are less expensive and perceived to be more reliable than the Shuttle.
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Opinions differ on the lessons of the Shuttle. While it was developed within the original cost and time estimates given to President Richard M. Nixon (http://en.wikipedia.org/wiki/Richard_M._Nixon) in 1971, the operational costs, flight rate, payload capacity, and reliability have been much worse than anticipated.[24] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-23) A year before STS-1 (http://en.wikipedia.org/wiki/STS-1)'s April 1981 launch, The Washington Monthly - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/The_Washington_Monthly) accurately forecast many of the Shuttle's issues, including an overambitious launch schedule and the consequent higher-than-expected marginal cost per flight; the risks of depending on the Shuttle for all payloads, civilian and military; the lack of a survivable abort scenario if a Solid Rocket Booster were to fail; and the fragility of the Shuttle's thermal protection system.[25] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-easterbrook198004-24)[26] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-day20110627-25)
In order to get the Shuttle approved, NASA over-promised its economies and utility. To justify its very large fixed operational program cost, NASA first forced all domestic, internal, and United States Department of Defense - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:United_States_Department_of_Defense_Seal.svg" class="image"><img alt="United States Department of Defense Seal.svg" src="http://upload.wikimedia.org/wikipedia/commons/thumb/e/e0/United_States_Department_of_Defense_Seal.svg/140px-United_States_Department_of_Defense_Seal.svg.png"@@AMEPARAM@@commons/thumb/e/e0/United_States_Department_of_Defense_Seal.svg/140px-United_States_Department_of_Defense_Seal.svg.png (http://en.wikipedia.org/wiki/United_States_Department_of_Defense) and commercially available boosters, costs might have been lower, freeing funds for manned exploration and more unmanned space science. In particular, http://en.wikipedia.org/wiki/NASA_administrator Michael D. Griffin (http://en.wikipedia.org/wiki/Michael_D._Griffin) argued in a 2007 paper that the Saturn program, if continued, could have provided six manned launches per year two of them to the moon at the same cost as the Shuttle program, with an additional ability to loft infrastructure for further missions:
If we had done all this, we would be on Mars today, not writing about it as a subject for the next 50 years. We would have decades of experience operating long-duration space systems in Earth orbit, and similar decades of experience in exploring and learning to utilize the Moon.[27] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-26)
While the general concept of a reusable manned launch vehicle was good, some have argued that the shuttle program is flawed.[28] (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program#cite_note-27) In the beginning of the program, to achieve a reusable vehicle with early 1970s technology entailed several design decisions that compromised operational reliability and safety. For example, an early point in the design phase, reusable main engines became a priority. This necessitated that they not burn up upon atmospheric reentry, which in turn made mounting them on the orbiter itself (the one part of the shuttle system where reuse was paramount) a seemingly logical decision. However, this had the following consequences:
a more expensive 'clean sheet' engine design was needed, using more expensive materials, as opposed to existing and proven off-the-shelf alternatives (such as the Saturn V mains);
increased ongoing maintenance costs related to keeping the reusable SSMEs in flying condition after each launch, costs which in total may have exceeded that of building disposable main engines for each launch;
less absolute tonnage available to be lifted into space, since the mass of the SSMEs attached to the orbiter necessarily cut into the craft's 'payload budget' (more payload launched at any one time, by definition, reduces launch costs per pound).
Criticism of the Space Shuttle program - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:SpaceShuttleGroundProcessingVision.jpg" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/4/42/SpaceShuttleGroundProcessingVision.jpg/200px-SpaceShuttleGroundProcessingVision.jpg"@@AMEPARAM@@commons/thumb/4/42/SpaceShuttleGroundProcessingVision.jpg/200px-SpaceShuttleGroundProcessingVision.jpg (http://en.wikipedia.org/wiki/Criticism_of_the_Space_Shuttle_program)