Unfulfilled expectations: what is planned and what happened in the "Space Shuttle"




One of these days happened to notice that five times in comments posted on the question of the degree of success of the program "Space Shuttle". Such regularity issues requires a full article. In it I will try to answer the questions:
  • What are the goals to put the program "Space Shuttle»?
  • What was the result?

    Subject reusable media is very extensive, so in this article I specifically limited to these issues.

    What is planned? H4>
    The idea of ​​the shuttle occupied the minds of scientists and engineers in the United States with more 50s. On the one hand, I'm sorry to break the ground dropped the exhaust stage. On the other hand, the device that combines the properties of aircraft and spacecraft will be in line with the Jets philosophy where reusable natural. Various projects were born: X-20 Dyna Soar , Recoverable Orbital Launch System (later Aerospaceplane). In the sixties, this inconspicuous enough activity continued in the shadow program "Gemini" and "Apollo." In 1965, two years before the flight "Saturn-V», was established a subcommittee on technology reusable launch vehicles at the Coordinating Council for Air and Space Operations (which was attended by the US Air Force and NASA). The result of this work was a document issued in 1966, stating the need to overcome serious difficulties, but was promised a bright future for Earth orbit. At the Air Force and NASA had a different vision of the system and different requirements, so instead of one project were presented ideas ships of various layout and degree of reusability. After 1966 NASA began to think about creating a space station. This implies the need to station a large number of delivery of cargo into orbit, which in turn raises the question of the cost of such delivery. In December 1968, a working group, which was engaged in the so-called Joint Machinery launch and landing Integral Launch and Reentry Vehicle (ILRV). Report this group was submitted in July 1969 and claimed that ILRV should be able to:

    • Implementing the space station
    • Run and return from orbit satellites
    • in orbit boosters and payload
    • in orbit fuel (for subsequent charging other devices)
    • maintain and repair satellites in orbit
    • Provide short manned mission In parallel, in February 1969, President Nixon established a working group whose task was to determine the direction of movement in space exploration. The result of this group was the recommendation of creating a reusable spacecraft that would:
      • Become a fundamental improvement of existing space technology in terms of value and volume into orbit
      • transport people, cargo, fuel, other ships, boosters and stuff into orbit as the plane - regular, cheap often and a lot.
      • Must be versatile for compatibility with a wide range of civilian and military payloads.

        This combination was the theoretically cheap to operate. However, the requirement of a large payload makes the system too much (and, hence, expensive). In addition, the military wanted the possibility of horizontal maneuvers of 3000 km for landing at the Baikonur launch on the first turn of the a polar orbit abbr>, which limited engineering solutions (for example, it becomes impossible straight wings).


        Judging by the signature «high cross-range» (large horizontal maneuver) This picture is liked war i>

        The final layout is very strongly dependent on the following requirements:
      • The size and capacity of the cargo compartment
    • The amount of horizontal maneuver
  • Engines (type, traction and other parameters)
A method of planting (on engines or planning) The materials used The cargo compartment 4, 5h18, 2 m (ft 15h60) 30 tons into low Earth orbit, 18 tonnes into polar orbit Ability to maneuver a horizontal distance of 2000 km
 In around 1970 it became clear that the space station and the shuttle while money is not enough. And the station for which the shuttle had to haul cargo, has been canceled.
At the same time in an engineering environment reigned unbridled optimism. Based on the experience of operation of the experimental rocket planes ( X-15 ), engineers predicted cost reduction kilograms into orbit two orders of magnitude ( a hundred times). At a symposium on the program "Space Shuttle", which took place in October 1969, the "father" of the shuttle George Müller a > said:

«Our goal - to reduce the cost of a kilogram into orbit from $ 2,000 for a Saturn-V to the level of $ 40-100 per kilogram. This we will open a new era of space exploration. Challenges for the future weeks and months for this symposium, for the Air Force and NASA is to provide confidence that we can do it. » Blockquote>
BE Chertok in the fourth part of "Rockets and People" gives some other figures, but of the same order:

For different options based on the "Space Shuttle" predicted achievement breeding value in the range from 90 to 330 dollars per kilogram. Furthermore, it was assumed that the "Space Shuttle" second generation will reduce these numbers to 33-66 dollars per kilogram. Blockquote>
According to the calculations Mueller shuttle launch will be worth $ 1-2, 5 million (compared to $ 185 million. For the Saturn-V).
Were also carried out sufficiently serious economic calculations, which show that in order to at least equal to the cost of the carrier rocket "Titan-III» in a direct comparison of prices excluding discount abbr>, the shuttle need to start 28 times a year. For the fiscal 1971, President Nixon has allocated $ 125 million for the production of disposable rockets that was 3, 7% of the budget NASA. That is, if the shuttle was already in 1971, he would have saved only 3, 7 percent of the budget NASA. Nuclear physicist Ralph Lapp (Ralph Lapp) found that during the period 1964-1971 the shuttle if it already was, would have saved 2, 9% of the budget. Of course, these figures could not protect the shuttle, and NASA embarked on a slippery slope with the numbers game, "if it had been built space station, and if she needed a supply mission every two weeks, then it would have saved shuttles billion dollars a year." Also promoted the idea of ​​"starting with features such payloads will be cheaper, and there will be more than it is now, what else would increase savings." Only the combination of ideas "shuttle will fly often and save money on every start-up" and "new satellites for the space shuttle will be cheaper for existing disposable rockets" could make the shuttle cost-effective.


Economic calculations. Note that if you remove the "new moons" (bottom third of the table), the shuttles are uneconomical. I>


Economic calculations. Pay more now (left) and win in the future (right shaded area). I>

Parallel were complex political games involving firms potential producers, the Air Force, the government and NASA. For example, NASA lost the office of management and budget of the Executive Office of the President of the United States battle for the first-stage boosters. NASA wanted accelerators expander, but due to the fact that SRBs accelerators were cheaper development were selected last. Air Force, which sought military manned space programs with the X-20 and MOL, actually received military shuttle mission in exchange for political support for NASA. Production shuttles deliberately smeared across the country between different companies for the economic and political effect.
As a result of these complicated maneuvers, the contract for the development of the "Space Shuttle" was signed in the summer of 1972. The history of the production and operation beyond the scope of this article.

What do you get? H4>
Now, when the program is finished, it is possible with sufficient accuracy to tell what goals have been achieved, and what - no.

Achieved goals

Delivery of goods of different types (satellites, boosters, segment of the ISS). Ability to repair satellites in low Earth orbit. Ability to return to Earth satellites. Ability to send a flight of up to eight people. Implemented reusable. implemented a new layout of the spacecraft. Ability to horizontal maneuver. Large cargo bay. The cost and development time to meet the deadline promised by President Nixon in 1971.
not achieve their goal and dips
Quality facilitating access to space. Instead of reducing the price per kilogram of two orders of magnitude, "Space Shuttle" has become one of the most expensive means of delivering satellites into orbit. Fast preparation shuttles between flights. Instead of the expected period of two weeks between the flight shuttles ready to launch for months. Before the disaster "Challenger" record was 54 between the flights of the day, after the "Challenger" - 88 days. In all the years of operation of shuttles are launched an average of 4, 5 times a year instead of the minimum allowable by calculations of 28 times a year. Easy maintenance. Selected technical solutions have been very time-consuming to maintain. Main engines require removal and a lot of time on the service. Engine turbopump assembly of the first model required a full bulkhead and repair after each flight. Thermal protection tiles were unique - in each slot was set their own tiles. Total of 35 000 tiles, moreover, they can be lost or damaged in flight. Replace all disposable carrier. Shuttles never launched into polar orbit that is necessary for reconnaissance satellites. Were preparatory work, but they were stopped after the disaster "Challenger». A reliable access to space. Four orbiter meant that the space shuttle disaster - a loss of a quarter of the fleet. After a disaster, flights stopped for years. Also, the shuttles were notorious for constantly postponed starts. Load shuttle was five tons below the required specifications (24, 4 instead of 30) Large horizontal maneuver opportunities have never been used in reality from -this fact that the shuttle did not fly into a polar orbit. Return satellites orbit stopped in 1996. From orbit was returned all five satellites. Repair satellites, too, was weak demand. Total has been renovated five satellites (though Hubble served five times). Accepted engineering solutions adversely affect the reliability of the system. During takeoff and landing areas have been no chance of rescue of the crew in an emergency. Because of this death "Challenger". Mission STS-9 nearly ended in catastrophe because of a fire in the rear, which appeared already on the runway. Had this fire a minute earlier, the shuttle would have fallen without the chance of rescue of the crew. The fact that the shuttle is always flown manned at risk people without the need - for routine satellite launch lacked automation. Because of the low intensity of use shuttles morally outdated sooner than physically. In 2011, "Space Shuttle" was a very rare example of operation of the processor 80386 Disposable carriers could gradually upgrade the new series. Closing the program "Space Shuttle" superimposed on the abolition of the "Constellation", which led to a loss of self access to space for many years, image losses and need to buy a place in spaceships other countries. The new control system and nadkalibernye fairings allowed to run at large satellites disposable rockets. The shuttle holds a sad antirecord among space systems by the number of people killed.
 The "Space Shuttle" gave the United States a unique opportunity to work in space, but in terms of difference "that would - that got" we must conclude that it has not achieved its goals.

Why did it happen? H5>
Especially emphasize that at this point I express their views, perhaps some of them are wrong.

Shuttles were the result of many compromises between the interests of a few large organizations. Perhaps if there was one person or a team of associates who have had a clear vision of the system, it could take successful. The requirement to be "all things to all" and replace all the disposable rockets increased the cost and complexity of the system. Versatility by combining disparate requirements leads to a complication, more expensive, unnecessary functionality and efficiency worse than specialization. Easily add an alarm clock in a mobile phone - the speaker, watches, keys and electronic components already exist. But flying submarine will be more difficult and more expensive worse specialized aircraft and submarines. The complexity and cost of the system grows exponentially with the size. Perhaps shuttle 5-10 tons of payload (3-4 times less implemented) would be more successful. They could build more of the fleet make unmanned, make a one-time module for increasing the capacity of the heavier rare missions. «Dizzy with success". Successful implementation of the three programs consistently increasing complexity could turn the head of engineers and managers. In fact, that first manned launch unmanned without working out that the lack of systems for crew rescue ascent / descent talking about some self-confidence.

Hey, "Buran»? H5>
Anticipating the inevitable comparisons have little say about him. According to the "Buran" no statistics operation for many years. With it turned out something simpler - it covered rubble collapse of the USSR, and we can not say this program would be successful. The first part of this program - to "do as the Americans have" completed and that it would be more - is unknown.
And willing to arrange in the comments holivar "Which is better?" I ask beforehand to define what you think is "better". Because both the phrase "Buran has a large stock of characteristic velocity (delta-V), than the Space Shuttle" and "Space Shuttle does not reset expensive boosters with stage rocket" true.

List of sources (not including Wikipedia):

Ray A. Williamson TA Heppenheimer (wiki for some reason kicked out of a good table) , who repaired and returned shuttles. For pictures thanks to a group of VC.

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