Friday, July 19, 2019
space :: essays research papers
People arguing over shuttle costs on the net are usually arguing from different assumptions and do not describe their assumptions clearly, making it impossible to reach agreement. To demonstrate the difficulty, here are a range of flight cost figures differing by a factor of 35 and some of the assumptions behind them (all use 1992 constant dollars). $45 million - marginal cost of adding or removing one flight from the manifest in a given year. $414 million - NASA's average cost/flight, assuming planned flight rates are met and using current fiscal year data only. $1 billion - operational costs since 1983 spread over the actual number of flights. $900 million - $1.35 billion - total (including development) costs since the inception of the shuttle program, assuming 4 or 8 flights/year and operations ending in 2005 or 2010. $1.6 billion - total costs through 1992 spread over the actual number of flights through 1992. For more detailed information, see the Aviation Week Forum article by Roger A. Pielke, Jr.: "Space Shuttle Value Open To Interpretation", July 26, 1993, pg. 57. WHAT HAPPENED TO THE SATURN V PLANS Despite a widespread belief to the contrary, the Saturn V blueprints have not been lost. They are kept at Marshall Space Flight Center on microfilm. The Federal Archives in East Point, GA also has 2900 cubic feet of Saturn documents. Rocketdyne has in its archives dozens of volumes from its Knowledge Retention Program. This effort was initiated in the late '60s to document every facet of F-1 and J-2 engine production to assist in any future re-start. The problem in re-creating the Saturn V is not finding the drawings, it is finding vendors who can supply mid-1960's vintage hardware (like guidance system components), and the fact that the launch pads and VAB have been converted to Space Shuttle use, so you have no place to launch from. By the time you redesign to accommodate available hardware and re-modify the launch pads, you may as well have started from scratch with a clean sheet design. Other references: Several AIAA papers delivered in recent years discuss reviving the Saturn V. For example, AIAA paper 92-1546, "Launch Vehicles for the Space Exploration Initiative". This paper concluded that a revived Saturn V was actually cheaper than the NLS vehicle. An overview of the infrastructure still available to support production of a 1990s Saturn V and how that vehicle might be used to support First Lunar Outpost missions can be found in the December 1993 issue of _Spaceflight_, published by the British Interplanetary Society. WHY DATA FROM SPACE MISSIONS ISN'T IMMEDIATELY AVAILABLE
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