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Honolulu HI (SPX) Aug 11, 2006 There seems to be general agreement that the Vision for Space Exploration is in deep trouble. Recently both the staid number-crunchers at Government Accountability Office (GAO)and the wild-eyed libertarians at the Space Frontier Foundation have issued reports questioning the viability of the program. The GAO analysis is concerned with management and contracting issues, and the SFF screed merely demands bigger government subsidies for the alt.space industry. My report will concentrate on what is really killing the program: the Ares I booster, formerly the Crew Launch Vehicle and vulgarly known as The Stick. The Stick began as a back-of-the-envelope design by some NASA astronauts who were angry about the Columbia crash and frankly terrified at the prospect of continuing to fly on the fundamentally defective Space Shuttle. They needed a design which could be quickly designed and put into service before the Shuttle killed another crew. This implied that the new booster should use existing Shuttle components to avoid a long development and qualification program. The Shuttle-derived concept also was essential to gain political support from the existing Shuttle contractors and their representatives in Congress. Given these constraints, it was inevitable that The Stick would end up as a single SSME stuck on top of a single SRB. It is important to remember that this design predates the VSE and was not intended for Moon or Mars missions. At this time it was assumed that NASA would continue to be focused on ISS for the foreseeable future. The Stick was only intended to replace the Shuttle for ISS crew exchange missions. For a long while The Stick had only an unofficial existence on the fringes of the space community. The first study was actually done by the Planetary Society, an organization advocating unmanned missions which has never before taken any interest in the troubles of the manned program. But when the shadowy authors of the VSE plan placed a hard limit of 2010 on Shuttle operations and 2016 on US participation in the ISS, The Stick suddenly became the only lifeline for the standing army of contractor employees and civil servants employed in the STS program. The SRB contractor ATK staged the most extensive publicity campaign in the history of the US aerospace industry, promoting The Stick with giant centerfold ads that proclaimed it as "Safe, Simple, and Soon". Then a major advocate of The Stick was appointed NASA Administrator. Mike Griffin insured that it became a major element of the return-to-the-Moon program - not only as an ISS ferry rocket, but as an element of the "1.5-launch" lunar landing plan. I and many critics have argued for some time that this plan would turn out to be far too complicated and expensive once real engineers started working out the technical details. And this is exactly what has happened. The second stage's air-start SSME engine turned out to be unworkable and had to be replaced with an Apollo-derived "J-2X" engine. This new second stage didn't have enough puff to reach orbit without the help of a new 5-segment SRB. This new SRB-5B is totally different from the current SRB-4 or even the old SRB-5A that was partly developed for the now-cancelled Shuttle upgrade program. Shuttle SRBs carry their loads divided between two side attachments instead of concentrated on the top dome. They also don't have to steer themselves through wind shears with a huge low-density hydrogen tank on top acting as a sail. The current Ares I has essentially no commonality with the Space Shuttle and will therefore take longer than The Original Stick to be developed and thoroughly tested. Current plans call for launching the first manned Ares-Orion test mission in late 2014. Regular missions to the ISS probably won't start until 2015 - and with normal schedule slippage, not until after US participation in ISS is supposed to end in 2016. One of the major justifications for The Stick was that it would give the thousands of workers who refurbish SRBs something to do in the gap between Shuttle and Ares V (CaLV). Clearly the delays introduced by dropping most Shuttle heritage will introduce another gap in SRB operations in 2010-2014. To close this employment gap, the planners of Project Orion have come up with a ridiculous "test" program in which the first few launches of Ares I will use first stages cobbled together from 4-segment Shuttle SRBs and dummy 5th segments. These proposed tests can't make any meaningful engineering contribution to the program. The flight dynamics of this Frankenbooster would be totally different from the operational vehicle due to its ~20% lower thrust. These launches have been inserted into the program only as an excuse to funnel about $400M/yr to Utah to maintain the SRB refurbishment facilities. So The Stick has turned out to have none of the properties attributed to it by its promoters. Instead of being simple, it is extremely complicated. Instead of being soon, it is late - so late that it cannot make a meaningful contribution to supporting the ISS. And the safety numbers assigned to it by NASA are sheer fantasy. More importantly, Ares I no longer accomplishes the political goals of maintaining steady employment at ATK and keeping Utah's congressmen in line. Instead, it has become a millstone around the neck of the entire VSE program. Even if Ares I were to be developed, it would lead to the ridiculous situation where the manned side of NASA would be operating two distinct booster designs, each of which would fly only twice per year. This is a recipe for super-high operations costs (rumored to exceed $5B per lunar landing). At the same time, the various US unmanned space programs will be using two more distinct booster families with low flight rates, each of which essentially duplicates the performance of Ares I. Mike Griffin needs to admit he was wrong about The Stick and pull the plug on it before any more time and money is wasted. He should replace Ares I with either the Delta-4 or Atlas-5. Better yet, he could scrap the 1.5-launch lunar mission plan and go back to Von Braun's original EOR concept with two Saturn-IV class HLVs. Both these options might require a significant reduction in the weight of the Orion (CEV) spacecraft by changes I will discuss in a future column. This might be a painful exercise, but it can't possibly be worse than pressing on with The Stick. Jeffrey F. Bell is a former space scientist and recovering pro-space activist.
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