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Title: Letter to Congress - NASA
Source:
nasaproblems
URL Source: http://www.nasaproblems.com/
Published: Jul 4, 2006
Author: Don A. Nelson
Post Date: 2006-07-04 13:32:21 by TLBSHOW
Keywords: None
Views: 176
Comments: 1
Letter to Congress April 17 2006 The Honorable Senator Kay Bailey Hutchinson 2246 Rayburn House Office Building Washington, DC 20515-3223 Dear Senator: As a retired NASA aerospace engineer, I and a growing number of my colleagues are very concerned about the technical and management issues with the space shuttle replacement, the Crew Exploration Vehicle/Crew Launch Vehicle (CEV/CLV). Engineering analyses are revealing that this expendable space transportation concept derived from Apollo/space shuttle components will have exorbitant development and operations cost and serious flight safety issues. Please consider the following: * The structural and flight operation functions of this questionable configuration are in no way like those of their derived Apollo and shuttle sources. Significant and costly modifications will be required. * The flight control capability of the first stage is dubious. A lack of flight control authority margin and the prevailing launch winds could cause the loss of the vehicle. * Launch performance shortfalls caused by errors in weight estimations are now requiring a first stage solid rocket motor with five instead of the current four segments. This configuration has never been flight tested and complicates the existing flight control problem. It also increases the probability of a Challenger type seal failure because of higher flex loads at the joints. * More weight penalty is required to prevent the CEV service module reentry debris from falling into populated areas. * NASA had stated that the CEV/CLV would be so safe that it would have only one catastrophic failure in 2000 flights. In fact the Apollo type parachute landing of this very heavy crew module puts the crew at extreme risk. The Russian space authorities are working to eliminate parachute landings on their next generation crewed spacecraft. * The CEV/CLV cannot carry some of the space station critical components like the control moment gyros. If one of these critical components fails, the station will be lost. * Because of the large manufacturing workforce needed for expendable space vehicles, the mission operations cost will exceed $700 million yearly. This budget impacting cost cannot be offset because the CEV/CLV has no commercial or military applications. Expendable space transportation systems have been rejected as unaffordable in two previously comprehensive studies; “Access to Space” and “First lunar Outpost”. Both of these studies revealed the need for a space vehicle technology program with goals to increase flight performance, safety, and reduce operations costs. Unfortunately this has not occurred. The failure of the Evolved Expendable Launch Vehicles to attract any significant commercial interest has again confirmed that an expendable space launch system with high labor cost is not possible without costly government supplements. NASA Administrator Michael Griffin’s call for a “60 days” study to revamp the CEV concept was a warning that NASA was not in a position to support the human transportation requirements for the Vision for Space exploration. Regrettably Administrator Griffin has chosen to proceed on a course that has already proven untenable and resulted in the cancellation of the Apollo program. It is the same course he chose for the failed First Lunar Outpost project. NASA is proceeding on this course unchallenged because there has been no independent evaluation of their “60 days” CEV/CLV. The Office of Inspector General has attempted to establish an engineering capability to evaluate space transportation concepts but failed. NASA and contractor employees who are aware of the shortcoming of the CEV/CLV are not coming forward. It is strongly recommended that the Government Accountability Office and the Congressional Budget Office be directed to evaluate cost and justification for proceeding with the CEV/CLV. NASA Administrator Griffin has described the process of retiring the space shuttle as a “speed bump.” It can more accurately be described as a “crevasse” being filled with NASA science programs for a launch concept which is already obsolete. Don A. Nelson Retired NASA Aerospace Engineer
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