Author :
Garcia-Galan, Carlos ; Armstrong, Robert E. ; Lammers, Michael L. ; McMillan, Courtenay R.
Abstract :
Over the last four decades of human spaceflight, the capabilities and complexity of manned spacecraft systems have increased significantly to meet the evolving requirements of the mission. The management of the vehicle systems, both by the crew on-board and the operators in the mission control center (MCC), has also evolved to take advantage of new capabilities, or simply to react to the features of the spacecraft design. As we embark in a new era of space exploration, with firm plans for the development of a new fleet of spacecraft intended to carry out the objectives of the Constellation program, it is relevant to examine important lessons learned on the design and management of manned spacecraft systems and the mission. This paper will focus on lessons learned related to system management capabilities that directly impact crew safety, mission success and/or improve operability of the spacecraft. In particular, the authors will examine current system design features, capabilities and processes that provide valuable capabilities or create operational challenges for the current manned spacecraft operated by NASA; the space transportation system (STS) (a.k.a. the space shuttle) and the International Space Station (ISS). Furthermore, it is important to analyze relevant events for which specific design capabilities have enabled safety or mission success, and others where system or process anomalies led to reduced system capabilities or operational challenges. A notable example of such events are the recent on-board command and control (C&C) computer anomalies in ISS, both on the US (during mission ISS 6A) and Russian segments (mission ISS 13A). For such events, it is important to understand the root-cause of the problem, to avoid it in future designs. However, it is more relevant to understand what aspects of the design led to the mitigation or further propagation of the impact of the failure, and the capabilities that enabled the team to recover from the anomalie- s. Moreover, relevant lessons learned are equally beneficial to standard practices or specific system capabilities that provide enabling tools for safer and more efficient operations. The purpose of this paper is to identify relevant operational lessons learned from current architectural designs and processes. For that purpose, the authors combine the discussion of "real-life" events, along with selected standard desired design features, to provide an illustration of capabilities that should be considered during the design and implementation of future spacecraft, including the crew exploration vehicle (CEV) and other elements of the Constellation program.
Keywords :
space vehicles; Constellation program; International Space Station; crew exploration vehicle; human spaceflight; manned spacecraft systems; mission control center; onboard command-and-control computer anomalies; operational lessons; space shuttle; space transportation system; systems management; Automatic control; Automation; Control systems; Humans; NASA; Safety; Space exploration; Space shuttles; Space stations; Space vehicles;