Range Safety Officers (RSOs) are used by NASA and other government agencies to assure protection of life and property during launch operations. The current decision-making system used by the RSOs at NASA Wallops Flight Facility (WFF) and the National Ranges, including the Eastern Range (ER) and Western Range (WR), was conceptually developed in the late 1960's and early 1970's. From time to time, improvements have been implemented to increase reliability. However, technology did not exist to make significant improvements in the 3-to-5-second RSO decision-making time. Today, it appears technically feasible to make significant improvements to this system.

Since the 1970's, advances in technology have significantly increased the amount of real-time data, produced low-cost high-speed computer systems, added new data sources, and produced "smart" guidance systems for launch vehicles. Today's telemetry systems provide large quantities of real-time data, which can be readily evaluated by new computer systems. These computer systems now have the processing power and software to perform real-time analyses at low cost, within the decision-making constraints of range safety. Global Positioning Systems (GPSs) have also increased the amount of available decision-making data. Currently, many launch-vehicle systems use smart guidance processors, which compute a new trajectory to orbit once the vehicle has deviated from the pre-launch nominal trajectory. In spite of these advances, the current range safety system does not provide the RSO with the optimum tools to determine whether deviated paths are abnormal vehicle paths or solutions to unexpected conditions.

The Range Safety Smart System (RSSS) was conceived to advance the Range Safety System technology used to make destruct/no-destruct decisions during vehicle flight. The system will provide more accurate and timely advisories on multiple tasks or data inputs within the range safety time constraints of launch vehicle and ground-based systems. A system of processing, analyzing, certifying, and comparing the additional available data, and presenting it to the RSO in a manner which does not add to his/her monitoring burden, will greatly enhance the quality of the real-time destruct/no-destruct decisions; additionally, it will reduce the probability of destructing a good vehicle, increase mission success, and reduce operational cost by reducing the number of RSO support personnel.

In October 1990, Research Triangle Institute (RTI) proposed to utilize computer thought-processing to evaluate real-time RSO decision-making data and present it in a manner that could reduce the RSO's real-time workload and reduce the number of support personnel. In response to this proposal, NASA initiated the RSSS effort. To date, the following have been completed: (1) System Definition, (2) Proof-of-Concept, and (3) Development of a RSSS Demonstration Model. The first two phases were performed by RTI. Phase III, Development of a Demonstration Model, was performed jointly by NASA WFF and RTI.

The demonstration model has been shown to various groups at NASA and DoD. The ER utilized some of the concepts demonstrated in the demonstration model in the Cassini mission. This technology may be adopted by other operational groups at NASA, DoD, and the private sector, who could benefit from its data-acquiring, analyzing, and advising capabilities.

This work was done by Jaya Bajpayee of Goddard Space Flight Center. For inquiries on the RSSS, please contact Jaya Bajpayee at (301)286-0569.


NASA Tech Briefs Magazine

This article first appeared in the November, 2000 issue of NASA Tech Briefs Magazine.

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