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Pigeons were trained on a multiple variable-interval 30-sec, variable interval 90-sec schedule with each component presented alternately for an equal duration. This duration of exposure was varied from 5 to 300 sec. The rate of response in the variable-interval 30-sec component relative to the rate of response in the variable-interval 90-sec component was studied. Results are plotted and discussed.
The LRC MASS was modified and updated to include logic for efficient analysis of space shuttle payload operations. All MASS computer models were reviewed for compatibility with, and applicability to, the shuttle sortie mission. The MASS modification efforts were concentrated on two computer programs, the general scheduling model (GSM) and one day model (ODM). A new computer program, the DAYLIB Tape Processor, was developed to update the link between the GSM and ODM. The resulting MASS is an operationally efficient analytical tool that will allow a rapid assessment of shuttle and shuttle payload operations.
The problem of determining the cost impact attributable to perturbations in an aerospace R and D program schedule is discussed in terms of the diminishing availability of funds. The methodology from which a model is presented for updating R and D cost estimates as a function of perturbations in program time is presented.
A computer system is reported that effectively schedules complex mission support by processing spacecraft requirements, station capabilities, and ephemeris data in teletype format ready for transmission.
The factors involved in scheduling airline services for international operations are discussed. Charts are presented to show the transatlantic pattern of flights for a typical airline during the summer and winter months. The operations of a domestic airline operating overseas and a foreign airline operating to the United States are compared.
The supporting cost and schedule data for the second half of the Space Shuttle System Phase B Extension Study is summarized. The major objective for this period was to address the cost/schedule differences affecting final selection of the HO orbiter space shuttle system. The contending options under study included the following booster launch configurations: (1) series burn ballistic recoverable booster (BRB), (2) parallel burn ballistic recoverable booster (BRB), (3) series burn solid rocket motors (SRM's), and (4) parallel burn solid rocket motors (SRM's). The implications of varying payload bay sizes for the orbiter, engine type for the ballistics recoverable booster, and SRM motors for the solid booster were examined.
A high level computer programming language and a program library were developed to be used in writing programs for scheduling complex systems such as the space transportation system. The objectives and requirements of the study are summarized and unique features of the specified language and program library are described and related to the why of the objectives and requirements.
The scheduling of space shuttle missions within specified window and resource constraints are reported. Models are described for selecting qualified resource units to the mission assignments.
The approach and organization of the study to develop a high level computer programming language and a program library are presented. The algorithm and problem modeling analyses are summarized. The approach used to identify and specify the capabilities required in the basic language is described. Results of the analyses used to define specifications for the scheduling module library are presented.
This study presents Tug Fleet and Ground Operations Schedules and Controls plan. This plan was developed and optimized out of a combination of individual Tug program phased subplans, special emphasis studies, contingency analyses and sensitivity analyses. The subplans cover the Tug program phases: (1) Tug operational, (2) Interim Upper Stage (IUS)/Tug fleet utilization, (3) and IUS/Tug payload integration, (4) Tug site activation, (5) IUS/Tug transition, (6) Tug acquisition. Resource requirements (facility, GSE, TSE, software, manpower, logistics) are provided in each subplan, as are appropriate Tug processing flows, active and total IUS and Tug fleet requirements, fleet management and Tug payload integration concepts, facility selection recommendations, site activation and IUS to Tug transition requirements. The impact of operational concepts on Tug acquisition is assessed and the impact of operating Tugs out of KSC and WTR is analyzed and presented showing WTR as a delta. Finally, cost estimates for fleet management and ground operations of the DDT&E and operational phases of the Tug program are given.
The results of a study to assess the tug safing requirements at postlanding are presented. The study considered the normal (green light) conditions from orbiter landing to completion of preparations for the next launch. Normal tug ground turnaround operations include handling and transportation activities and the performance of inspections, tests, and checkout functions. These activities dictate that hazards to ground personnel, the tug, GSE, facilities, and ecology be reduced to the lowest practical level consistent with program objectives, cost, and schedules. During flight operations, the tug contains energy sources that constitute potential hazards but are required for mission accomplishment. These potential hazards have been reduced to an acceptable level for flight operation by design features and by providing for control of energy sources.
A user guide for the Programming Language for Allocation and Network Scheduling (PLANS) is presented. Information is included for the construction of PLANS programs. The basic philosophy of PLANS is discussed, and access and update reference techniques are described along with the use of tree structures.
The financial history of the U.S. scheduled airline industry was investigated to determine the causes of the erratic profit performance of the industry and to evaluate potential economic gains from technology advances of recent years. Operational and economic factors affecting past and future profitability of the industry are discussed, although no attempt was made to examine the profitability of individual carriers. The results of the study indicate that the profit erosion of the late 1960's and early 1970's was due more to excess capacity than to inadequate fare levels, but airline problems were severely compounded by the rapid fuel price escalation in 1974 and 1975. Near-term solutions to the airline financial problems depend upon the course of action by the industry and the CAB and the general economic health of the nation. For the longer term, the only acceptable alternative to continued fare increases is a reduction in unit operating costs through technological advance. The next generation of transports is expected to incorporate technologies developed under Government sponsorship in the 1960's and 1970's with significant improvements in fuel consumption and operating costs.
A computer program using Lemke, Salkin and Spielberg's Set Covering Algorithm (SCA) to optimize a traffic model problem in the Scheduling Algorithm for Mission Planning and Logistics Evaluation (SAMPLE) was documented. SCA forms a submodule of SAMPLE and provides for input and output, subroutines, and an interactive feature for performing the optimization and arranging the results in a readily understandable form for output.
A progress report is given on various systems, noting conformity to schedule or changes in design. The Orbiter thermal protection system, the Space Shuttle main engine, the intertank for the structural test article (STA), thrust vector control systems, the Kennedy Space Center launch processing system, and Orbiters No. 1 and No. 2 are discussed.
The operation and the expected performance of a proposed automatic guideway transit system which uses low speed automated mixed traffic vehicles (AMTVs) were analyzed. Vehicle scheduling and headway control policies were evaluated with a transit system simulation model. The effect of mixed traffic interference on the average vehicle speed was examined with a vehicle pedestrian interface model. Control parameters regulating vehicle speed were evaluated for safe stopping and passenger comfort. Some preliminary data on the cost and operation of an experimental AMTV system are included. These data were the result of a separate task conducted at JPL, and were included as background information.
The HEAO-A observatory, scheduled for launch in late June 1977, will spend most of its orbital lifetime in a scanning mode, spining from 0.03 to 0.1 rpm about an axis aligned with the sun. The dates of availability in the scan band are given for a list of 248 X-ray sources. Celestial maps of source locations and scan planes, and examples of the nighttime elevation of available sources are presented. This document is intended to aid ground-based observers in planning coordinated observations with HEAO-A.
Cost estimates for the space station systems analysis were recorded. Space construction base costs and characteristics were cited as well as mission hardware costs and characteristics. Also delineated were cost ground rules, the program schedule, and a detail cost estimate and funding distribution.