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Phased Project Planning Guidelines

NHB 7121.2 is the initial publication of the guidelines for implementation of the Phased Project Planning (PPP) concept prescribed by NPD 7121,1A. These guidelines are applicable to the planning and approval activities which lead to the implementation of major new research and development projects as defined in NPD 7121.1A as well as to major modifications or extensions of approved projects. They should, therefore, be reflected in the Project Approval Documents which serve as the basic documentation for project definition, guidance and control throughout NASA. The purpose of PPP is to provide, through defined phases, an adequate basis for management decisions on the extent to which project activities can be properly undertaken and commitments made. However, these guidelines do not prescribe detailed format and content of plans and other documents and reports used to apply the PPP concept. Similarly, the work content of phases and the information requirements described herein are not checklists. They are included to assist in understanding the intent of the PPP concept and should not be viewed as rigid or inflexible. PPP, as a concept for orderly planning and definition of new major R&D undertakings, must be adapted to the peculiarities of each individual case. However, the flexibility permitted for adaptation should not be considered as a license for major variation which would compromise the objectives that underlie the concept. Cognizant NASA officials are expected to pursue their project planning and definition activities in reasonable conformance with these guidelines and to request only those exceptions or deviations which are clearly necessary and justified. These guidelines will be modified as determined necessary on the basis of experience. Comments or suggestions for changes should be directed to the Office of Organization and Management.

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Logistics planning for phased programs.

It is pointed out that the proper and early integration of logistics planning into the phased program planning process will drastically reduce these logistics costs. Phased project planning is a phased approach to the planning, approval, and conduct of major research and development activity. A progressive build-up of knowledge of all aspects of the program is provided. Elements of logistics are discussed together with aspects of integrated logistics support, logistics program planning, and logistics activities for phased programs. Continuing logistics support can only be assured if there is a comprehensive sequential listing of all logistics activities tied to the program schedule and a real-time inventory of assets.

Cook, W. H.↗

Vehicle management and mission planning in support of shuttle operations.

An operational approach to shuttle mission planning during high flight frequency years (20 or more flights per year) is described wherein diverse mission planning functions interface via an interactive computer system and common data base. The Vehicle Management and Mission Planning System (VMMPS) is proposed as a means of helping to accomplish the mission planning function. The VMMPS will link together into an interactive system the major mission planning areas such as trajectory, crew, vehicle performance, and launch operations. A common data base will be an integral part of the system and the concept of standard mission types and phases will be used to minimize mission to mission uniqueness. The use of this system will eliminate much redundancy and replanning, shorten interface times between functions, and provide a means to evaluate unplanned events and modify schedules.

Pruett, W. R.↗

Systems design study of the Pioneer Venus spacecraft. Volume 2. Preliminary program development plan

The preliminary development plan for the Pioneer Venus program is presented. This preliminary plan treats only developmental aspects that would have a significant effect on program cost. These significant development areas were: master program schedule planning; test planning - both unit and system testing for probes/orbiter/ probe bus; ground support equipment; performance assurance; and science integration Various test planning options and test method techniques were evaluated in terms of achieving a low-cost program without degrading mission performance or system reliability. The approaches studied and the methodology of the selected approach are defined.

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Experiment planning during the Skylab missions

The objectives of the Skylab Program included observations of the earth, the sun, the stars, and a comet in addition to a variety of engineering and medical experiments. Attention is given to mission planning activities accomplished before the launch of the orbital workshop, during the manned missions, and between manned missions. Two major purposes of early experiments planning were related to the establishment of reasonable potential goals in terms of accomplishment and the discovery of potential problems in scheduling. Planning during the mission proceeded according to a scheme in which the planning was done on a daily basis. Experiences from the three Skylab missions are discussed separately. The results of the Skylab Program demonstrate the value of the daily experiment planning system that was capable of reacting to changing constraints.

Sevier, J. R.↗

Advanced space system concepts and their orbital support needs (1980 - 2000). Volume 4: Detailed data. Part 2: Program plans and common support needs (a study of the commonality of space vehicle applications to future national needs

The methodology of alternate world future scenarios is utilized for selecting a plausible, though not advocated, set of future scenarios each of which results in a program plan appropriate for the respective environment. Each such program plan gives rise to different building block and technology requirements, which are analyzed for common need between the NASA and the DoD for each of the alternate world scenarios. An essentially invariant set of system, building block, and technology development plans is presented at the conclusion, intended to allow protection of most of the options for system concepts regardless of what the actual future world environment turns out to be. Thus, building block and technology needs are derived which support: (1) each specific world scenario; (2) all the world scenarios identified in this study; or (3) generalized scenarios applicable to almost any future environment. The output included in this volume consists of the building blocks, i.e.: transportation vehicles, orbital support vehicles, and orbital support facilities; the technology required to support the program plans; identification of their features which could support the DoD and NASA in common; and a complete discussion of the planning methodology.

Bekey, I.↗

Formulation of detailed consumables management models for the development (preoperational) period of advanced space transportation system. Volume 1: Detailed requirements for the mission planning processor

Detailed requirements for the mission planning processor are documented. The mission planning processor is a user oriented tool for consumables management and is part of the total consumables subsystem management concept. A quasi top-down approach was applied to the design of the mission planning processor. Interface requirements, input/output, and data base concepts were considered before computational processing. Existing analytical models were investigated for applicability before new models were developed. The mission planning processor was designed for an interactive system using demand terminals for input/outputdisplay and interfacing with an updateable mission data bank. The control and support routines provide the user interface, peripheral data handling, program control, and support functions required by the mission planning processor for execution on an interactive system. A description, interface requirements, definition of internal variables, listing of input data, processing flow diagram, and listing of output data are presented for each routine.

Connelly, L. C.↗

Two-stage chain sampling inspection plans with different sample sizes in the two stages

A further generalization of the family of 'two-stage' chain sampling inspection plans is developed - viz, the use of different sample sizes in the two stages. Evaluation of the operating characteristics is accomplished by the Markov chain approach of the earlier work, modified to account for the different sample sizes. Markov chains for a number of plans are illustrated and several algebraic solutions are developed. Since these plans involve a variable amount of sampling, an evaluation of the average sampling number (ASN) is developed. A number of OC curves and ASN curves are presented. Some comparisons with plans having only one sample size are presented and indicate that improved discrimination is achieved by the two-sample-size plans.

Stephens, K. S.↗

Shuttle payload vibroacoustic test plan evaluation

Statistical decision theory is used to evaluate seven alternate vibro-acoustic test plans for Space Shuttle payloads; test plans include component, subassembly and payload testing and combinations of component and assembly testing. The optimum test levels and the expected cost are determined for each test plan. By including all of the direct cost associated with each test plan and the probabilistic costs due to ground test and flight failures, the test plans which minimize project cost are determined. The lowest cost approach eliminates component testing and maintains flight vibration reliability by performing subassembly tests at a relatively high acoustic level.

Stahle, C. V.↗

The influence of various test plans on mission reliability

Methods have been developed for the evaluation of cost effective vibroacoustic test plans for Shuttle Spacelab payloads. The shock and vibration environments of components have been statistically represented, and statistical decision theory has been used to evaluate the cost effectiveness of five basic test plans with structural test options for two of the plans. Component, subassembly, and payload testing have been performed for each plan along with calculations of optimum test levels and expected costs. The tests have been ranked according to both minimizing expected project costs and vibroacoustic reliability. It was found that optimum costs may vary up to $6 million with the lowest plan eliminating component testing and maintaining flight vibration reliability via subassembly tests at high acoustic levels.

Stahle, C. V.↗

Studies of planning behavior of aircraft pilots in normal, abnormal and emergency situations

A methodology for the study of planning is presented and the results of applying the methodology within two experimental investigations of planning behavior of aircraft pilots in normal, abnormal, and emergency situations are discussed. Beyond showing that the methodology yields consistent results, these experiments also lead to concepts in terms of a dichotomy between event driven and time driven planning, subtle effects of automation on planning, and the relationship of planning to workload and flight performance.

Johannsen, G.↗

Planning satellite communication services and spectrum-orbit utilization

The relationship between approaches to planning satellite communication services and spectrum-orbit utilization is considered, with emphasis on the fixed-satellite and the broadcasting-satellite services. It is noted that there are several possible approaches to planning space services, differing principally in the rigidity with which technical parameters are prescribed, in the time for which a plan remains in force, and in the procedures adopted for implementation and modifications. With some planning approaches, spectrum-orbit utilization is fixed at the time the plan is made. Others provide for greater flexibility by making it possible to postpone some decisions on technical parameters. In addition, the two political questions of what is equitable access and how it can be guaranteed in practice play an important role.

Sawitz, P. H.↗

NASA deep space network operations planning and preparation

The responsibilities and structural organization of the Operations Planning Group of NASA Deep Space Network (DSN) Operations are outlined. The Operations Planning group establishes an early interface with a user's planning organization to educate the user on DSN capabilities and limitations for deep space tracking support. A team of one or two individuals works through all phases of the spacecraft launch and also provides planning and preparation for specific events such as planetary encounters. Coordinating interface is also provided for nonflight projects such as radio astronomy and VLBI experiments. The group is divided into a Long Range Support Planning element and a Near Term Operations Coordination element.

Jensen, W. N.↗

Comparative analysis of operational forecasts versus actual weather conditions in airline flight planning, volume 2

The impact of more timely and accurate weather data on airline flight planning with the emphasis on fuel savings is studied. This volume of the report discusses the results of Task 2 of the four major tasks included in the study. Task 2 compares various catagories of flight plans and flight tracking data produced by a simulation system developed for the Federal Aviation Administrations by SRI International. (Flight tracking data simulate actual flight tracks of all aircraft operating at a given time and provide for rerouting of flights as necessary to resolve traffic conflicts.) The comparisons of flight plans on the forecast to flight plans on the verifying analysis confirm Task 1 findings that wind speeds are generally underestimated. Comparisons involving flight tracking data indicate that actual fuel burn is always higher than planned, in either direction, and even when the same weather data set is used. Since the flight tracking model output results in more diversions than is known to be the case, it was concluded that there is an error in the flight tracking algorithm.

Keitz, J. F.↗

Comparative analysis of operational forecasts versus actual weather conditions in airline flight planning: Summary report

The impact of more timely and accurate weather data on airline flight planning with the emphasis on fuel savings is studied. This summary report discusses the results of each of the four major tasks of the study. Task 1 compared airline flight plans based on operational forecasts to plans based on the verifying analyses and found that average fuel savings of 1.2 to 2.5 percent are possible with improved forecasts. Task 2 consisted of similar comparisons but used a model developed for the FAA by SRI International that simulated the impact of ATc diversions on the flight plans. While parts of Task 2 confirm the Task I findings, inconsistency with other data and the known impact of ATC suggests that other Task 2 findings are the result of errors in the model. Task 3 compares segment weather data from operational flight plans with the weather actually observed by the aircraft and finds the average error could result in fuel burn penalties (or savings) of up to 3.6 percent for the average 8747 flight. In Task 4 an in-depth analysis of the weather forecast for the 33 days included in the study finds that significant errors exist on 15 days. Wind speeds in the area of maximum winds are underestimated by 20 to 50 kts., a finding confirmed in the other three tasks.

Keitz, J. F.↗

Space station human productivity study. Volume 5: Management plans

The 67 Management Plans represent recommended study approaches for resolving 108 of the 305 Issues which were identified. Each study Management Plan is prepared in three formats: Management Plan Overview (lists the subsumed Issues, study background, and related overview information); Study Plan (details the study approach by tasks, lists special needs, and describes expected study products); Schedule-Task Flow (provides a time-lined schedule for the study tasks and resource requirements). The Management Relationships Matrix, included in this volume, shows the data input-output relationships among all recommended studies. A listing is also included which cross-references the unresolved requirements to Issues to management plans. A glossary of all abbreviations utilized is provided.

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Search Problems in Mission Planning and Navigation of Autonomous Aircraft

An architecture for the control of an autonomous aircraft is presented. The architecture is a hierarchical system representing an anthropomorphic breakdown of the control problem into planner, navigator, and pilot systems. The planner system determines high level global plans from overall mission objectives. This abstract mission planning is investigated by focusing on the Traveling Salesman Problem with variations on local and global constraints. Tree search techniques are applied including the breadth first, depth first, and best first algorithms. The minimum-column and row entries for the Traveling Salesman Problem cost matrix provides a powerful heuristic to guide these search techniques. Mission planning subgoals are directed from the planner to the navigator for planning routes in mountainous terrain with threats. Terrain/threat information is abstracted into a graph of possible paths for which graph searches are performed. It is shown that paths can be well represented by a search graph based on the Voronoi diagram of points representing the vertices of mountain boundaries. A comparison of Dijkstra's dynamic programming algorithm and the A* graph search algorithm from artificial intelligence/operations research is performed for several navigation path planning examples. These examples illustrate paths that minimize a combination of distance and exposure to threats. Finally, the pilot system synthesizes the flight trajectory by creating the control commands to fly the aircraft.

Krozel, James A.↗

PLAN-IT - Knowledge-based mission sequencing

PLAN-IT (Plan-Integrated Timelines), a knowledge-based approach to assist in mission sequencing, is discussed. PLAN-IT uses a large set of scheduling techniques known as strategies to develop and maintain a mission sequence. The approach implemented by PLAN-IT and the current applications of PLAN-IT for sequencing at NASA are reported.

Biefeld, Eric W.↗