Onboard versus ground checkout of fluid mechanical systems
Tradeoff of autonomous onboard checkout versus ground checkout of space shuttle fluid mechanical systems
Mavros, L. A.↗
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A study of a Jupiter atmospheric entry probe mission. Volume 1: Mangement summary
Science and engineering tradeoffs for Jupiter atmospheric entry probe mission
Winkler, H. B.↗
Memory reduction through higher level language hardware
Computer memory reduction through Fortran higher level language, discussing tradeoff between costs saved and additional logic hardware
Gellman, L.↗
The biosatellite fuel cell/battery power system
Biosatellite hydrogen oxygen fuel cell/silver zinc battery combination power system for long aerospace missions, discussing optimal design tradeoff
Bennett, C. W.↗
Survival of a Jovian atmospheric probe
Thermal control, pressure survival and structural tradeoffs of Jovian atmospheric probe for mission parametric studies
Schelden, B. G.↗
Error control for the SMS data collection system
Synchronous meteorological satellite data collection and transmission system error control, considering design tradeoffs for radio sets and coding techniques
Wiggert, D.↗
A study of a Jupiter atmospheric entry probe mission to the base of the cloud layers
Jupiter atmospheric entry probe missions to cloud layers base, discussing tradeoffs between various types of mission trajectories and technologies
Fields, D. P.↗
Reliability's role in key project decisions
Reliability in key project decision making, including failure mode/effect analyses, design tradeoff, baseline meetings, hardware storage and data bases
Cohen, H.↗
A look at control law influences on the rigid body bending moments for boost vehicles with various degrees of aerodynamic stability
Space shuttle boost vehicle with various degrees of aerodynamic stability, discussing control laws effects on rigid body bending moment tradeoff
Mowery, D. K.↗
A technique for lifting entry and terminal phase system optimization for the 1975 Mars Viking lander
Lifting entry and terminal phase system optimization for 1975 Mars Viking lander, considering graphical tradeoff approach including design parameter and atmosphere model variations
French, C. E.↗
Fluidic pressure regulators
Three basic areas for possible application of fluidic control to rocket engine subsystems were identified and six subsystem configurations were analyzed for study. Results provide indication of tradeoffs involved between conventional and fluidic regulators and should be of interest to control and applications engineers who need to make similar analyses.
Mangion, C.↗
TOPS attitude propulsion subsystem technology
The thermoelectric outer-planet spacecraft (TOPS) attitude propulsion subsystem effort is summarized. It includes the tradeoff rationale that went into the selection of anhydrous hydrazine as the propellant, and a brief description of three types of 0.445-N (100-mlbf) thrusters that were purchased for in-house evaluation. A discussion is also included of the 0.2224-N (50-mlbf)-developed thrusters and their integration with a portable, completely enclosed, propulsion module that was designed and developed to support the TOPS single-axis attitude control tests in the celestarium.
Moynihan, P. I.↗
Mars surface sample return missions via solar electric propulsion
The characteristics and capabilities are described of solar electric propulsion (SEP) for performing Mars Surface Sample Return (MSSR) missions. The scope of the study emphasizes trajectory/payload analysis and the comparison of mission/system tradeoff options. The MSSR mission is examined only for the 1981-82 launch opportunity. Several other study constraints which bear directly on the results obtained are: (1) return samples in the range 5-25 kg, (2) use of lifting (offset C.G.) atmospheric entry at Mars which allows a low ratio (1.25) of entry weight to landed weight, and (3) rendezvous and docking in Mars orbit. Major results of the study are presented as performance curves of earth departure mass versus sample size for a number of different mission/system options. These options represent a spectrum of trip time, launch vehicle capability, combinations of low-thrust and ballistic maneuvers, chemical retro type, and earth recovery mode.
Spadoni, D. J.↗
Aerospace vehicle separation mechanisms selection, design, and use considerations
The principal types of separation systems and mechanisms used in spacecraft are described and compared. Important parameters to be considered in tradeoff studies are discussed. Several examples of successful applications and failures and the lessons learned from them are discussed.
Gluckman, I. B.↗
A lightweight bimetallic actuator for spacecraft thermal control
The design, development, and construction of two types of active thermal-control systems are described. These designs are based on the controlled angular deflections of spiral-wound bimetallic actuators. The use of these actuators and lightweight louvers results in a frictionless system that is low in weight yet simple in design and low in cost. Both designs exhibit high reliability, good performance repeatability, and do not require power from the spacecraft. Design philosophy and implementation, design tradeoffs, and materials selection are reviewed. The test program is described, and results are presented.
Schilling, K. L.↗
Economic utilization of general aviation airport runways
The urban general aviation airport economics is studied in detail. The demand for airport services is discussed, and the different types of users are identified. The direct cost characteristics of the airport are summarized; costs to the airport owner are largely fixed, and, except at certain large airports, weight is not a significant factor in airport costs. The efficient use of an existing airport facility is explored, with the focus on the social cost of runway congestion as traffic density at the airport build up and queues form. The tradeoff between aircraft operating costs and airport costs is analyzed in terms of runway length. The transition from theory to practice is treated, and the policy of charging prices only on aircraft storage and fuel is felt likely to continue. Implications of the study from the standpoint of public policy include pricing that spreads traffic peaks to improve runway utilization, and pricing that discriminates against aircraft requiring long runways and causes owners to adopt V/STOL equipment.
Piper, R. R.↗
Fifteen-foot diameter modular space station Kennedy Space Center launch site support definition (space station program Phase B extension definition)
This document defines the facilities, equipment, and operational plans required to support the MSS Program at KSC. Included is an analysis of KSC operations, a definition of flow plans, facility utilization and modifications, test plans and concepts, activation, and tradeoff studies. Existing GSE and facilities that have a potential utilization are identified, and new items are defined where possible. The study concludes that the existing facilities are suitable for use in the space station program without major modification from the Saturn-Apollo configuration.
Bjorn, L. C.↗
Vertical resolution of temperature profiles obtained from remote radiation measurements
The Backus-Gilbert theory is applied to the problem of the vertical sounding of the atmosphere by means of remote radiation measurements. An application is made to spectral intervals 2.8/cm wide in the 667/cm band of CO2, and tradeoff curves are presented which quantitatively define the relationship between intrinsic vertical resolution and random error in temperature profile estimates. It is found that for a 1-2K random error with state-of-the-art instrumentation, the intrinsic vertical resolution ranges from approximately 0.5 local scale height (l.s.h.) in the lower troposphere to 2 l.s.h. in the upper stratosphere with approximately 2 l.s.h. resolution in the vicinity of the tropopause. These values are somewhat smaller than the widths of the radiactive transfer kernels at similar levels. Increasing the number of spectral intervals from 7 to 16 is found to produce only a marginal improvement in vertical resolution.
Conrath, B. J.↗