Magazine

Two reports describe a Rayleigh-scattering attitude sensor (RSAS) - an optoelectronic instrument for determining the orientation of a spacecraft. An RSAS comprises a telescope/video-camera/image-digitizer combination that is mounted on the spacecraft and that captures images of the limb of...

A report describes experiments in which planar laser-induced fluorescence (PLIF) of hydroxyl radicals was used to study the structures of flames in burner test rigs (a flame-tube combustor and a sector combustor) under conditions like those in combustors of aviation gas-turbine engines. The PLIF...

A paper discusses the excessive conservatism that has long been suspected to exist, because of the use of conventional (deterministic) safety factors, in the analysis and design of quasi-static structures. The origin of this conservatism is identified as a violation of statistical error-propagation...

A control system that includes a single thermal source has been designed to afford precise control of the temperature of a fluid flowing in a closed-loop system. Similar control systems could make it possible to increase production levels and to reduce risks in industrial situations in which...

A report describes an experimental study of the low-temperature electrical characteristics of commercial Li/MnO2, Li/CFx, Li/SO2, Li/SOCl2, and Li/BCX primary electrochemical cells. These high-energy-density cells are under consideration for use as lightweight, compact electric-power sources...

A paper summarizes a continuing program of vibro-acoustic testing of two aircraft fuselage structures: (1) a 12-ft (3.7-m)-long generic aluminum test-bed cylinder that contains stiffening rings and stringers and (2) the 40-ft (12.2-m)-long fuselage of a 10-passenger turboprop airplane, made of...

A report describes a continuing program of development of flight software for the attitude-control system (ACS) and the command-and-data-handling (C&DH) system of a prototype standard spacecraft of the Small Explorer (SMEX)-Lite class. Both the C&DH and ACS parts of the software...

Probabilistic Ceramic Matrix Composite Analyzer (PCEMCAN) is a user-friendly computer program that predicts uncertainties in the mechanical and thermal properties of ceramic-matrix composite (CMC) materials. These materials are candidates for fabrication of structural components that will be...

Version 1.4 of the Launch Vehicle Loads Analysis for Preliminary Design (VLOADS 1.4) computer program calculates in-flight launch-vehicle structural loads (that is, spacecraft-launching rockets) for preliminary design. The program can also be used to calculate structural loads in upper stages and...

When a problem such as breaking bellows couplings threatens to halt a machinery production line, it is necessary to look beyond the obvious. In an application in which the coupling works on a Heidenhain encoder for an X-Y table that positions circuit boards, representatives of the user company and of...

The Automated Test Monitor computer program provides for continuous monitoring of the operations of a complex system (e.g., a spacecraft). This program implements a rigorous analytic (instead of an ad hoc) technique that prescribes exactly how to express requirements for the operation of...

The Mission Planning Graphical Tool (MPGT) computer program provides a mouse-driven graphical representation of data on a spacecraft and its environment, for use in planning a space flight. MPGT is designed to be a generic software tool that can be configured to analyze any specified...