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A reference architecture model of a typical fire control system has been established with the Real-time Object-Oriented Modeling (ROOM) environment, ObjecTime. An external graphics user interface (GUI) has also been developed to communicate with the reference architecture, thus making the reference architecture an ideal tool to test a specific design based on the architecture implementation. The GUI also communicates with an independent ballistics calculation program to send the target parameters and receive the ballistics calculation results. The ObjecTime model, the GUI, and the external ballistics calculation program constitute a demonstration system for the fire control reference architecture.

This paper describes a high frame rate focal-plane-array range camera module, based on optical time-of-flight measurement, along with machine vision algorithms that take advantage of the real-time 3D information. The utility of such technology is demonstrated in an advanced backup safety system. This system detects obstacles lying on the ground as well as tracks moving objects. Using dual detection criteria, the system outperforms existing backup proximity sensors. Based on 3D imagery collected from a rear-viewing camera configuration, we evaluate the detection and tracking accuracy for varying object sizes and ranges. Operational experience shows that our time-of-flight range camera can be a cost-effective and reliable component of intelligent automotive safety and driver assist systems.

This work reports a conception phase of a piston engine global model. The model objective is forecast the motor performance (power, torque and specific consumption as a function of rotation and environmental conditions). Global model or Zero-dimensional is based on flux balance through each engine component. The resulting differential equations represents a compressive unsteady flow, in which, all dimensional variables are areas or volumes. A review is presented first. The ordinary differential equation system is presented and a Runge-Kutta method is proposed to solve it numerically. The model includes the momentum conservation equation to link the gas dynamics with the engine moving parts rigid body mechanics. As an oriented to objects model the documentation follows the UML standard. A discussion about the class diagrams is presented, relating the classes with physical model related. The OOP approach allows evolution from simple models to most complex ones without total code rewrite.

This paper describes the NASA/JSC Research Technology Opportunity Program (RTOP) activity to assess the supportability of space systems throughout their life cycles. Supportability analyses for space systems present unique attributes and problems. The OSMOSSYS (Object oriented Simulation of Maintenance and Operations for Space Systems) was developed using object-oriented design concepts to provide NASA an analysis tool which addresses the question “Will a proposed space facility be able to successfully perform the missions for which it is designed?” This model integrates the complete configuration of the system including the reliability and maintainability characteristics of each component, the logistics support, and the mission operations of the facility to assess the success rate of the planned mission(s). Two parallel design processes are being utilized; developing core modules utilizing C + +, and incorporating as much code and ideas as possible from existing NASA models.

As ALS goals branch out to extended missions to the moon and Mars, concurrent science and engineering projects take center stage in the development of new ALS technology. It is necessary to optimize the interdisciplinary research activities in order to ensure ALS research goals are met in a timely manner, and to guarantee the reliability of future long term missions. The SSM team of the NJ-NSCORT has developed an internet software platform capable of performing a systems level analysis of the ALS research activity. The information produced by the analysis can assist ALS researchers in the streamlining of research activity.

In the last decade, significant aerodynamic and manufacturing progress has been made in the area of achieving natural laminar flow over practical swept and unswept lifting surfaces. Further significant reduction in total aircraft drag is predicted by achieving significant amounts of additional natural laminar flow also over fuselages and other nonlifting airframe components. To date, only limited experimental results are available that examine the applicability of laminar flow over nonaxisymmetric fuselage shapes. The paper presents details of a cooperative NASA/Cessna flight experiment using a light twin-engine propeller-driven aircraft, to investigate transition location and transition mode over the nonaxisymmetric fuselage forebody. A discussion is given of the transition-instrumentation layout and the planned flight-test matrix.

Being a believer in ever looking forward, with the use of history only as a means for avoiding mistakes of the past, I plan to concentrate on identifying opportunities for further advancements in air transportation technologies--opportunities which appear to me to be worthy of professional effort of substance. With respect to broad experience of the past fifty-five years, during which I have been active in the air transport industry, I have come to be a great believer in the adage: “LEARN ALL YOU CAN ABOUT THE OTHER GUY'S MISTAKES, YOU'LL NEVER LIVE LONG ENOUGH TO MAKE THEM ALL YOURSELF.” - Author unknown

The purpose of this paper is to bring together for review the several safety aspects of air transport design and operation. The aspects discussed consist of items that do not fall readily into any major airline group or classification and which are generally of a controversial nature. Due credit is given to the remarkable maintenance, operation, and control of military aircraft. Crash evacuation (and in-flight evacuation), pilot limitations, and design specifications in relation to safety practices are among the topics discussed.

Significant freezing drizzle or supercooled large droplet (SLD) conditions were encountered during an FAA certification flight test of the Sino Swearingen Model SJ30-2 airplane. Flaps and slats were extended to simulate an approach in icing conditions. The freezing drizzle was embedded in a relatively small portion of a stratiform cloud in which the airplane was orbiting to maintain the required icing conditions for the test. Although efforts were made to avoid this portion of the cloud once recognized, the test was completed with a total of about six minutes of SLD exposure. A ridge accreted on the thermally anti-iced slat, a result which had not been observed in a prior encounter at similar liquid water content and temperature. Post-encounter handling qualities evaluations, including an approach to stall warning, revealed normal flight characteristics. When slats were retracted, the slat ridge shed quickly.

An investigation of the effects of severe in-flight weather environments on composite structures has been conducted as part of the NASA-Langley Research Center Storm Hazards Program. The on-going program uses an extensively-instrumented F-106B airplane to make thurderstorm penetrations. The vertical fin cap was chosen for the experimental composite structure because of the likelihood of lightning strike attachments and the ease of component replacement. Three components were flown and investigated. The first was the U.S. Air Force production glass/epoxy fin cap which was flame-sprayed by NASA with aluminum for lightning protection. The second fin cap was fabricated with Kevlar/epoxy fabric skins and used an aluminized glass cloth for lightning protection. The third fin cap was fabricated with graphite/epoxy fabric skins with no lightning protection. All three components were exposed to high rain rates and direct lightning strikes.

The high level of crashworthiness of child restraining devices (CRDs) mandated by FMVSS Ho. 213-80, and the dynamic test procedure adopted voluntarily by the industry before 213-80 went into effect, do not necessarily transfer from the laboratory to the family automobile. Correct use of CRDs is essential; misuse reduces or could even defeat the protective potential. To establish the magnitude of one part of the misuse problem, 23 observers in 12 states examined installation of CRDs in the forward-facing “toddler” mode for errors in seat belt routing and top tether installation. Of the 3233 crashworthy CRDs observed, 51% required a tether strap. Correct use of tethers was noted in only 16% of these. Of the 2323 CRDs examined for seat belt as well as tether installation, 75% were found to have errors in belt routing, tether use, or both. The consequences of misuse are touched upon, possible reasons for misuse are discussed, and remedies are suggested.

The process of analyzing hundreds of aircraft accidents has led to a five-factor model of the causes of pilot performance breakdowns. Obstacles to performance are one of the five major factors in the model. Seven major groupings of obstacles or obstructions to performance are identified. Each of the seven major groups are further delineated as to specific types of obstacles which may inhibit performance. These effects are discussed, along with suggestions for minimizing or removing the presence of the obstacles and obstructions.

Material manufacturers and suppliers are surprised when a material commonly provided to industry is not approved for use on manned spacecraft. Often, the reason is a lack of test data in environments that simulate those encountered in space applications, especially oxygen-enriched conditions, which significantly increase the likelihood of combustion and the propagation of fire. This paper introduces requirements for flight approval of non-metallic materials, introduces testing requirements, describes procedures for submitting materials for testing, outlines options if a material fails testing, and introduces the Materials and Processes Technical Information System (MAPTIS), a database housing all test data produced in accordance with NASA-STD-6001, Flammability, Odor, Offgassing, and Compatibility Requirements and Test Procedures for Materials in Environments that Support Combustion [1].

The titanium is on excellent material for fabrication of aerospace springs in substituting to steels, due to its high corrosion resistance, 60% lower density, and lower elastic modulus. The production of the titanium alloys by powder metallurgy (M/P), starting from the elemental powders is a feasible route considering its lower costs and versatility. In this work, results of the Ti-3Al-8V-6Cr-4Mo-4Zr (β-C) and Ti-35Nb-7Zr-5Ta alloys production are presented. Samples were cold isostatic pressing (350 MPa) with subsequent densification by sintering at 1200, 1400 and 1500 °C, in vacuum. Sintered samples were characterized for phase composition, microstructure and microhardness by X-ray diffraction, scanning electron microscopy and Vickers indentation, respectively. Density was measured by Archimedes method. It was shown that the samples were sintered to high densities and presented homogeneous microstructure.

Particles e.g. Diamonds or Synthetic Diamonds (CBN) can be occluded in a controlled low stress Nickel Sulfamate deposit thru the use of a universal fixture design which provides for solution flow thru the particles pressed against the cathode. Methods of chemical manufacturing of Nickel Sulfamate and the controls in manufacturing and plating are discussed.

Safe work time limits for persons wearing US Army's Self Contained Toxic Environment Protective Outfit (STEPO) were developed from human tests and human simulation. STEPO, a Level A HAZMAT protective garment, has CO2 scrubber, O2 supply and upper body liquid cooling. Rest/treadmill-exercise (10/20 min) cycle test results for a limited range of conditions were extended by simulating human responses to more environments. A rational 5 compartment lumped parameter thermo-physiological model was adapted to simulate responses with STEPO. The model's output showed close conformity with measured core temperatures and heart rates. The safe working time criterion was for the core temperature and heart rate not to exceed 38.3°C and 150bpm. For example, at 27 and 38°C the resulting recommended work limits are 240 and 70 min, respectively.

Human impact injury and survival tolerance levels for various crash conditions are presented on the basis of currently available biomedical and biomechanical knowledge. Consideration of physical factors influencing trauma-including body orientation, restraint system, magnitude, distribution, and time duration of deceleration-are summarized, as well as tabulations and sources of data for both whole body and regional impact tolerances. These biological data concerning human impact tolerances are provided as guidelines for improved engineering design of general aviation crashworthiness.

The Space Shuttle reduces operational space costs and makes space accessible to more personnel. Mission objectives dictate how occupant safety is achieved. High standards of occupant safety in a space vehicle's hazardous environment, in turn, greatly influence design. Protection from some hazards, like fire, explosion, depressurization, toxicity, control loss, and radiation are controlled similarly to past space programs but with some deviations from aircraft practices. Man is another hazard source which is controlled primarily by training and proper procedures.

Testing the underwater launching of Polaris had to be done from an unmanned and remotely operated underwater facility before test missile launchings from a submarine could be safely and reliably accomplished. The development and operation of equipment to perform these tests rivaled and perhaps surpassed the technical problems of the tactical missile launcher. It was necessary to duplicate the undersea environment of the submarine, including water depth and relative ship-water motion from the effect of surface waves and from the way of the submarine. Further, it was necessary to arrest the fallback of inert test vehicles after launch to avoid damage to the launcher and to allow postlaunch evaluation of the structural integrity of the test vehicle. The servicing of the surfaced launch vessel was accomplished at a catamaran type work barge, and the operation of the submerged launch vessel was accomplished from a monitor barge.