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This paper will discuss using Astronics “Smart Panel” illuminated control panels to control an electronic power distribution system. A discussion of wiring simplification, automatic control possibilities and real time load monitoring is presented. The challenges of retrofitting the system into older aircraft will be covered as well. The paper also explains Electronic Circuit Breaker technology, arc fault protection, panel lighting technologies, control bus options, displays, and human input technology (buttons and knobs).

This paper presents, chemistry, test data and processing procedures on a non toxic and environmentally friendly chrome-free conversion coating alternative with the same level of adhesion and secondary corrosion resistance as that found in chrome containing conversion coating systems. Test data from military and independent sources will be presented on secondary coating adhesion, electrical conductivity, filiform and neutral salt-spray corrosion resistance as compared to chromate based systems .on magnesium, aluminum and zinc and their respective alloys. The European “RoSH” initiative will not allow for the presence of any hexavalent chromium on imported electrical components as of July first of 2006. Trivalent chromium based systems generate hexavalent chromium due to the oxidation of the trivalent chromium and as such will not be allowed.

This paper describes some of the design solutions adopted in solving two major problems besetting man-powered aircraft in use: that of breakage and storage. It describes work leading up to the building and testing of “Phoenix”, a man-powered aircraft with a polyester-film inflatable wing. The paper deals mainly with aspects relating to the wing design and construction.

The ability to carry cargo efficiently in passenger aircraft has influenced airline economics to the point that optimisation of the freight capacity is mandatory. This document discusses the alternative loading possibilities in defined Lover Deck Compartments and their doors to cater for current and future trends in ULD dimensions. As a result items for study centred on: 1) Optimisation of the available volumes Freight capacity resulting in the selection of “Pallets”-doors for both the Forward and AFT Compartments. Flexibility to meet Freight and Baggage requirements. Possible load arrangements to optimize aircraft C of G 2) Bulk Cargo Compartment Additional LD3 Container position in AFT/Bulk compartment to cater for an uneven number of Baggage container, allowing the carriage of an additional pallet. What is regarded as an optimum is presented.

The manner in which the lower deck cargo compartments of standard-body airplanes are designed, equipped, and serviced has not changed appreciably over the past 50 years. A number of factors now at work within the air transportation industry are causing carriers and airplane manufacturers to explore alternative approaches to these tasks. This paper reviews these factors, presents a new approach to lower deck cargo handling systems design, and describes how this approach can be applied to standard-body airplanes.

This paper presents the derivation of the equations for circumferential, longitudinal and radial heat transfer conductance for a thin shell toroid or a segment of the toroid. A thin shell toroid is one in which the radius to thickness ratio is greater than 10. The equations for the surface area of a toroid or of a toroidal segment will also be derived along with the equation to determine the location of the centroid. The surface area is needed to determine the radial conductance in the toroid or toroidal segment and the centroid is needed to determine the heat transfer center of the toroid or toroidal segment for circumferential and longitudinal conductance. These equations can be used to obtain more accurate results for conductive heat transfer in toroid which is a curved spacecraft components. A comparison will be made (1) using the equations derived in this paper which takes into account the curvature of the toroid (true geometry) and (2) using flat plates to simulate the toroid.

Whether we live on land, underwater, or out there in space, what makes it possible is our ‘skin’. The one we were born with, the one we wear, the one we live in, and the one we travel in. The skin is a response to where we live: it protects as our first line of defense against a hostile environment; it regulates as part of our life-support system; and, it communicates as our interface to everything within and without. In the context of space architecture – we, our space suits, vehicles and habitats are all equipped with highly specialized ‘skins’ that pad us, protect us and become an integral part of the design expression. This paper approaches the subject from a holistic perspective considering ‘skins’ and their manifestation as structure, as vessel, as texture, and as membrane. The paper then goes on to showcase innovative use of materials in practice through two case studies: the ‘spacesuit’ and ‘inflatable habitats’.

THIS PAPER REPORTS on the present state of the art in the utilization of refractory metals for air frame and powerplant sheet metal components. By far the most promising of these metals to date is molybdenum. The mechanical and physical properties of molybdenum are well-suited for high-temperature service. The combination of relatively high thermal conductivity, low thermal expansion coefficient, good specific heat, and a reasonably high emissivity of a coated surface make this material suitable for exterior surface application on severely aerodynamically heated components. However, in its usable alloyed forms, molybdenum tends to behave in a brittle manner at room temperature, suffering from a high brittle-to-ductile transition temperature. Other unacceptable properties are the presence of laminations in the material, 45-deg preferred angle cracking, and difficulty of controlling interstitial alloying elements. The authors discuss each of these and the progress made in overcoming them

RADIATION can produce almost instantaneous failure of modern aircraft lubricants, tests at Southwest Research Institute show. Two types of failures demonstrated are rapid viscosity rise and loss of heat conductivity. Furthermore, it was found that lubricants can become excessively corrosive under high-level radiation. Generally speaking, the better lubricants appeared to improve in performance while marginal ones deteriorated to a greater extent under radiation. When the better lubricants were subjected to static irradiation prior to the deposition test, there was a minor increase in deposition number as the total dose was increased.

STRUCTURAL MATERIALS for Mach 3 jet transports pose difficult problems for the design engineer. Reasons for this problem are the incomplete information available on the many possible metals and the diversity of critical properties that are added by supersonic requirements. The material properties discussed in this paper include tensile strength, resistance to crack propagation, ease of fabrication, weldability, and thermal expansion. Cost factors are also considered. The structural configuration of the wing and fuselage is an example of the complexity of the material selection problem. The wing may be rigidity-critical, and the fuselage strength-critical; each requires diferent material properties to solve the problem.*

A “next generation” condensing heat exchanger for space systems has to satisfy demanding operational requirements under variable thermal and moisture loads and reduced gravity conditions. Mathematical models described here are used to investigate transient behavior of wetting and de-wetting dynamics in the binary porous system of porous tubes and porous cold plate. The model is based on the Richard's equation simplified for the zero-gravity conditions. The half-saturation distance or the zone of influence of the porous annular suction tubes on the cold-plate porous material will be in the range of 1 to 10 cm for the time scales ranging from 100 to 10,000 seconds and moisture diffusivity in the range of D = 10-4 to 10-6 m2/s.

This paper describes the testing of a waste management system designed and fabricated for use in a space vehicle. The system provides for the collection and inactivation of urine, feces, emergency diarrheal disorders, vomitus, and debris; the volumetric determination of each micturition; and onboard storage of the inactivated wastes within the waste management system compartment. The zero-gravity test program conducted in a KC-135 aircraft provided the primary verification of the performance of the waste collection and urine volume determination functions prior to actual space flight. The test hardware simulated the actual system to a high degree of fidelity with respect to operational characteristics of the airflow required in collection, mechanical functions and system pressure differentials, in order to minimize simulation errors.

Growth Temperatures And Lighting Intensity Are Key Factors That Directly Impact The Design, Engineering, And Horticultural Practices Of Sustainable Life-Support Systems For Future Long-Term Space Missions. The Effects Of Exposure Of Lettuce (Cv. Flandria), Radish (Cv. Cherry Bomb Ii). And Green Onion (Cv. Kinka) Plants To Controlled Environment Temperatures (Constant Day/Night Temperature Of 22, 25, Or 28 °C) And Lighting Intensities (8.6, 17.2, Or 25.8 Mol M−2 D−1 Photosynthetic Photon Flux [Ppf]) At Elevated Co2 (1200 µMol Mol−1) Was Investigated To Ascertain Overall Yield Responses. Following 35 Days Growth, The Yields Of Lettuce Indicated That Increasing The Growing Temperature From 22 To 28°C Slightly Increased The Edible Fresh Mass Of Individual Plants. However, Even Though Lettuce Plants Grown Under High Ppf Had The Highest Fresh Mass, The Resultant Increase In The Incidence And Severity Of Tipburn Reduced The Overall Quality Of The Lettuce Head.

Controlling rivet tolerances, and the hole tolerances that these rivets are inserted into, are some of the most important requirements in the manufacture of aircraft. Because of the laminar air flow over the outside of the skin in all aircraft, and the stealth requirements of military aircraft, the rivets must sit flush with the Outside Mode Line of the exterior skin. This countersink depth must be tightly controlled in tolerance, both in the hole diameter & countersink, and also in the manufacture of the rivets. In the past, the aircraft OEM's have driven, independently, the rivet manufacturer and the machine manufacturer drilling the holes, to control tighter and tighter tolerances. The conventional way to get better performance is to implement SPC independently into the rivet manufacturing process and also into the machine hole drilling process. Let's consider first the rivet manufacturing process.

In order to provide effective cooling for astronauts during extravehicular activities (EVAs), a liquid cooling and ventilation garment (LCVG) is used to remove heat by a series of tubes through which cooling water is circulated. To better predict the effectiveness of the LCVG and determine possible modifications to improve performance, computer simulations dealing with the interaction of the cooling garment with the human body have been run using the Wissler Human Thermal Model. Simulations have been conducted to predict the heat removal rate for various liquid cooled garment configurations. The current LCVG uses 48 cooling tubes woven into a fabric with cooling water flowing through the tubes. The purpose of the current project is to decrease the overall weight of the LCVG system. In order to achieve this weight reduction, advances in the garment heat removal rates need to be obtained.

The wireless Spread Spectrum Ground Communication (SSGC) system will contribute to the enhancement of aircraft maintenance, flight, dispatch, and cargo operations efficiency. A concept layout of the wireless SSGC system implementation in an airport environment is illustrated in Figure 1. The SSGC system will provide both text/graphics data transmission and voice communication for flight crew, maintenance, and dispatch personnel in the airport gate environment. This system will link ground information system and onboard avionics systems, and provide access by ground crew to an information database through portable graphics terminals. The objective is to integrate both airborne avionics, ground crew, and ground based resources into a seamless operating system.

Results of a brief study program to devise and evaluate new structural materials and concepts for a subsonic, transport-type aircraft are presented. Comparisons of several wing concepts to the state-of-the-art baseline concept indicate a weight saving of 10%, but with corresponding total cost increases of 50-75%. One fuselage concept indicates a 7% weight saving with a 5% total cost saving. Corresponding aircraft performance payoffs with and without resizing are also established. The overall payoffs are somewhat nominal, based on the new concept impact on participating structure only. Both baseline and new concept analyses are based on a common set of requirements for ultimate strength, fatigue life, damage tolerance, and flutter rigidity. The study is directed to metallic concepts.

As the amount of embedded software in the vehicle increases dramatically, the software design and development tasks are daunting. Over the past few years, the automotive industry has taken measures to increase software re-use and promote competition among basic software vendors. If AUTOSAR has emerged as the de-facto standard for embedded automotive software development, there are numerous challenges ahead as the standard assumes the availability of both the hardware and the associated abstraction layer among others. This can be problematic for developers. Furthermore, engineers may be interested in performing early what if tests - early functional tests - to ensure that their strategies will not cause problems later in the development process. As always, errors are less costly to fix if they can be caught early. With AUTOSAR several thousand parameters have to be configured in about 60 modules.

This paper is concerned with the development of statistical models for the gust field in the lowest 300 ft of the atmosphere. It presents some of the highlights of the underlying physics principles, what is known about gusts, and how gusts affect aircraft. The difficulties of developing gust models are accounted for by the lack of data in particular areas and thus direct attention to the work required to provide the needed information.