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Technical Paper

“Symbiose”: Technology Developments for Bioregeneration in Space

Dedicated technology has been developed to support long-term biological experiments on-board spacecraft. These developments include a microgravity compatible tubular photo bioreactor for the cultivation of micro algae at very high biomass concentrations and with very high gas exchange rates, a microgravity compatible gas / liquid phase separator which also works as a pneumatic low shear-stress pump, a microgravity compatible dehumidifier, and a maltose separating reverse osmosis unit. Integration of these technologies into a partially closed artificial ecosystem form the foundation of the SYMBIOSE concept (System for Microgravity Bioregenerative Support of Experiments).
Technical Paper

“Smart Panel” Electronic Circuit Breaker Control Technology

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).
Technical Paper

“Greater Than the Sum of its Parts” Integrated Flight Training/Aircrew Coordination

The requirement for crew resource management (CRM), or aircrew coordination training (ACT) in military parlance, has been well documented and attested to. In addition, aircraft systems training has become more intense and more in-depth in the new aircraft designs, especially in multi-crew and complex aircraft such as the MV-22 Osprey Tiltrotor. (see Figure 1) Former training systems detailed training procedures that called for classroom training and simulation/simulator training followed by flight training. Improvements in aircraft flight skills training provide increased flying training capability coupled with reduced training time by integrating a mixed simulation/flight training syllabus, e.g. two to three simulation periods followed by one or two flight training periods covering the same material/skills. In addition, the simulation training will introduce new skills; the following flight periods will further refine/hone those skills.
Technical Paper

“Flexible” Cargo Handling Systems for Standard-Body Airplanes

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.
Technical Paper

“Dynamic Analysis of Cabin Tilting System of Heavy Trucks Using ADAMS-View for Development of a Software Interface for Optimization”

Design of a Cabin Tilting System of heavy trucks, a multi degree of freedom mechanism, is a challenge. Factors like adequate tilting angle, cabin styling, packaging, non interference of tilting system with ride comfort, forces in the system, specifications of the hydraulic system, are all very important for designing the system. Numerous considerations make the design process highly iterative hence longer design time. This paper primarily focuses on Kinematics and Dynamic analysis of the system in ADAMS and validation of system with real time testing results. Intention of this work is to make a parametric ADAMS model and link it to a Knowledge Based Engineering application to facilitate designer to quickly carry out design iterations for reducing development time. The Knowledge Based Engineering software is made using object oriented language called ‘Object Definition Language’ which has been developed using C and C++ software languages.
Technical Paper

considerations of some JET-DEFLECTION PRINCIPLES for - - directional control - - lift

THE performance characteristics of various devices applicable for jet directional control, lift augmentation, and VTOL-STOL studied at the NACA Lewis Laboratory are discussed, including jet deflection devices applicable to the conventonal round nozzle and novel nozzle configurations. The results indicate that many of the deflection devices applicable to conventional nozzles can readily be used for directional control or lift augmentation. Other deflection devices, such as movable plug, internal flap, cylindrical thrust reverser, swiveled primary with fixed shroud, and 90 deg side-bleed nozzle, are limited in application to jet directional control or aircraft trim because the loss in axial thrust for a given deflection force is prohibitive or the maximum deflected force obtainable is limited.
Technical Paper

Zone of Influence of Porous Suction Tubes in Condensing Heat Exchanger for Space Systems

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.
Technical Paper

Zn-Ni Plating as a Cadmium Alternative

In a 2-year program sponsored by SJAC, an aqueous electroplating process using alkaline Zn-Ni with trivalent chromium post treatment is under evaluation for high strength steel for aircraft application as an alternative to cadmium. Commercial Zn-15%Ni rack/barrel plating solutions are basis for plating aircraft parts or fasteners. Brightener was reduced from the original formula to form porous plating that enables bake-out of hydrogen to avoid hydrogen embrittlement condition. Properties of the deposit, such as appearance, adhesion, un-scribed corrosion resistance, and galvanic corrosion resistance in contact with Al alloy, were evaluated. Coefficient of friction was compared with Cd plating by torque-tension measurements. Evaluation of the plating for scribed corrosion resistance, primer adhesion, etc. will continue in FY2007.

Zinc Phosphate Treatment Paint Base

This specification covers the requirements for producing a zinc phosphate coating on ferrous alloys and the properties of the coating.
Technical Paper

Zero-Waste PVD Cadmium for High Strength Steels

In spite of environmental issues related to cadmium and its electroplating process, electroplated cadmium is still extensively used in the aerospace and defense sectors. This trend is likely to continue especially for high strength steels because cadmium provides the best known corrosion and embrittlement protection for this application. Consequently, the environmental concerns related to the cadmium electroplating have been addressed using an alternative Zero-waste Physical Vapor Deposition (Z-PVD). This method does not use liquids, it recycles cadmium in situ, and is free of hydrogen embrittlement. The Z-PVD process is now in commercial production for the aerospace fasteners. The quality of the coatings has been at least equal to that of the electroplated cadmium.
Technical Paper

Zero-G Water Selection Separator: A Performance Tradeoff

This paper presents a trade-off study to select a water separator system for a 3-man, 140-day, zero-g mission. Included is a summary of feasible concepts, a compilation of data on existing hardware, and a comparison of the performance characteristics of each with respect to the overall system. Six approaches to zero-g water separation were considered and are discussed: hydrophobic/hydrophilic screens; integrated condenser-water separators; centrifugal separators; cellular sponges; vortex separators; and elbow separators. Some of these techniques have high-performance characteristics with regard to water removal efficiency. However, when reduced to hardware, these same techniques may not integrate well with the overall system. The system selected was the integrated condenser-water-separator. This system requires no power, has no moving parts, and has a very small envelope.
Technical Paper


This paper investigates the use of several zero-ozone depleting potential (zero-ODP) HFC refrigerants, including HFC-134a, HFC-227ca, HFC-227ea, HFC-236ea, HFC-236cb, HFC-236fa, HFC-245cb, and HFC-254cb, for centrifugal chiller applications. We took into account the thermodynamic properties of the refrigerant and aerodynamic characteristics of the impeller compression process in this evaluation.. For a given operating temperature lift, there are significant differences in the pressure ratio required by each refrigerant and this variation in pressure ratio directly affects compressor size, efficiency, and performance. A comparison of the HFC refrigerant candidates with CFC-114 shows that HFC-236ea, HFC-227ca and HFC-227ea are viable alternatives for centrifugal water chillers. HFC-236ea has properties closest to CFC-114, and will result in comparible performance, but will require a slightly larger impeller and a purge system.
Technical Paper

Yield Monitors, Combines, and Their Interactions

Instantaneous combine grain yield monitors need to provide reliable yield measurements since yield as a function of location is key information needed to manage fields by management zones. A scale and a yield monitor measured the same stream of grain and provided similar results when compared to each other. Data from either device may be misinterpreted if care in calibration and operation is not taken. Careful operators who pay attention to calibration, maintenance, and manufacturer's instructions will be required.