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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 STANDARD ESTABLISHES THE DIMENSIONAL AND VISUAL QUALITY REQUIREMENTS, LOT REQUIREMENTS, AND PACKAGING AND LABELING REQUIREMENTS FOR D-RINGS MOLDED FROM MIL-P-25732 ACRYLONITRILE BUTADIENE (NBR) RUBBER. IT SHALL BE USED FOR PROCUREMENT PURPOSES.

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.

During several ISS missions, there were false alarms at both US and Russian smoke detectors. High local airborne particulate concentrations and interior deposits are considered the causes for such anomalies. Alternatives are proposed to replace or complement these faulty smoke detectors. The entrained zeolite particles may play a role in causing problems with check valves and air save pumps in CDRA and Vozdukh. Another incidence has been the dispersion of particulates out of Metox regeneration oven. Particulate matters with aerodynamic diameter of 15 microns and above, which normally settle down on earth, stay airborne under micro-gravity and thereby cause the above-mentioned nuisances. The motion of such a particle along a gas stream with an initial velocity can be expressed by theoretical equations. Stokes' Law leads to the descriptions of inertial precipitation of aerosols that are important in solving the issues.

This Life Support Laboratory consists of a simulator of the spacecraft called Nautilus, which houses Air Revitalization Subsystem, Atmospheric Control and Supply, and Fire Detection and Suppression in the Equipment Area. There are supporting facilities including a Human Metabolic Simulator, simulated Low and Moderate Temperature Coolant Loop, chemical analysis bench, purified water supply, vacuum and gas supplies. These facilities are scheduled to be completed and start to operate for demonstration purposes by March 2005. There are an ARES Ground Model (AGM) and a Trace Contaminant Control Assembly in the ARS. The latter will be integrated with the AGM and a Condensing Heat Exchanger. The unit of AGM is being engineered, built, and will be delivered in early 2005 by EADS Space Division. These assemblies will be operated for sensitivity analysis, integration and optimization studies. The main goal is the achievement for optimal recovery of oxygen.

HEAT TRANSFER causes loading and starting design problems in large missile systems powered by cryogenic propellants. This manifests itself during loading as effective density variation, violent surface conditions, boiloff, and ice formation — problems which may be solved by insulating the tank. During starting it causes overheating and caviation — effects which may be reduced by recirculators and subcooled charge injections. The study described in this paper centers around liquid oxygen and its variations in heat flux rate, which affect liquid density, surface condition, and replenishing requirements. The problem areas are made apparent by consideration of a hypothetical missile system.*

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.

Spacecraft life support equipment is often challenged with two phase flow, where liquid and gas exist together. In the zero gravity environment of an orbiting spacecraft, the behavior of a liquid/gas interface is dominated by forces not usually observed in one “G” due to the overwhelming effects of gravity. The normal perceptions no longer apply. Water does not run down hill and bubbles do not rise to the surface. Surface energy, capillary forces, wetting characteristics and momentum effects predominate. Techniques and equipment have been developed to separate the liquid/gas mixture into its constituent parts with various levels of efficiency and power consumption.

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.

The YF-23A Advanced Tactical prototype Fighter was a revolutionary statically unstable, twin engine aircraft that cruised at supersonic speeds without afterburner and was designed to out maneuver opponents at subsonic and supersonic speeds. Combining these capabilities into a chosen aircraft configuration demanded a flight control hydraulic system of unprecedented power and performance. Increased system reliability, and reduced maintenance also presented a challenging system design. The YF-23A's unique flight and maneuvering envelope required high surface rates and large actuator excursions at low flight speeds, as well as power to generate increased hinge moments at supersonic speeds. To achieve these specifications, Northrop developed a hydraulic system that utilized flow conservation and prioritization techniques. The hydraulic system configuration was maintained by using hydrologic, as well as electronic control.

This paper presents lessons learned from flight testing of the YA-10B Single Seat Night Attack (SSNA) testbed. The generic night attack avionics suite in the YA-10B was used to provide a workload baseline for use in future night attack programs. Pilot rating scales and physiological data were used to construct the workload data base.

X-ray is an indispensable aid in locating and determining the extent of incipient failures in structure which is inaccessible by position or covered by multiple layers of metal. It is also the most feasible method for checking oil coolers for contamination; bonded honeycomb panels for water; fuel lines for erosion; and with a 360 deg emission tube, fuselage frames for structural integrity without removing the interior upholstery and panels from the passenger compartment or cargo compartments.

The X-29 Fuel/Auxiliary Oil Thermal Management System provides total aircraft accessory oil cooling, including both flight and combined hydraulics, Integrated Drive Generator oil, and Accessory Drive Gearbox oil, with onboard fuel. Fuel cooling rates that are independent of engine demand are achieved through the use of a recirculation loop. Recirculation is minimized by maintaining the engine fuel inlet temperature at the maximum allowable. Fuel cooling results in lower, more uniform subsystem oil temperatures, less ram drag, and smaller, lighter-weight heat exchangers. Initial design studies and laboratory development testing will be discussed, along with comparisons of analytical predictions with flight test results.

This SAE Aerospace Standard (AS) covers 6-point and 12-point flare nut crowfoot, flare nut wrenches, double end flare nut wrenches, combination box end and flare nut wrenches, combination open end and flare nut wrenches, and ratcheting flare nut wrenches that are designed with the following requirements: (a) non-distorting usage; (b) possessing the strength, clearances, and internal wrenching design to be used on hydraulic tube fittings that conform to the requirements of SAE J514 and ISO 8434-2; and (c) transmitting torque to tube fittings without bearing on the apex of fitting wrenching points. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

This SAE Aerospace Standard (AS) covers 12-point open box end crowfoot, flare nut, double open box end, combination box and open box end, and ratcheting open box end wrenches that are designed with the following requirements: a Nondistorting usage b Possessing the strength, clearances, and internal wrenching design to be used on hydraulic tube fittings that conform to the requirements of SAE J514. c Transmitting torque to tube fittings without bearing on the apex of fitting wrenching points. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

This SAE Aerospace Standard (AS) covers 12 point flare nut crowfoot, flare nut wrenches, double end flare nut wrenches, combination box and flare nut wrenches, and ratcheting flare nut wrenches that are designed with the following requirements: a. Non-distorting usage b. Possessing the strength, clearances, and internal wrenching design to be used on hydraulic tube fittings that conform to the requirements of SAE J514. c. Transmitting torque to tube fittings without bearing on the apex of fitting wrenching points. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

This SAE Aerospace Standard (AS) covers 12 point flare nut crowfoot, flare nut wrenches, double end flare nut wrenches, combination box and flare nut wrenches, and ratcheting flare nut wrenches that are designed with the following requirements: (a) Non-distorting usage; (b) Possessing the strength, clearances, and internal wrenching design to be used on hydraulic tube fittings that conform to the requirements of SAE J514; (c) Transmitting torque to tube fittings without bearing on the apex of fitting wrenching points. Inclusion of dimensional data in this document is not intended to imply that all of the products described herein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.

The first flight of a delta wing aircraft took place in the United States at the Muroc AFB Flight Test Center on 18 September 1948. The aircraft, Convair No. 7002, Air Force S/N 46-682 and designated the XF-92A was piloted by Convair's Manager of Flight Research, E.D. “Sam” Shannon. The author witnessed this historic flight as a Flight Test Engineer on the project. Studies and wind tunnel tests for a supersonic interceptor were conducted at the Vultee Division of Consolidated Vultee Aircraft Corporation (Convair) in 1945. These studies led to the selection of the 60° delta wing plan form. This paper reviews the major differences between the thin wing XF-92A and the thick wing DM-1 glider (never flown) designed by Alexander M. Lippisch in Germany at the close of World War II. The XF-92A used a fully hydraulic irreversible control system for its elevons and rudder. The only airplanes up to this time with fully hydraulic controls were the Northrop XB-35 and the YB-49 flying wings.

Cockpits have changed dramatically over the last ten years. The electro-mechanical instruments have largely been replaced with electro-optical controls and displays. This change in the pilot-vehicle interface, coupled with a second development, the emergence of a very powerful airborne computer system, an Electronic Crewmember, has had a significant impact on workload in the cockpit. Workload has shifted from physical to mental, and many workload measurement tools applied previously may no longer be appropriate. This paper discusses the prediction, real time measurement and dynamic allocation of cockpit workload in an aircraft with a crew of two -- one human and one electronic.