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Technical Paper

some development problems with Large Cryogenic Propellant Systems

1960-01-01
600022
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.*
Technical Paper

a study of Self-Contained Starting Systems for Turbojet and Turboprop Engines

1960-01-01
600011
SUBSTANTIAL POWER is necessary to start the modern jet engine. Thus, starting equipment has become a major concern of air transport operators. This paper discusses the equipment used with self-contained starting systems. The authors discuss and evaluate a variety of self-contained systems: combustor, fuel-air combustion, cartridge, liquid propellant, hydraulic supported by auxiliary power units, and electric supported by APU. Possible future systems are: self-breathing systems, oxygen combustors, and liquid-oxygen-water-fuel combustors. It is emphasized that the choice of a starting system for a particular aircraft will depend on aircraft characteristics and the aircraft's intended use.*
Technical Paper

Zn-Ni Plating as a Cadmium Alternative

2007-09-17
2007-01-3837
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.
Technical Paper

Zero-Waste PVD Cadmium for High Strength Steels

1998-11-11
983137
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 Liquid Propellant Orientation by Passive Control

1964-01-01
640239
This paper discusses the advantages and problems associated with the use of “passive” liquid containment systems that utilize liquid intermolecular forces for propellant orientation in reduced or zero gravity environments. Liquid orientation is required to provide reliable engine restart and tank venting operations of space vehicle propulsion systems. Various liquid containment system concepts, and associated design criteria, are presented and general problem areas of interface stability, liquid slosh, and effects of thermal energy are described. Descriptions of present and planned test facilities designed to provide reduced gravity environments and extended time durations are included. It is concluded that additional design criteria in the problem areas discussed must be obtained before “passive” liquid containment systems can replace systems now used in reduced or zero gravity environments.
Technical Paper

ZENITH: A Nano-Satellite for Atmospheric Monitoring

2015-09-15
2015-01-2395
Abstract This paper describes the ZENITH Nano-Satellite cum planetary atmospheric entry vehicle, called CanSat, the first Nano-Satellite project that has been developed by Delhi Technological University (Formerly Delhi College of Engineering), India. The satellite will function for monitoring the concentrations of various gases in the atmosphere. For this, the satellite consists of arduino microcontroller interfaced with the various Micro-electromechanical system (MEMS) gas sensors for measuring the concentrations of various gases such as carbon dioxide, carbon monoxide, methane, nitrous oxides, ozone, etc. The data obtained from the CanSat will be transmitted to the ground station where all the data will be stored and also the locations will be stored using GPS sensor. The academic goal of this project is to recruit students to the field of space science and technology.
Article

X marks the spot

2018-03-22
LiquidPiston Inc. has developed a new engine that can run on multiple fuels, including diesel, jet fuel, and gasoline. This platform uses an optimized thermodynamic cycle and a new rotary engine architecture and could increases flight endurance over conventional UAV engines by greater than 50%.
Standard

Wiring, Positioning, and Support Accessories

2010-05-12
HISTORICAL
AS23190A
AS23190 is a procurement specification that covers a series of plastic and metal components and devices used for the tying, positioning, and supporting cable, cable assemblies, wire, and wire bundles in electrical, electronic and communication equipment, and in interconnection systems.
Standard

Wire, Electrical, Fluoropolymer-Insulated, Copper or Copper Alloy

2018-05-16
CURRENT
AS22759D
AS22759 specification covers fluoropolymer-insulated single conductor electrical wires made with tin-coated, silver-coated, or nickel-coated conductors of copper or copper alloy as specified in the applicable detail specification. The fluoropolymer insulation may be polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), polyvinylidene fluoride (PVF2), ethylene-tetrafluoroethylene copolymer (ETFE), or other Fluoropolymer resin. The fluoropolymer may be used alone or in combination with other insulation materials. These abbreviations shall be used herein. When a wire is referenced herein, it means an insulated conductor (see 7.7).
Standard

Wire, Electrical, Fluoropolymer-Insulated, Copper or Copper Alloy

2014-10-27
HISTORICAL
AS22759C
AS22759 specification covers fluoropolymer-insulated single conductor electrical wires made with tin-coated, silver-coated, or nickel-coated conductors of copper or copper alloy as specified in the applicable detail specification. The fluoropolymer insulation may be polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), polyvinylidene fluoride (PVF2), ethylene-tetrafluoroethylene copolymer (ETFE), or other Fluoropolymer resin. The fluoropolymer may be used alone or in combination with other insulation materials. These abbreviations shall be used herein. When a wire is referenced herein, it means an insulated conductor (see 7.7).
Standard

Wire, Electrical, Fluoropolymer-Insulated, Copper or Copper Alloy

2011-09-06
HISTORICAL
AS22759B
AS22759 specification covers fluoropolymer-insulated single conductor electrical wires made with tin-coated, silver-coated, or nickel-coated conductors of copper or copper alloy as specified in the applicable detail specification. The fluoropolymer insulation may be polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), polyvinylidene fluoride (PVF2), ethylene-tetrafluoroethylene copolymer (ETFE), or other fluoropolymer resin. The fluoropolymer may be used alone or in combination with other insulation materials.
Standard

Wire, Electrical, Fluoropolymer-Insulated, Copper or Copper Alloy

2006-12-05
HISTORICAL
AS22759A
AS22759 specification covers fluoropolymer-insulated single conductor electrical wires made with tin-coated, silver-coated, or nickel-coated conductors of copper or copper alloy as specified in the applicable detail specification. The fluoropolymer insulation may be polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), polyvinylidene fluoride (PVF2), ethylene-tetrafluoroethylene copolymer (ETFE), or other fluoropolymer resin. The fluoropolymer may be used alone or in combination with other insulation materials.
Standard

Wire, Electrical, Fluoropolymer-Insulated, Copper or Copper Alloy

2001-07-01
HISTORICAL
AS22759
This specification covers fluoropolymer-insulated single conductor electrical wires made with tin-coated, silver-coated, or nickel-coated conductors of copper or copper alloy as specified in the applicable specification sheet. The fluoropolymer insulation of these wires may be polytetrafluoroethylene (PTFE), fluorinated ethylene propylene (FEP), polyvinylidene fluoride (PVF2), ethylene-tetrafluoroethylene copolymer (ETFE), or other fluoropolymer resin. The fluoropolymer may be used alone or in combination with other insulation materials.
Standard

Wire, Electrical, Crosslinked Polyalkene, Crosslinked Alkane-Imide Polymer, or Polyarlyene Insulated, Copper or Copper Alloy

2011-08-11
CURRENT
AS81044A
This specification covers single conductor electric wires made as specified in the applicable specification sheet with tin-coated, silver-coated, or nickel-coated copper or copper alloy conductors insulated with crosslinked polyalkene, crosslinked alkane-imide polymer, or polyarylene. The crosslinked polyalkene, crosslinked alkane-imide polymer, or polyarylene may be used alone or in combination with other insulation materials as specified in the specification sheet.
Standard

Wire, Electric, Polyvinyl Chloride Insulated, Copper or Copper Alloy

2011-01-14
CURRENT
AS50861A
This specification covers polyvinyl chloride insulated single conductor electric wires made with tincoated copper conductors or silver-coated copper alloy conductors as specified in the applicable detail specification. The polyvinyl chloride insulation of these wires may be used alone or in combination with other insulating or protective materials.
Standard

Wire, Electric, Polyvinyl Chloride Insulated, Copper or Copper Alloy

1998-03-01
HISTORICAL
AS50861
This specification covers polyvinyl chloride insulated single conductor electric wires made with tin-coated copper conductors or silver-coated copper alloy conductors as specified in the applicable military specification sheet. The polyvinyl chloride insulation of these wires may be used alone or in combination with other insulating or protective materials.
Technical Paper

Wind and Temperature Database for Flight Planning

1981-10-01
811068
This paper discusses the importance of enroute wind conditions and the need for a wind measurement system which provides accurate and timely observations of wind and temperature conditions aloft. Recent advances in remote measurement of winds, temperature, and humidity such as the Stratospheric-Tropospheric radars and profilers developed at the National Oceanic and Atmospheric Administration’s Environmental Research Lab form the basis of such a system. A domestic system could and should be established using these devices together with a near real time winds aloft data dissemination network. Estimates of the saving in aircraft fuel consumption benefits range from 1 to 3 percent per year, or from $ 100 to $ 300 million for U.S. aviation system users at current prices and consumption.
Technical Paper

What Forces Will Shape Tomorrow's Short-Haul Aircraft

1984-10-01
841449
Abstract Commuter/regional airlines profits depend largely upon equipment which helps increase revenue a/o minimize operating costs, with former seen more critical. Airframe/component reliability is priority requirement. Maintenance schedules, a/c performance and pax appeal must mesh with demands of high weekday/daytime cycles between congested hubs and rural airports. Manufacturers help regionals most with a/c optimizing a blend of: payload, pressurized pax comfort, ops flexibility and fuel efficiency, progressive/simplified maintenance, airframe/component durability and reliability, low parts count, QC cabin for cargo/charter off-peak opportunities.
Technical Paper

Weight Optimization of Fork and Axle of Main Landing Gear for an Unmanned Aerial Vehicle by Finite Element Analysis

2017-07-10
2017-28-1949
Abstract Unmanned Aerial Vehicles (UAV) are being deployed in military, law enforcement, search & rescue, scientific research, environmental & climate studies, reconnaissance and other commercial and non-commercial applications on a large scale. A design and development of landing gear system has been taken up for a UAV. This paper presents the design optimization of structural components of Wheel-Brake & Fork assembly pertaining to the Main Landing Gear (MLG) for a UAV. The wheel, fork, axle and brake unit constitute the wheel assembly. The wheel-brake assembly is assembled with the strut assembly and forms the Landing gear system. The Fork is the connecting member between the shock strut and the axle containing the wheel-brake assembly. As the fork and axle are subjected to shock loads while landing, the strength of these components are very much essential to withstand the dynamic loads.
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