Refine Your Search

Topic

Author

Affiliation

Search Results

Technical Paper

“Condensation – Why it Needs to be Addressed in Every Aircraft”

2003-09-08
2003-01-3000
A wide body aircraft carries almost a half–ton of water and ice between the cabin and skin of the aircraft. The water can get on wires and connectors, which can cause electrical problems, cause corrosion and rust, and, eventually, “rain in the plane”. The speaker is the CEO of CTT Systems that has developed a system that solves the condensation by using dry air. The speaker will discuss how condensation can be prevented and how airlines can also save maintenance costs in the process. This topic is relevant for the attendees at the Aerospace Expo, as they are decision makers who need to be aware of this issue. It is also important for the MRO shows as the attendees are on the front lines of dealing with this problem.
Technical Paper

Zero-G Simulation using Neutral Buoyancy

1989-07-01
891529
For human beings who have been reared on the earth with its 1 G gravitational field, the condition of weightlessness is a world with which we are unfamiliar. Even if the layout and equipment configuration of a spacecraft designed to compensate for operation under Zero-G conditions, there are some things which are not effective under actual weightless conditions. In the design of a manned spacecraft, it is necessary to accumulate design data on human performance in a weightless condition, then to undertake design evaluations and verification under weightless conditions. In this paper, testing for the purpose of evaluating the effectiveness of Zero-G simulation using neutral buoyancy, conducted first of all in Japan, and recommendations on the equipment and Facilities required to conduct such simulations, are described.
Technical Paper

XMM - RGS Cryogenic Detector Housing

1994-06-01
941480
The Reflection Grating Spectrometer experiment (RGS) on the ESA corner stone X-Ray Multi-Mirror Mission (XMM) uses charge coupled devices (CCD) as detectors. Thermal requirements are the main driver for the layout of the detector housing. Parasitic heat inputs stem primarily from radiative coupling and from conduction over the structural support. Improvements in the design of the electro optical model (EOM) over the bread board model (BBM) resulted in a system that guarantees a CCD temperature of -130 °C at the end of the mission while not precluding the possibility to heat the detectors as high as +130°C which might be useful for annealing the CCDs.
Technical Paper

XB-70A Laboratory for Progress

1966-02-01
660276
The development of the XB-70 research aircraft produced advancements in many fields of technology. This paper covers a few of these advancements in the areas of materials, equipment, and manufacturing. These include honeycomb construction, PH 15-7 alloy steel, vacuum melted H-11 steel, equipment capable of withstanding high temperatures, chemical milling of many different alloys, miniaturized welding equipment, and exothermic brazing techniques.
Technical Paper

XB-70 Ground Servicing and Safety Precautions

1966-02-01
660275
Planning for ground servicing and maintenance started in the proposal phase and has been followed by test program experience with the XB-70 Mach 3 air vehicle. Servicing and associated safety requirements are summarized. Discussion of maintenance and support actions includes mention of equipment provided to meet the requirements. Preflight, postflight, and periodic operations are outlined, along with some indication of changes that resulted when plans were put into practice. The demands of a high performance flight test air vehicle limit movements toward simplification.
Technical Paper

X-Ray Rocking Curve Analysis of the Aging and Deformation Characteristics in the Al-Li Alloy

1989-04-01
891057
A non-destructive x-ray technique, the double crystal diffractometer method, is presented as a tool to investigate the aging and deformation behavior of the Al-Li alloy. This is a sensitive method for measuring the strain and dislocation density within individual grains through the x-ray rocking curve. In addition, models were developed to describe the aging and deformation characteristics of this alloy.
Technical Paper

X-Ray - A Necessary Tool for Detecting Incipient Structural Failures in Service Aircraft

1964-01-01
640510
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.
Technical Paper

Workload and Situation Awareness in Future Aircraft

1987-10-01
871803
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.
Technical Paper

Working Activity in Space: Preparation of the Scientific Experiments' Performance

2005-07-11
2005-01-2957
One of the most unsolved problems in space projects, where human beings are involved, is the impossibility of simulating on the ground the effects of microgravity on astronauts' operability in space. [1] In particular, this is traceable in the performance of work activities, such as performing physiological scientific experiments. [2] This paper focuses on a study of the gap between the two operational scenarios: the ground test simulation and the in-flight space performance of complex physiological experiments. The major differences between the two operational scenarios are highlighted, and recommendations for improvement are suggested. The main finding of this paper is that, in order to make experiment performance not only possible but also easy and efficient, it is necessary to consider all human factors involved. With this perspective, the author's aim has been to find an effective way to consider all human factors of the ground and space operational conditions.
Technical Paper

Work Measurement Videotaping Technique as a Means for Estimating Food Preparation Labor Time of a Bioregenerative Diet

1999-07-12
1999-01-2075
A bioregenerative diet is characterized by a high proportion of foods produced on site. The production and processing of foods into either ingredients or recipes entails certain labor requirements. Ideally these labor requirements should be estimated with a high degree of accuracy. Crew time is at premium and any amount of time spent on food preparation and processing is time not spent in conducting research and any other activities devised to improve the quality of life of the astronauts. Moreover, a wide variety of tasks are involved in the food preparation of a bioregenerative diet and the labor times of these tasks do not scale or increase in uniform fashion. Predicting food preparation labor requirements for varying crew sizes will require task specific models and data. Videotape analysis is a work measurement tool used in the manufacturing industry.
Technical Paper

Wing/Ground Ice Detection System for Aircraft

1994-02-01
940116
The ability to accurately and reliably annunciate the presence of aircraft wing contaminants greatly reduces the hazards of aircraft operation in winter precipitation environments. A new wing contamination detection system was designed to detect contaminants on the surface of an aircraft wing. Testing on a Fokker F100 aircraft was completed during the 1992-1993 winter icing season. The testing revealed that the system was able to detect ice, frost, hoar frost, and deicing fluid mixtures on the wing. The system performance was evaluated against Fokker's current requirements for an operational system.
Technical Paper

Wing Structural Assembly Methodology

1998-09-15
982156
This paper reviews today's aircraft wing production assembly methodology and technologies as well as innovative ideas for advancing the high-level wing assembly state-of-the-art. Automated wing assembly systems are only being utilized to rivet/fasten first level subassemblies like panels, spars, and ribs. All other high level assembly tasks are performed manually, incurring associated increases in recurring costs due to production inefficiencies, long lead times, expensive rate tooling, and difficult assembly tasks performed inside small wing compartments. Existing assembly methods, process parameters, and the process characteristics of manual, machine, and man/machine systems provide many opportunities for improving wing assembly.
Technical Paper

Wind Gusts - 0 - 300 ft Altitude - Homogeneous Terrain

1970-02-01
700342
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.
Technical Paper

Wide Temperature Magnetization Characteristics of Transverse Magnetically Annealed Amorphous Tapes for High Frequency Aerospace Magnetics

1999-08-02
1999-01-2541
100 kHz magnetization properties of sample transverse magnetically annealed, cobalt-based amorphous and iron-based nanocrystalline tape wound magnetic cores are presented over the temperature range of −150 C to 150 C, at selected values of Bpeak. Frequency resolved characteristics are given over the range of 50 kHz to 1 MHz, but at Bpeak =0.1 T and 50 C only. Basic exciting winding current and induced voltage data were taken on bare toroidal cores, in a standard type measurement setup. A linear permeability model, which represents the core by a parallel L-R circuit, is used to interpret and present the magnetization characteristics and several figures of merit applicable to inductor materials are reviewed.. The 100 kHz permeability thus derived decreases with increasing temperature for the Fe-based, nanocrystalline material, but increases roughly linearly with temperature for the two Co-based materials, as long as Bpeak is sufficiently low to avoid saturation effects.
Technical Paper

Wide Temperature Core Loss Characteristics of Transverse Magnetically Annealed Amorphous Tapes for High Frequency Aerospace Magnetics

1999-08-02
1999-01-2542
100 kHz core loss properties of sample transverse magnetically annealed, cobalt-based amorphous and iron-based nanocrystalline tape wound magnetic cores are presented over the temperature range of -150 C to 150 C, at selected values of Bpeak. For B-fields not close to saturation, the core loss is not sensitive to temperature in this range and is as low as seen in the best MnZn power ferrites at their optimum temperatures. Frequency resolved characteristics are given over the range of 50 kHz to 1 MHz, but at Bpeak = 0.1 T and 50 C only. For example, the 100 kHz specific core loss ranged from 50 mW/cm3 to 70 mW/cm3 for the 3 materials, when measured at 0.1 T and 50 C. This very low high frequency core loss, together with near zero saturation magnetostriction and insensitivity to rough handling, makes these amorphous ribbons strong candidates for power magnetics applications in wide temperature aerospace environments
Technical Paper

Wick Characterization by Image Analysis

2001-07-09
2001-01-2238
The microstructure characterization of tubular wicks is discussed using an image analysis method, mercury intrusion porosimetry and Arquimedes method. The central objective of this work is to determine the wide convenience of the image analysis technique for wick characterization. It is demonstrate that the image analysis technique is an appropriate tool to determine correlation function, total porosity and pore size distribution in two-dimensional (2-D) binary images of microstructures. The correlation function is used to simulate the 3-D reconstruction of porous structure. The images were obtained from a set of wick samples made of sintered nickel, through scanning electronic microscopy (SEM). A computer program (Imago) was developed and used in the work. The mercury intrusion porosimetry is also used to provide information about the breakthrough diameter of porous material. Results show porosity of about 60% and effective pore size less than 4 μm.
Technical Paper

Whither All Weather - An Airplane Manufacturer's Point Of View

1975-02-01
750601
Automatic landing has been developed to the point where all the wide-bodied jets have it as basic equipment. The techniques presently employed are generally founded upon the technology of the last two decades - especially with respect to analog computation and gyroscope references. Several new techniques are now available which can substantially improve the autoland systems for the next generation of transport aircraft. These include airborne digital computers, the use of integrated air-data and strapdown airplane motion reference systems, expanded use of automatic system test, and the development and employment of the Microwave Landing System (MLS). These new technology developments promise to provide expanded operational benefits, reduced maintenance, and increased availability over that of contemporary autoland systems.
Technical Paper

Where the Maintenance Money Goes - And What Can Be Done about It

1963-01-01
630397
Aircraft maintenance expense falls into two broad categories: direct and indirect. A review of the composition of these costs points to means for reducing them. The principle improvements discussed are: provision of better tools and training for supervisors and mechanics, improved work scheduling, new maintenance philosophies for determining when work must be done, and better aircraft design for maintenance.
Technical Paper

When Budget Variances Warrant Investigation by Engineering Project Management

1968-02-01
680683
Paper discusses two quantitative decision tools: one based on actual variance and one based on probability of observing such a variance. Both are used in deciding when to explore budget variances. The two methods are: calculation of decision areas based on the cost of investigation and expected savings produced by an investigation: calculation of the variance as a function of both time remaining in schedule and budget remaining. Both methods can be programmed on a computer. Details of the application of either method are presented.
Technical Paper

What is WAT? Wrap Around Test: Maximizing Avionics BIT Utilization to Minimize Flightline Armament System Test Equipment Requirements

1990-09-01
901787
An evolutionary extension of military aircraft Built-In-Test has been developed for armament systems. This extension, Wrap-Around-Test shows promise in replacing conventional support equipment currently used to test aircraft interfaces prior to weapons loading and during system maintenance. Wrap-Around-Test offers the ability to verify weapon system integrity at a reduced cost, improved operational readiness and enhanced ergonomics.
X