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Technical Paper

Human Centered Manufacturing: a Necessity for Enhancing Productivity and Competitiveness

1999-04-20
1999-01-1605
This paper argues in favor of a human-centered (anthropocentric) approach to modern manufacturing. The bases for these arguments are: (a) worker deskilling and creativity issues, (b) economics, and (c) unresolved problems in automation, such as software reliance and costs. Detailed arguments are avoided owing to space limitations. Finally, some issues confronting human-centered manufacturing are raised.
Technical Paper

The Lean and Agile Manufacturing Model

1999-04-20
1999-01-1611
The Lean and Agile Manufacturing Simulation Model simulates the concepts of lean and agile manufacturing. A “live” working factory model is used to contrast the operating styles between a typical “mass production” plant and a “lean” production plant. Participants work as a team to plan, fabricate, manufacture, assemble, and ship two types of products using three common manufacturing processes - Traditional Mass Production (Push), Just-In-Time Manufacturing (Pull), and Cellular Manufacturing (Cell). Model functions include; warehousing, fabrication, WIP storage, assembly, inspection, accounting and shipping utilizing a miniature factory model, complete with tools, fixtures, materials and shop floor paperwork transactions. The model initially utilizes a traditional Material Requirements Planning (MRP) based scheduling approach to operate the factory.
Technical Paper

Is There a Need for Human Factors and Error Management in General and Corporate Aviation?

1999-04-20
1999-01-1595
This paper explores the need for human factors and error management within the context of the general and corporate aviation environments. It discusses strategies currently employed in other segments of the aviation industry and how they might be utilized in the corporate and general aviation arenas. It also relates research findings and program successes experienced within the airline industry and makes recommendations as to how a consortial effort by industry organizations might be utilized to employ these strategies in corporate and general aviation operations.
Technical Paper

Corporate Aviation on the Leading Edge: Systemic Implementation of Macro-human Factors in Aviation Maintenance

1999-04-20
1999-01-1596
While majority of the airlines are struggling to implement macro human factors principles in their maintenance activities, at least eleven corporate aviation departments (CADs) in the country are showing signs of success. The implementation philosophy of these CADs differs from others, and from the airlines in one fundamental aspect: it enforces a behavior change rather than an attitude change among the CAD employees. Consequently, they strive to achieve an employee behavior which is consistent within and across their flight operations, maintenance, and management functions. Ethnographic research was conducted at one of the eleven eligible sites to develop a theoretical model which is representative of the structure, the strategy, and the processes used by these aviation departments to implement macro human factors principles in aviation maintenance. This model was then tested at three other CADs that have a implemented similar approach.
Technical Paper

SJ30-2 High Performance Business Jet Development: A Prototype Based Approach

1999-04-20
1999-01-1593
The SJ30-2 is a high performance, entry level business jet with the design goal of offering performance superior to other aircraft in its class. Critical data were obtained and evaluated early in the development program through flight and structural testing of a prototype aircraft. Prototype testing helped to achieve aggressive design goals and minimized potential design changes for the globally located manufacturing team. This prototype based approach reduced the program schedule risk in the production and certification phase.
Technical Paper

Application of Shape Memory Alloys for Leading Edge Deicing

1999-04-20
1999-01-1585
Ice accumulation on aircraft wings during flight is a dangerous situation. To deal with this problem, current deicing systems either prevent ice accumulation by heating or break the ice layer once it is formed by dynamic motion of a leading edge device such as a boot. These systems may be deficient due to excessive energy requirements or ineffectiveness. In this project, the feasibility of using shape memory alloy (SMA) composite material for deicing purposes is investigated. SMA such as Nitinol wire has an unusual characteristic where it can be trained to generate a compressive strain upon application of an electric current through the wire. Several different versions of two inch radius semi-circular SMA composite specimen were manufactured and tested at Wichita State University. Ice was successfully shed in static icing tests while each of the subsequent versions reduced the power input requirement.
Technical Paper

Analysis Tools for DaDTA on Riveted Lap Joints

1999-04-20
1999-01-1587
Two specific concerns that could affect safety limits for aging aircraft are the effects of corrosion damage and widespread fatigue damage (WFD) on structural integrity. A common joint in fuselage structure is the riveted lap joint, which overlaps two fuselage skin panels. This design creates complex loading conditions that require various analysis methods for accomplishing a durability and damage tolerance (DaDT) analysis. Under an Air Force research project, Boeing evaluated the capabilities of several advanced analysis tools for assessing the effects of corrosion and WFD on the structural integrity of riveted lap joints.
Technical Paper

Analysis of Widespread Fatigue Damage in Lap Joints

1999-04-20
1999-01-1586
This paper describes research to analyze widespread fatigue damage in lap joints. The particular objective is to determine when large numbers of small cracks could degrade the joint strength to an unacceptable level. A deterministic model is described to compute fatigue crack growth and residual strength of riveted panels that contain multiple cracks. Fatigue crack growth tests conducted to evaluate the predictive model are summarized, and indicate good agreement between experimental and numerical results. Monte Carlo simulations are then performed to determine the influence of statistical variability on various analysis parameters.
Technical Paper

An Automated System for Drill Bit Verification

1999-04-20
1999-01-1565
Aerospace manufactures purchase millions of drill bits each year for the manufacture of large aircraft structures. This paper describes an ongoing research project for the development of an automated system to detect poor quality drill bits before they are put to use.
Technical Paper

Evaluation of Chip-Tool Interface Conditions using Transparent Tools

1999-04-20
1999-01-1563
In-situ high speed photographic observations through transparent ceramic cutting tools have been used to observe the dynamic contact interactions at the chip-tool interface while cutting commercially pure copper under a range of cutting speeds and rake angles. Under all conditions it is observed that the chip slides over the rake surface of the tool close to the cutting edge. Under low cutting speeds some chip material is transferred to the tool where the chip curls out of contact with the tool in the form of a fairly thick deposit. At higher cutting speeds a fine layer of chip material is transferred to the tool closer to the cutting edge and the thick deposits formed at lower speed are removed. The tendency for deposition is decreased as the rake angle is decreased. In all cases the dynamic nature of the cutting process and the slow evolution of the deposition are clearly evident.
Technical Paper

Hole Quality Study in High Speed Drilling of Composite and Aluminum Sheet Metal

1999-04-20
1999-01-1564
Drilling is one of the most widely applied manufacturing operations. Millions of holes are drilled today in manufacturing industries especially in aerospace industry where high quality holes are essential. Rejection and rework rate of the products because of the bad hole is quite high. In this research graphite/honeycomb composite material and aluminum sheet metal has been used. The results show that drill geometry, speed and feed rate have substantial effects on the hole quality and also there was gradual variation of the thrust and lateral forces with feed rates.
Technical Paper

Multistage Sheet Metal Forming with Intermediate Annealing: Comparison of Finite Element Simulations with Experiments

1999-04-20
1999-01-1560
This paper describes a methodology to simulate multistage sheet metal forming with intermediate heat treatments and its application to the three stage forming of an engine nacelle inlet lip. This capability has been validated by comparing results of finite element simulations for plastic strains at various points in the sheet with values obtained experimentally using the strain circle technique.
Technical Paper

Mathematical Models of Fastened Structural Connections

1999-04-20
1999-01-1576
The development of efficient and reliable methods for the design and analysis of fastened structural connections is among the most important problems in aerospace applications because fastened structural connections are common sites of failure initiation. Numerical simulation of fastened structural connections is difficult because there are complicated interactions between the fasteners and the structural components being joined and one of the most important attributes of a fastened connection, the clearance, is a stochastic variable. This paper presents a mathematical model for frictionless shear connections and its implementation within the framework of the p-version of the finite element method.
Technical Paper

Activities of the Federal Aviation Administration’s Aviation Weather Research Program

1999-04-20
1999-01-1578
Weather is a major cause of aircraft accidents and incidents and the single largest contributor to air traffic system delays. Through improvements in the knowledge of current weather conditions and reliable forecasts, the Federal Aviation Administration (FAA) can improve aviation safety, increase system capacity, and enhance flight planning and fuel efficiency. The FAA has established an Aviation Weather Research (AWR) program to address specific requirements for weather support to aviation by providing the capability to generate more accurate and accessible weather observations, warnings, and forecasts and also by increasing the scientific understanding of atmospheric processes that spawn aviation weather hazards. The goal of AWR is to provide meteorological research that leads to the satisfaction of specific aviation weather requirements.
Technical Paper

A New Apparatus to Evaluate Lubricants for Space Applications - The Spiral Orbit Tribometer (SOT)

2000-06-19
2000-01-1828
Lubricants used in space mechanisms must be thoroughly tested prior to their selection for critical applications. Traditionally, two types of tests have been used: accelerated and full-scale. Accelerated tests are rapid, economical, and provide useful information for gross screening of candidate lubricants. Although full-scale tests are more believable because they mimic actual spacecraft conditions, they are expensive and time consuming. The spiral orbit tribometer compromises between the two extremes. It rapidly determines the rate of tribochemically induced lubricant consumption, which leads to finite test times, under realistic rolling/pivoting conditions that occur in angular contact bearings.
Technical Paper

Beech AT-10 Wichita

2000-05-09
2000-01-1679
This paper describes the design and development of the Beech AT-10 multi-engine pilot transitional trainer. It also covers the use of the AT-10 as a research aircraft.
Technical Paper

Spin Resistance Development for Small Airplanes - A Retrospective

2000-05-09
2000-01-1691
With the resurgence of the General Aviation industry, the incentive to develop new airplanes for the low-end market has increased. Increased production of small airplanes provides the designers and manufacturers the opportunity to incorporate advanced technologies that are not readily retrofitable to existing designs. Spin resistance is one such technology whose development was concluded by NASA during the 1980’s when the production of small airplanes had slipped into near extinction. This paper reviews the development of spin resistance technology for small airplanes with emphasis on wing design. The definition of what constitutes spin resistance and the resulting amendment of the Federal Aviation Regulations Part 23 to enable certification of spin resistant airplanes are also covered.
Technical Paper

Design and Test of an Improved Crashworthiness Small Composite Airframe

2000-05-09
2000-01-1673
The goals of this NASA Phase II SBIR program were to develop design methodology to improve occupant survivability in small composite airplanes. Current technology small airplanes absorb crash energy primarily in the cabin structure. The current study tried to increase strength of the occupant compartment and design energy absorbing structure outside the passenger compartment. Dynamics of the crash event were analyzed using a PC version of DYNA3D. Four full scale tests in two crash scenarios were conducted at the NASA Impact Dynamics Test Facility with test parameters set to allow direct comparison with prior NASA/FAA tests. Results indicate that occupant survivability can be improved with moderate weight penalty.
Technical Paper

Eco-labels and Eco-Indices. Do They Make Sense?

2000-04-26
2000-01-1473
Life Cycle Assessments (LCA) of complex systems, such as vehicles and vehicle components, are based on the quantification of the energy, wastes, and emissions associated with the material production, manufacturing, use and end of life of the product. However, the volume of information needed to provide a comprehensive assessment of the environmental burdens is large and complicates the decision process in choosing among alternatives. For this reason people have attempted to simplify the information by collapsing it into a single index, which essentially assigns a score to a product of being “good” or “bad”. Even though such an approach looks attractive to the decision-makers that want simple answers based on meaningful data, the results may be misleading.
Technical Paper

Life Cycle Simulation as R&D Tool

2000-04-26
2000-01-1500
Life-Cycle Simulation (LCS) is an inventory modeling approach to replace the “snap-shot” character of life-cycle inventories. Requirements of Life Cycle R&D tools and possibilities of LCS will be discussed. The goal of Life Cycle Simulation is holistic optimization of products and technologies, i.e. technical performance, economic efficiency and ecoefficiency. Worldwide applied automotive painting concepts and new painting strategies have been investigated with the LCS approach. Significant economic and environmental optimization potentials have been identified which meet the high technical performance requirements of the automotive painting process.
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