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Owing to the inadequacy of conventional laboratory windshield qualification testing methods, it is not unusual for unforeseen problems to develop in the real world of flight service. Aircraft windshields are normally subjected to static, material, environmental, and, in some instances, to limited service condition testing before being incorporated into prototype hardware. In‐service monitoring is used to compare the prototype to previous designs. Determining the relative effectiveness of corrective “fixes” or design improvements by in‐service testing can take months or even years of calendar time. To overcome these prob‐lems, Sierracin has developed and constructed an advanced Windshield Flight Environment Simulator (WFES), that duplicates the total operating environment of electrically‐heated, pressurized windshields, on a highly compressed time scale.

A previous article by Hansrobert Kohler, presenting a mathematical method for calculating the optical characteristics of cone‐shaped cockpit windshields, was published in the June issue.

Since this paper was first published additional work has been carried out which, though not affecting the stated conclusions contained in the information herein, has brought about additional beneficial results and knowledge. Consequently, a second article will follow as a sequel to that now published.

THE National Advisory Committee for Aeronautics is conducting a programme of research intended to reduce the risks now attendant on aeroplane operation during icing conditions. A part of this programme is concerned with the prevention of ice on the windshield. The methods investigated involve the use of: (1) heat from an electric source, (2) heat from the engine exhaust, and (3) an alcohol‐dispensing, rotating wiper‐blade. Inasmuch as the problem of ice prevention exists in several forms, it is anticipated that several different methods may find application on the aeroplane. The obstructions of vision through a windshield may result from ice or snow formations on the exterior surface or from the formation of frost on the interior. The object of the present investigation, therefore, was to determine the extent to which the several methods could preserve vision. Observations were also made to determine the capacity of the rotating wiper‐blade to remove rain from the windshield.

The purpose of this paper is to identify the appropriate method, demonstrating with a prototype model, of how knowledge in reliability management can be elicited from individuals as well as a team.

The approach is to elicit the tacit knowledge of the reliability engineers through narratives and cognitive mapping. With a sufficient number of cognitive maps, patterns are revealed and an aggregate cognitive map for all participating members is produced, which helps to summarize various approaches and procedures that can be taken in handling different reliability management issues.

The work provides a real‐life example to support the stages of learning from the individual, the group to the organizational level as described in the theoretical Learning Framework.

Many knowledge management programs failed for various reasons. One common pitfall is that they are either too ambitious or too vague in the scope, methodology of their deliverables. To be successful, the project objectives should be linked to the business needs that lead to solving their business problems.

A prototype is developed in the organization of expertise knowledge in a bottom‐up manner in the building of a corporate memory from individuals to team level in the reliability management in an airline company.

This is the first study in the airline industry to capture the know‐how and experience of its reliability engineers in the form of congregate cognitive maps so as to facilitate team learning and the building of organizational memory. It is the first in the airline industry to adopt this methodology for developing its own procedure manuals. The model was implemented successfully in the Engineering Division of an airline business in order to handle their reliability management issues.

The main purpose of this paper is to gain a better understanding of the transient aerodynamic characteristics of moving windshield wipers. In addition, this paper also strives to illustrate and clarify how the wiper motion impacts the airflow structure; the aerodynamic interaction of two wipers is also discussed.

A standard vehicle model proposed by the Motor Industry Research Association and a pair of simplified bone wipers are introduced, and a dynamic mesh technique and user-defined functions are used to achieve the wiper motion. Finite volume methods and large eddy simulation (LES) are used to simulate the transient airflow field. The simulation results are validated through the wind tunnel test.

The results obtained from the study are presented graphically, and pressure, velocity distributions, airflow structures, aerodynamic drag and lift force are shown. Significant influences of wiper motion on airflow structures are achieved. The maximum value of aerodynamic lift and drag force exists when wipers are rotating and there is a certain change rule. The aerodynamic lift and drag force when wipers are rotating downward is greater than when wipers are rotating upward, and the force when rotating upward is greater than that when steady. The aerodynamic lift and drag forces of the driver-side wiper is greater than those of the passenger-side wiper.

The LES method in combination with dynamic mesh technique to study the transient aerodynamic characteristics of windshield wipers is relatively new.

Just looking through a car's windshield does not give us much reason to wonder about how it is made. The idea that special manufacturing expertise might be required can hardly occur to anyone, but that is exactly what is needed to ensure crystal‐clear visibility, not to mention a perfect fit every time one is pressed into place on a car production line. Comprising two thin glass sheets joined by a vinyl interlayer, windshields are assembled – usually manually – to a very precise product and environmental specifications. To make sure this is done as perfectly as possible, the industry invests heavily in the equipment used for their fabrication. ABB has now developed a robot‐based Compact Assembling System for the automatic assembly of laminated windshields that speeds up production and increases cost efficiency.

This paper describes the results of a study on new configurations for the windshield and the canopy of the M346, a new military trainer aircraft with two staggered seats, currently in phase of construction at Aermacchi (Venegono Superiore, Italy). The study carried out demonstrated that forward rotation allows a reduction of the weight of the structure, improves the visual field of the pilots and moreover, allows a greater accessibility to the panel instrumentation. Obviously, all the related aspects have been considered in the development of the study, such as the opening/closure, latching/unlatching and locking systems of the canopy, the tightness for pressurisation, tightness for water and dust also when the aircraft is parked, the resistance to bird impact, the forces due to wind when the canopy is opened on the ground and, in the case of emergency, the systems to break the transparent material and to eject the pilots.