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Pivot point concepts for fighter type aircraft with variable sweep wings are reviewed. Structural and aerodynamic considerations involved in sweep pivot location, a summary of endurance testing of Teflon lined journal bearings, and variation of fatigue life of the aircraft versus wing sweep position are discussed.

Effects which normally diminish the value of a manually flown instrument approach are examined in the light of flight test results with the Head-Up Display (HUD). It is possible to avoid shortsightedness (space myopia) and disorientation phenomena associated with poor external visibility, by choice of display position and format, allowing an efficient alternation between display and forward view. The display can also be designed to fit the man, in both static and dynamic characteristics, with benefits of rapid learning and accurate tracking. These results remove the basis for supposing man's intervention in the all-weather landing to be disastrous. On the other hand, man's participation may be necessary, because more information is connected with a safe approach than can be dealt with by an unaided machine. Synthesis of an automatic system with HUD may turn out to be the most acceptable solution to the overall problem of all-weather operation.

The F/A-18 has the capability to perform a greater variety of fighter/attack missions than any other single-place aircraft ever produced. This paper will not address any new discussion of the “one vs. two” crewmember situation, but only present the human factors engineering history that produced the current man-machine interface in the F/A-18. The extensive software capability of the airplane has made changes found desirable during flight test reasonably easy to incorporate into production aircraft. These changes encompass everything from aircraft handling qualities and display formats (heads-down and heads-up) to radar and weapons system operation. Previous aircraft have depended, in varying degrees, on the unique capabilities of the pilot to compensate for inherent crew station/weapon system deficiencies.

The U.S. Air Force has recognized the need for an alternative to the conventional hydraulic brake system. Hazards associated with fires and the maintenance required for a hydraulically actuated system are the principal drawbacks of hydraulic brake systems. In addition, an alternative brake system will be required to support a “More Electric” aircraft of the future. The solution to these problems was provided by the “Electrically Actuated Brake Technology (ELABRAT)” program, a three year program sponsored by the Flight Dynamics Directorate at Wright Patterson AFB. ELABRAT developed and demonstrated an Electromechanically Actuated (EMA) brake system to replace the existing hydraulically actuated piston housing and associated hydraulic control hardware.

Aircraft designs have been characterized by an increasing utilization of variable geometry features as aircraft capabilities expand into new flight regimes. The trend seems likely to continue as requirements for new aircraft become continually more demanding. The successful application of variable geometry depends on several things: the understanding of the aerodynamic principles involved, efficient structure, and whether an overall worthwhile improvementin performance, maneuverability, or flying qualities is gained; since it certainly will cost more, be less reliable, and more difficult to maintain. The application of some existing and proposed variable geometry schemes to aircraft is discussed. The aerodynamic factors affecting low and high speed performance, maneuverability, and stability and control characteristics indicate some of the desirable and troublesome aspects of these concepts.