Maximum Seat Research Articles

On the optimum cruise speed of a hypersonic aircraft

Some preliminary results that have been obtained in the frame of the SANGER system studies are presented. SANGER is a West German study project and technology reference system for a future advanced space transportation system. The first stage of this vehicle is a hypersonic aircraft from which a passenger version could be derived. The analyses indicate that a speed of Mach 4.4 will lead to maximum seat mileage per day as well as to minimum propellant consumption. The speed-related cruise altitude of 24500 m or 80000 ft is above the most sensitive ozone layer and high enough to produce only one-third of the noise ground pressure which is considered as the acceptable limit (1 lb/ft/sup 2/) over populated areas. The aircraft surface temperatures at these conditions can still be managed by a conventional titanium alloy structure with special provisions only at the leading edge and the engine inlets. The potential route structure and economics of such an aircraft are discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

A biodynamic basis for perceived categories of action: a study of sitting and stair climbing.

Actors must determine whether the properties of the surface layout are sufficient to meet their specific requirements for performing an action. Warren's (1984) study of bipedal stair climbing has demonstrated the significance of intrinsic, body-scaled measures of environmental properties for defining perceptual categories relevant to action. Whereas the absolute measure of the perceptual boundary between "climbable" and "not climbable" varied according to the actor's size and mass, the perceived boundary was a constant proportion of each actor's leg length. Our current study examined the perceived maximum seat height (SHmax) for the act of sitting. Experiment 1 delineated the range of surface heights that were perceived to afford sitting on. When expressed as a function of each person's leg length (L), SHmax was remarkably stable across individuals. Unexpectedly, it was quite close to the maximum riser height determined by Warren. Experiment 2 examined whether this similarity reflected a common biodynamic requirement, since climbing and sitting require actors to lift their center of gravity above the surface of support. Perceived critical heights were obtained for both acts using the same methods and apparatus. The perceived maximum heights for each act were virtually identical. These findings are consistent with the possibility that the information used in determining critical action boundaries is already scaled with reference to some physical dimension of the actor.

Acoustics of the enclosed stadium for the University of Idaho, Moscow ID

The enclosed stadium for the University of Idaho, known as the Kibbie-ASUI Activity Center was the recipient of a 1976 American Society of Civil Engineers award for engineering excellence. This unique structure, with a maximum seating capacity of 21 000 is one of the few recently completed enclosed multipurpose stadium structures. The acoustical characteristics of this building will be illustrated and discussed with particular emphasis on the special engineering and operational problems of enclosing such large spaces. [Architects/Engineers: Cline Smull Hamill Associates, Boise, Idaho. The authors were principal consultants for this project while employed at Bolt Beranek and Newman, Inc.]