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FUNDAMENTAL REASONS UNDERLYING SAFETY COACH DESIGN
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English
Abstract
The problem in building the first “safety coach” was to short-cut evolution-to bridge the gap between what the industry had and what it needed. It is the purpose in this paper to consider the broad fundamentals and underlying principles of the Fageol safety-coach which have formed the basis of subsequent modern motorcoach construction, giving particulars of detailed design only to point out and illustrate the methods of definitely meeting the known needs.
It was noted that equipment for all types of transportation had undergone a definite evolution, beginning with vehicles designed primarily for some other type of service. The early railroad equipment was adapted from the horse-drawn stagecoach. The first automobiles were literally “horseless carriages.” The first motor-stages were adapted from the touring car or the truck. Either of the latter was good for the purpose it was designed to fulfill-both had great shortcomings in public motor passenger-service.
Taking as a guide the experience of the railroads as sellers of commercial transportation, it was found that the first requisite for the ultimate motorcoach was ability to serve best and attract patronage. The yardstick by which the equipment would succeed or fail would be its ability to sell rides, and the requirements for this passenger popularity were safety, comfort, convenience features, and dependability, coupled with operating economy. The passenger automobile has fixed not only the riding habits of the public but the rate of acceleration and speed up-hill or on the level. Any vehicle that does not closely approximate these conditions must ultimately fail in the transportation field and become a menace to traffic.
Since all the available commercial engines were designed for either low-speed trucking or relatively lightweight passenger-car service, it became necessary to design a new engine that contained the characteristics of enormous torque at low speeds and power enough for 45 to 50-m.p.h. service, with practically no vibration at any speed. The design of this engine was intrusted to E. J. Hall.
For the chassis of the coach it was necessary to reduce the floor height, lower the center of gravity and spread the wheels apart so that it would not only be actually but obviously safe. Bodies for city and interurban service were designed with a view to comfort and convenience and were constructed to take-up torsion due to uneven road surfaces without damage to the body.
Many refinements have been made during the last 4 years, but the main fundamentals of construction, developed through investigation before starting to build, have not been deviated from, and the early conclusions of the designers seem to be confirmed by the almost unanimous adoption of the main features of design as the standards of the industry.