Radio Control: Scale
MEASUREMENTS: A letter from a reader in Finland asks for elaboration on methods of taking measurements of full-scale airplanes. We have, in past columns, expounded the virtues of having the prototype available for examination, photos and dimensional data, but then neglected to explain procedures. We made the incorrect assumption that everyone knew the necessary steps. Juhani Sederholm asks specifically for the method of determining exactly the shape of an unknown airfoil, without damaging the surface of an airplane, after permission is granted to make dimensional checks. When the airfoil designation is known, its outlines can be copied from a standard reference source such as our Handbook for Airfoil Sections by M.S. Rice.
Radio Control: Scale
SCALE DOCUMENTATION: Requests for information regarding documentation material continue to arrive in our mailbox. Doubts usually arise in their hearts when competition Sport and Giant Scale modelers are faced with having to supply photos of obscure aircraft, or those that have been neglected in historical information. If a three-view drawing is available, and the drawing shows color data, photos aren't required. When a three-view drawing alone is the complete documentation, it becomes a one-sheet presentation. To supplement this drawing, some modelers will include several additional sheets of printed data about the prototype, not realizing that judges have very little time to do extensive reading.
I985 NATS: RC Scale
ONE WEEK before the start of the Springfield-Chicopee Nats, Dolly departed from Delafield in our stretched van, loaded with hand-painted signs and two models, the Aeronca K and the ancient Piel Beryl. I stayed behind in Wisconsin to attend the EAA annual convention at Oshkosh, where I met Ken Flaglor, builder of the Grand Champion award-winning Gee Bee Y. Ken was planning a flight to the Nats, to exhibit his Gee Bee at the Westover AFB during the last half of Nats week. My departure on Tuesday was an early morning airline flight, directly across Lake Michigan, non-stop to New York. Ken started from a nearby airport at Kenosha, flew around Chicago's O'Hare Airport and the southern tip of the lake, made three stops for fuel, refreshment, and whatever else cross-country pilots need to do, and arrived at Springfield one hour ahead of me. His air time was seven hours. My flight was only two hours, but much time was lost waiting for bus transportation.
Radio Control: Scale
PARIS FAI MEETING: The annual trek to Paris for rules and technical specifications is finished, and we brought back some rather astonishing results. For many years we have heard the lament from U.S. competitors that FAI model specifications were too restrictive, particularly on engine displacements. It was generally agreed that the day of a single .60 two-stroke engine in a Scale model was long since a thing of the past, and yet the FAI rule book persisted in this upper limit. The restraining limit was imposed originally because of the suspected unreliability of earlier radio equipment and because of a general regard for safety in the days when models could be lethal missiles in the hands of novice pilots. Actually, some of these conditions may continue to exist, but it has become increasingly apparent that the old restrictions were somewhat antiquated and were stifling competition.
Radio Control: Scale
SCALE MATH: Scale modelers who build from kits have some of their questions answered by the designer or manufacturer. The expected weight of the model and the suggested range of engine sizes is given on the drawing or instruction booklet. Scratch-builders ask searching questions on such important matters as a projected estimate of model weight and engine requirements, and the answer really is needed in the early stages of design. Once a model size has been decided upon, wingspan and area are a straightforward function of the scale ratio, that number which represents the difference between full-size aircraft and the model. We simply divide the prototype's span by the scale ratio to determine the model's span.
