Radio Control: Scale
ON-BOARD IGNITION. A high percentage of Scale models need weight, added in the nose, to counterbalance a tail-heavy condition. Don't feel bad about having to add nose weight-it's needed on some full-size aircraft, too. The DC-4 had about three-quarters of a ton of ballast in its nose. Nevertheless, adding weight to an already-burdened Scale model always seems like a gross waste. A convenient (and useful) five-oz. nose weight is a 4 amp Ni-Cd D-cell that can be used for on-board glow ignition. Reliable engine idling and positive throttle response under all conditions are benefits of using the cell. All D-cells are not alike. The common, inexpensive variety found in electronic retail stores is much lighter, is rated at 1 1/4 amps, and is really a C-cell in a D case. Most glow plugs will draw three amps, which results in a very short useful life between charges if the 1 1/4-amp D or C cell is used in place of the four-amp cell. We use the GE 1.25V, 4 Ah, model HD 1000.
Radio Control: Scale
MANEUVERABILITY. We have been asked whether our semi-aerobatic Scale models will do a Lomcevak, and the answer is "No," of course. In order to do these and other violent maneuvers, a model requires an excess amount of control surface travel. There isn't any question that the model's controls could be set up for extreme aerobatics, but this would inevitably result in a super-sensitive airplane in which tiny movements of the transmitter controls would alter the flight path visibly. Scale flight illusion would be destroyed, even under the guidance of an expert pilot.
Radio Control: Scale
NEW RC FREQUENCIES. At a recent local RC meeting, our District VII Frequency Coordinator, Pete Waters, was present with his charts of our area, showing the location of industrial transmitters that posed a threat to flying RC models. It was disclosed that a local telephone company had built a transmitter on one of the commonly-used RC frequencies, 75.64 MHz, a few miles distant from our club flying field. Without Pete's help, we would have gone on using 75.64 until someone was shot down. Even the loss of a trainer built in a few weeks is lamentable, but the model could also have been a Scale type, with 2,000 hours of building time.
Radio Control: Scale
REPORT FROM PARIS. A drastic change has been made in the FAI RC and CL Scale rules, as the result of a vote at last December's CIAM meeting, to scuttle Precision Scale, which had become a victim of a worldwide decline in participation. Stand-off Scale becomes the only international RC and CL event after January 1984. The change will reduce static judging time considerably, as there will be no measurements taken (the scale ruler has been eliminated). Our current AMA rule book stipulates that RC Precision Scale is to use the FAI rules, except for higher weight limit and greater engine displacement. This means that we will now have two kinds of Stand-off Scale rules in our book. Actually, the only reason to perpetuate AMA Precision Scale is to have a basis for team selection, since there are so few contests that include the event. Selecting a team now becomes a problem, particularly if there is to be a series of eliminations leading to a final event. FAI rules would need to be used throughout the process to assure sending qualified airplanes and pilots to the next World Championship (in France for 1984, and to Norway of South Africa for 1986).
Radio Control: Scale
FOAM-CUTTER CONTROL. Our June 1983 column contained a photo showing a control box for hot-wire foam cutting. Letters were received inquiring about the contents of the box, and whether it was a purchased item or homemade. The control was asembled here in our workshop, using standard components purchased from local suppliers. The aluminum enclosure is a standard electrical components box 4 in. × 5 in. × 6 in. from a radio parts supply store. Inside are two transformers. The first is a Powerstat variable autotransformer which is the product of Superior Electric Co. of Bristol, CT. It is a type 10B with a 120-volt input and a variable 0-to-120-volt output. It isn't safe to use its output directly on the hot wire because of the shock hazard. (Its output is not isolated from the house power lines.) Touching any metal parts of the foam cutter could be hazardous when standing on a concrete floor or touching a grounded object. Any current flow of 5 mA or greater, through the human body, contracts muscles, and the person is unable to release his grip. This may be lethal, if the heart is affected.
