Radio Control: Scale
LANDING GEAR LOCATION. A letter from a reader raised the question of the effect on ground handling, takeoff and landing, when wheel centers are displaced forward or aft from optimum location. Experience tells us that, when wheels are too far forward, there is sometimes a tendency for a model to ground loop, that is, to divert from a straight path on takeoff or landing, with the result that a wing tip will touch the ground. The worst condition encountered in this situation could be an alternate scraping of both wing tips, with the model eventually going over on its back. This can lead to a messy repair, particularly for a biplane. Airplanes most susceptible to ground looping are those with tail skids and wheels far ahead of the center-of-gravity.
Radio Control: Scale
FOUR-STROKE ENGINES: While visiting England last summer, we were introduced to new (to us) Laser four-stroke engines. Two engines were single-cylinder, valve-in-head types of .61 and .75 cu. in. displacement. Most interesting from the Scale modeler's viewpoint was the Laser 1.20 twin, a V-type with two carburetors. These are all bar-stock engines with no castings. The twin has an extremely low idle speed and showed no hesitation on acceleration. Fuel is 20% castor oil, and no nitro is needed. Special glow plugs aren't required. British modelers are understandably enthused about their new four-stroke engines.
Radio Control: Scale
DETAIL ANALYSIS: On the pretext that the model is to be Stand-off Scale, the external detail is kept to as little as will be accepted by fellow modelers. If the airplane being modeled is a later, jet type (a Boeing B-47 for example), external detail presents no burdensome task for the modeler because it's relatively clean on the outside. A Douglas DC-3 has a pair of magnificent wing-root fillets, non-existent on a B-47, and a model without the fillets wouldn't be a DC-3. In addition, the Douglas has several hundred thousand button-head rivets cluttering every surface. Duplicating the large quantity of rivet detail constitutes a major commitment in time and energy. Opinions on the amount of detail to be applied vary, depending upon the builder's purpose and aspirations.
Radio Control: Scale
FIBERGLASS over foam: An engine cowl, with its compound curves and continuously changing shape, is the airplane part that lends itself to fiberglass-over-foam construction methods. Blue styrene insulation foam is used because it is easily cut and formed. It has a more rigid cell structure than the white foam ordinarily used for wing cores. It can be sawed to rough shape with a hand, band, or circular saw. (The circular saw can be somewhat hazardous, because the fast-moving blade can melt the foam, which causes it to seize the blade violently. The sudden action can pull the operator's hand into the blade.) The least troublesome method of cutting foam is with the electrically-heated nichrome wire. Look for Styrofoam under "Insulation Materials" in the Yellow Pages, to find a local supplier.
Aeronca K
THE 1937 AERONCA K was an airplane commonly used for low cost flight training, at a time when the 40-hp J-3 Piper Cub was its competitor. The Aeronca was also a favorite of the new breed of sportsman pilot who wanted the joy of flight without all the expense attached to the maintenance of large airplanes and their fuel-hungry radial engines. The K was the first of the Aeroncas to have the appearance of a cabin airplane, and it represented a break from the traditional Aeronca bathtub style C-2 and C-3 that were its predecessors. Only the two-cylinder Aeronca-built engine and the wing dimensions were carried over from earlier production, although the horsepower was increased from 36 to 40. The distinctive sound of its engine couldn't be mistaken for that of any other aircraft.
