Control Line: Aerobatics
Wynn Paul
THE MODEL AIRPLANE industry production is at an all time high in number and quality of products. However, there are some items which stunt flyers would welcome and would make the production of the competition airplane somewhat easier. The writer hopes that some manufacturers will consider these items.
First and most significant is the need for larger fuel tanks. Presently stunters can buy good 3-, 3.5- and 4-ounce tanks. However, with the meteoric rise in the use of the 40 and 46 engines there is a definite need for 4¼-, 5-, 5¼- and 5½-ounce tanks — at least a 5¼-ounce tank if only one would be made. The tanks should be two inches wide, and one inch in height, similar to the old Veco (now Clary) tanks. The fuel pickup tube should exit from the right side of the tank (looking from a top view) with the centerline being one-half inch from the bottom of the tank.
The fuel vents should probably be similar to the old Veco tank since these would work in stock configuration and the "Pros" would modify them to their tastes anyway. Presently there are three fuel systems in use: the old suction method, uni-flo, and uni-flo with muffler pressure. Manufacturers could set up a tank with the two vent tubes in the lower lefthand corner of the left side of the tank, as per the illustration:
BAFFLE
BIND TUBING WITH BRASS WIRE AND SOLDER
This type of venting has been used successfully by several stunt flyers over a period of years. Some may disagree on the routing of the tubes but basically the thing stunters need is the tank itself. A baffle should be on the inside of the tank as shown in the diagram.
The next specialty item needed is a flap horn that is adjustable. Present horns are getting better as they are coming with bearings (either brass or springs), but we need a horn that is adjustable in moment length. This would require a screw type adjustment similar to some RC hardware. Along with this, stunters need a heavy duty Kwik-Link type clevis connection that we can trust. The standard clevises just can't stand the demands of the stunt machine; many crashes have resulted from clevis failure.
How about an adjustable handle with thumb-screw type adjustments similar to the Bob Baron - Bob Hunt - Gene Schaffer - Bill Simons type handle in use for several years. This would probably come out to be a $20 item, but would be worth it for minute adjustments in line separation and lengths.
CL Aerobatics
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It seems hard enough right now to find three-in. nylon bellcranks, at least in the Kentucky area, but how about a 3½-in. bellcrank. This would allow a less sensitive control setup with more leverage.
Adjustable leadouts are standard items on most stunt planes now. How about a ready-made item that gives a travel of at least two inches. Lew McFarland has used the Pylon item, but split it end to end and used a press-in piece of tubing for more adjustment.
A number of flyers would like to use the solid lines if they could obtain them without buying a reel of 1,000 ft. The writer was told by the local hobby shop that solid lines are in the catalog but seldom available.
Finally, sooner or later someone is going to come up with a set of retract gear that comes in at better than five ounces. When this happens there will be a large stampede to the model shop and there will probably be 500 sets sold the first year. Maybe even carrier would be able to use them. The greatest hindrance for using them now is the weight problem; solve this and some manufacturer will have a winner.
Transcribed from original scans by AI. Minor OCR errors may remain.
