Control Line: Aerobatics
Wynn Paul
FOAM PRODUCTS UPDATE: Control Specialties Co. has some new twists on the foam wing that stunt fliers should like. First off, entrepreneur Bob Hunt now offers foam flaps which have been cut out as an integral part of the total airfoil. In other words, wing and flap are cut from the same piece of foam in one cut, then separated and covered with a balsa skin. There is a balsa insert in the flap to receive the flap horn. Most "46"-size wings and flaps are covered with 3/64-in. balsa; "35"s are covered with 1/32-in. balsa. All that is needed to attach the flaps is to cut a 45-degree bevel on the flap, sand off the sharp edge on the trailing edge of the wing and put in the hinges. The writer has one of these wings for his new Pampawagon IV and the work exceeds even the other great wings from C.S.C.
A second innovation with the CSC wing is the inclusion of two built-in 1/8-in. lite-ply half ribs placed to accept landing gear blocks. The blocks are glued into a recess cut into the bottom of the wing. The two half ribs on each side are cut out and an estimate of their weight would be 3.0 grams each. The weight of the landing gear blocks (also manufactured by CSC at $4.95) is 15.5 grams each. The weight of each landing gear wire (1/8-in. stock) is 15.0 grams. This means that you can have the complete landing gear assembly minus wheels and spats weighing in at 73 grams or about 2 1/2 oz., which is not bad. And, the gear is removable in case you bend it wrong or have a hard landing.
And lastly, CSC is now offering foam stabilizers and elevators covered with balsa skins. Bob offers two standard designs, the Genesis 46 size (3-1/2-in. root with 2-1/2-in. tip) and the Genesis 35 size (3-in. root and 2-in. tip). Both of these designs are 1/2 inch thick at the center section. He can make up a stab-elevator design to your own specifications. The "46" sizes are covered with 3/64-in. skins and the "35" sizes are covered with 1/32-in. balsa. The stabilizer is strong enough to withstand hard corners; there is a 1/8-in. plywood spar imbedded in the foam at the trailing edge of the stab that extends six inches on either side of the center. There is a piece of balsa imbedded in the elevators to receive the elevator horn and give a solid mounting. All stabs and elevators are made up in spans to suit the customer's desires. Prices vary and interested fliers should contact Bob at 205 Wood Ave., P.O. Box 268, Middlesex, NJ 08846; telephone 210-469-1663. Bob advises that stabs should have a gauze strip epoxied around the center as with the wings for rigidity.
More than one stunt flier has observed the abundance of top caliber competitors in stunt in the past couple of years. It could probably be said that any one of a dozen fliers could win the Nationals nowadays. The writer feels that the rapid development and acceptance of the foam-wing airplane has been a deciding factor in this emergence of a multitude of very good stunt fliers. While some may argue that a foam wing is not as light as its built-up counterpart there are many who will dispute this, among them Gene Schaffer and Bob Hunt, both noted for very light airplanes. Bob states that he uses "Cello-foam expanded polystyrene" that has a weight of one pound per cubic foot. He says that a "46"-size wing cored out, just the foam, weighs approximately 3/4 ounce! The weight comes from the balsa and the glue. He has switched recently to Wilhold spray cement which he considers to be lighter and more efficient. Incidentally, the 35-size wing cored weighs about 1/4 ounce.
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CL Aerobatics/Paul continued from page 40
Despite any concern with weight the two biggest factors on the plus side of foam wings is the fact that they are usually very straight and possess a constant and even airfoil at all points. These two factors should be enough to make a plane fly well. Both Bob Hunt of CSC, and Arnold Stott of Foam Flite have developed the "popcorn wings" to a craftsmanship which is outstanding and the results are being seen in the standings of contests and the Nationals as more and more foam wings show up with the winners.
Nationals Format Change: PAMPA President Keith Trostle is currently reviewing several proposals to change the format of the precision aerobatics event at the Nationals in 1977. There are three items which have received a lot of talk, well all right, griping if you must, about stunt at the Nats: (1) a need for open stunt contestants to have more official flights in the qualifications process — in the past several years many contestants have only been able to put up one flight in the whole stunt event at the Nats; (2) the National Champion should be decided by more than one official flight; (3) the Walker Cup flyoff could be a more representative award if a slightly altered program for the flyoffs was adopted; this would call for from 5 to 10 "finalists" to participate, including the Junior and Senior champions, with each contestant performing three official flights.
The 1977 Nats may see two days of open stunt qualifications with two official flights each day. Qualifiers would be chosen by adding the best score from each day. After picking 15 to 20 qualifiers for a "semi-finals" or "Walker Cup Eliminations" the top 5 to 10 would advance to the Walker Cup flyoff. Comments on this should be sent to Keith Trostle, 10900 Phillips Dr., Upper Marlboro, MD 20770.
Special Stunt Products: There are several specialized products for stunt which are not usually on your local hobby dealer's shelves. Here are a few.
"The Muffler," produced by Bob Paul (no kin to the writer) and used successfully by Bob Gieseke and Bill Werwage. A picture of this muffler appeared in the December, 1976 issue of Model Aviation, page 25. Weighing in at a competitive one ounce, this muffler is hand-built by Bob for any engine and has no parts which can come loose and fall off the engine. Bob can build it for use with or without muffler pressure. This muffler has a minimum of back pressure and is not bulky looking on the airplane. Cost is $21.50 including postage and handling. Bob also is now offering engine work on most popular stunt engines. Contact him at 4428 W. 49th St., Cleveland, OH 44144.
Leadout Cable: Rolland and Bob McDonald report that they have for sale .040-diameter nylon-coated steel leadout cable at 15¢ per foot. This is an extremely tough cable which will not fray or wear in the bellcrank. Contact them at 28746 Westfield, Livonia, MI 48150.
Engines and Engine Rework: Carlos Aloise, more famous for his championship carrier planes than for stunt, is now offering a stunt version of the Cox TD .049 or .051, a special 5.8-oz. 40 stunt engine, and a special 9.2-oz. 60 stunt engine. These engines are especially made up by Carlos and he states that they are easy starting, very powerful, and have low fuel consumption. He also states that he will rework most any commercial engine to your specifications. Send for his catalog of services offered: 2314 Loy Lane, Los Angeles, CA 90041; telephone: 213 254-9795.
Bisco Bender: Harry Higley, also of carrier fame, is manufacturing a very useful tubing bender which can be used to shape hard brass tubing as well as soft tube. Can be used for fuel tank pickups and vents, needle valve extensions and other miscellaneous plumbing. Price is $1.25 and the address is 433 Arquilla Dr., Glenwood, IL 60425.
For information about PAMPA, or anything else contact the writer.
Wynn Paul, 1640 Maywick Dr., Lexington, KY 40504.
Transcribed from original scans by AI. Minor OCR errors may remain.
