Free Flight Sport
Gene Smith [[email protected]]
Twiggy turns 30?
Clarence Mather's Twiggy design was published in MA 30 years ago this month. The model's name was inspired by a popular fashion model of the era. Neither the airplane nor the fashion model had any curves, but both did their jobs well!
Clarence still uses Twiggy to show kids how to build and fly model airplanes. He does this in conjunction with his local 4-H organization.
The original Twiggy had tissue covering on both sides of all flying surfaces, but now Clarence covers only the top of the wing and stabilizer and one side of the fin to speed building. A unique design feature is that the right wing is longer than the left; this induces a right turn.
If you don't have any Tan Super Sport, loop three #33 rubber bands together and go flying. These rubber bands are approximately $3 for a 1-pound bag at your nearest office-supply store.
Check out the Twiggy in the MA digital archives; it was published in the July 1976 issue. If you don't have Internet access, send me an SASE for a free copy of the plans. You can get the propeller and bearing from Peck-Polymers or Penn Valley Hobbies.
While checking out the D.C. Maxecuters club Web site (www.his.com/~tschmitt/005HOMEPAGE/MAXECUTER.HTML/) I saw a picture of a beautifully finished Comet Dime Scale model built from a Penn Valley Hobbies Lockheed Vega kit. It was crafted by David Mitchell.
David built the Vega according to the plans except that he added a few stringers to enhance the scale appearance. He covered the model with white and blue Esaki tissue to match the scheme used on Wiley Post's Vega.
Flying opportunities have been limited, but initial flights looked good. Times have been in the 45- to 55-second range, which was good enough for second place in the model's first contest. Without rubber the Winnie Mae weighs 13.8 grams and is flying with a single braided loop of 1/8-inch rubber weighing 4.7 grams. The current flying propeller is a 6-inch Sleek Streak, but David plans to replace it with a better-looking option. See Penn Valley Hobbies' ad in this magazine, and be sure to check out the Maxecuters' Web site.
From the darkest recesses of Snider Swamp comes Return of the Bounty Hunter. No, it's not another sequel to a bad western; it's the latest iteration of Dick Mathis's contest-winning FF design from the 1960s. For several years Bill Vanderbeek has sponsored a one-design 1/2A Gas event that is held at several contests during the flying season, including the AMA Nats. Past designs have been the Space Rod, the Starduster X, the T-Bird, and the Fubar. This year's design is Bill Chenault's Mini Pearl.
Larry Kruse knew Dick Mathis in the 1960s. I was familiar with Dick's designs, having built his Trigger when I was a kid. Larry and I were mulling over possible models for the one-design event and wondered if one of Dick's designs would work. We checked with Bill, and he was receptive to the idea of using a Mathis design for the one-design event in 2007, so we started narrowing down the prospects.
Dick had been out of the modeling scene for more than 30 years, but Larry managed to locate him and rekindle his interest in free flight. Dick identified most with his Bounty Hunter design.
The bad news was that when the Bounty Hunter was designed, large models and long engine runs were the rule. At 418 square inches, the Bounty Hunter was too large for the short engine runs flown in today’s Category III contests. The good news was that Dick was willing to reduce the model to 240 square inches for the one-design event.
Larry and I built prototypes from Dick’s new plans. The Bounty Hunter has his trademark geodetic construction technique, which results in extremely strong flying surfaces. I had planned on a tissue-and-dope finish, but the wing and stabilizer frames were so stiff that I elected to use UltraCote Lite.
A Bounty Hunter 240 construction article is tentatively scheduled to be published in the September MA. Kits will be available late this year or early next year, so you can have your version ready for the 2007 Nats.
The one-design event is flown according to Nostalgia Gas rules. Any Nostalgia Gas engine is legal. Models such as the Bounty Hunter, which are not Nostalgia-legal, may also use a Tee Dee .049 or .051.
Glenn Bearry has been using a unique blast tube for more than 10 years. It does not require a long winding wire. The tube has a slit its entire length. The motor is inserted by rotating the propeller shaft 90° to the motor, placing the shaft in the slot, and sliding it up the slit in the tube with the propeller and nose block on the outside and the hook with motor attached on the inside. Once the motor has been wound, reverse the process.
Cutting the tubing takes effort and practice. Press with a razor blade or utility knife, lift, then press again. The tubing is tough, but it's soft enough to slice with effort. The tube's strength is decreased when it is slit, so it will bulge with a broken motor but will contain it.
Glenn has broken motors as large as 12 strands of 1/8-inch rubber without damaging the airframe. He is convinced that anyone who tries the blast tube will like it. The benefits are quicker winding and the fact that one does not have to transfer the slippery motor from a winding wire to the propeller hook.
George White has made several of these blast tubes and has been happy with them. He found 5/8- and 3/4-inch-diameter material in 20-foot lengths at a plumbing-supply firm. The 3/8-inch-diameter material was found at a mobile-home supplier where it was sold by the foot; it is used for water-supply lines.
George White built a nifty Dime Scale Mauboussin Hemiptere Type 40 from plans by Al Backstrom. The model caught air on an early test flight and recorded a respectable 95 seconds.
George started with the CG at the wing spar, approximately 30% of the wing chord. He flies the model to the right and uses 3° right thrust and 3° downthrust. The left wing has a bit less than 1/16 inch of washout, and the right wing is flat. Empty weight is 17.5 grams. Power is a 20-inch loop of 1/8-inch rubber and a 20-inch loop of 1/16-inch rubber.
I hope you have your Dakota ready for this year’s event at the Nats. I flew mine last year and had a blast. Once things get underway, Dakotas buzz all around. It’s a good idea to stay alert and upwind! The goal is a target time, so you have a chance of scoring if you can get your model into the air. Come join the fun.
Earlier this year Jim Moseley distributed results, a report, and photos of the 2005 KK Senator Postal contest to contestants and donors. The event had entrants from many countries and carried awards totaling approximately $370.
This year’s postal contest began February 1 and will close January 31, 2007. The time span allows summer participation from fliers in both hemispheres. This event already has donations and pledges equivalent to the total awards for 2005.
Jim expects a larger number of modelers to record scores this year. To encourage more participation there is also a team challenge. Individuals who have no modelers in their area can even form a team with those who live elsewhere.
Jim uses a 30-gram motor, six strands of 1/4-inch rubber, turning a 13 x 19 propeller on his model. Some have built the Senator as light as 55 grams, but most average 60. It’s important to keep the airplane light aft of the wing to minimize nose ballast. Jim winds to torque but says the 30-gram motor will typically take more than 1,000 turns. That makes a two-minute flight routine.
The Senator is a simple, strong design that performs beyond its original expectations. Vintage-legal in the United Kingdom and elsewhere, it also serves well in US Category III events such as Nostalgia Rubber, Moffett, and even Mulvihill.
Plans are available at www.theplanpage.com/st.htm. If you do not have a computer, Jim can help with full-size plans. Anyone who is interested in the details of this year’s event should contact Jim at [email protected] or:
Jim Moseley 19 Banner Cres. Ajax, Ontario L1S 3S8 Canada
We are fortunate to have a new kit vendor: Rocky Top Models. The kits feature Mike Midkiff’s CAD plans, laser-cut parts, covering material, documentation, colored plain-paper insignia, propeller, and propeller hardware.
The first two kits are:
- 18-inch-span S.E.5a — $24.95 plus shipping and handling
- 29-inch-span Miles Magister — $42.95 plus shipping and handling
Visit www.rockytopmodels.com or contact Mike at (817) 845-4189.
If you need Nostalgia or Society of Antique Modelers engine rework, Don Blackburn has a new mailing address:
Box 954 Perkins, OK 74059 Telephone: (405) 547-1219
Transcribed from original scans by AI. Minor OCR errors may remain.
