Twelve. Control line sports model. For Fox .29 power. November 1954, Model Airplane News.
Quote: "Evolved from a long series of designs, this .29 to .35 powered stunter is popular in the San Francisco area. A winner, it is a cinch to build. The Twelve, by Jack Rittner.
This is the twelfth model in a series of stunt and combat models. It is especially suited for Fox, Torpedo and Veco engines of .29 to .35 cu. in. displacement. Although this model is extremely maneuverable, it is so easy to fly that many fellows in San Francisco have learned to fly the entire AMA stunt pattern with a Twelve.
This airplane is capable of doing large and round, or small, square-cornered maneuvers, with ease. it has been completely debugged during the two years of its life, and is capable of winning contests. Twelve's contest-winning ability is well displayed by my success with the design during the 1953 contest season, wherein my Twelve won or placed second in every contest entered under Western Associated Modelers' sanction. This record resulted in a place for me on the 1953 Northern California Plymouth Team.
In building, use a good grade of lacquer cement on all parts or you will end up with a silk bag of loose parts after a few flights, as Twelve flies 90 mph on 60-ft, .012 lines with Fox .29 and 9 x 7 prop. Cement motor mounts to fuselage sides; let dry; cement firewall to motor mounts and sides; install gas tank.
Build wing in normal manner: the three center ribs are shown dotted. Plank center bottom, install bellcrank and push-rod, plank top center. Cement fuselage sides to leading edge, pull tail end together and cement, add tails (use hardest 1/8 sheet for stabilizer you can find), and add fuselage formers and the three 1/8 square stringers. Install landing gear, bottom sheeting, bolt engine in and install top nose block. Sandpaper the entire structure, double cement every joint, and cover the entire model with silk. Apply three coats of clear nitrate dope, two coats of clear butyrate, and two thin coats of colored, butyrate trim. The finished model should weigh between 18 and 24 oz.
Your Twelve, if properly built, will reward you with many hours of trouble-free operation, for it is not easily ruined. Practice is the keynote to winning stunt contests, so try to wear out your Twelve. I have a Twelve with at least 11 gallons of fuel run through it which is working on its third engine and still going strong.
Fill the fuel tank through either vent. When fuel runs out the other vent with the model in a normal position, the tank is full. For best results, plug the vent on the outside of the circle, after filling, with a wood screw and a piece of neoprene tubing. This tank will run exactly as you set it on the ground."
Update 24/10/2018: added article, thanks to RFJ.
Did we get something wrong with this plan? That happens sometimes. Help us make a correction
Do you have a photo you'd like to submit for this page? Then email firstname.lastname@example.org
* Credit field
The Credit field in the Outerzone database is designed to recognise and credit the hard work done in scanning and digitally cleaning these vintage and old timer model aircraft plans to get them into a usable format. Currently, it is also used to credit people simply for uploading the plan to a forum on the internet. Which is not quite the same thing. This will change soon. Probably.
This model plan (like all plans on Outerzone) is supposedly scaled correctly and supposedly will print out nicely at the right size. But that doesn't always happen. If you are about to start building a model plane using this free plan, you are strongly advised to check the scaling very, very carefully before cutting any balsa wood.
© Outerzone, 2011-2019.
All content is free to download for personal use.
For non-personal use and/or publication: plans, photos, excerpts, links etc may be used, provided that full and clear credit is given to Outerzone with appropriate and specific direction to the original content i.e. a direct hyperlink back to the Outerzone source page.
Unauthorized use and/or duplication of this material without express and written permission from this site's owner is strictly prohibited. If we discover that content is being stolen, we will consider filing a formal DMCA notice.