Acro Star - RC sports biplane model. For .40 or .60 power.
Quote: - "We tried to capture the essential appearance of the EAA bipe, using moment arms and proportions that have provided good flying characteristics on other biplane designs we have flown. This design is not scale but most of our friends who have seen it thought it was. By changing the headrest outline and interplane struts you can create a Smith Miniplane, or several other similar homebuilt aircraft. One of the nice things about homebuilt aircraft is that they are as individualistic as modelers, and modifications of the basic design are many and varied. This model packs 820 square inches of lifting surface into a compact sized ship that, when fully assembled, easily fits into the back of a Pinto Station Wagon. Prototypes have been flown with engines from .40 to .60 size, and weights between 5-1/2 and 7 pounds. The prototype shown in the photos is powered by a Veco .61 with muffler and weighs 6.5 pounds with an Orbit 4 channel radio system and PS-6 servos. With 5.7 square feet of area this works out to a wing loading of 18 ounces/sq ft. Powered with a good .40, such as the OS Max or K&B FR .40, the Acro-Star is a great sport ship for the Sunday flier. With a .60 up front it will fly the pattern and execute the vertical maneuvers with ease. Our prototype is dressed up with optional features such as the inter-plane 'N' struts, wheel pants, cabane fairings, pilot, etc. These add to the looks but the simpler basic version shown on the plans flies just as well. The widespread use of electric starters ensure easy starting with the inverted engine shown. If you prefer an upright engine, just turn it over and cut a hole in the top cowl block and raise the tank slightly higher. Structural design is conventional, with a few innovations to help make the job easier. Wing construction is almost the same for both wings, and both are easily built on a flat surface without special jigs. The lower wing has a slight amount of dihedral to prevent a 'drooped tip' appearance, and the ailerons are cut out and hinged after the assembly is completed for easy alignment. The spruce spars and full span shear webs provide quick building and a very strong warp-resistant structure. Medium weight 3/32 sheeting ensures smooth covering and provides a little extra material for sanding, with only a slight increase in weight. The solid tail surfaces are easy to assemble and finish, and angling the grain as shown provides warp resistance..."
Article pages, text and pics (incomplete), thanks to hlsat. Also, article part 2 (remaining pages) thanks to ar196.
Did we get something wrong with this plan? That happens sometimes. Help us make a correction
* 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, 2011-2017.
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.