The Next Step - Bigger is Better

Once you have mastered the basics of control line flying, it is better to go a little bigger.  A larger model will not get you as dizzy and will be much more stable during level flight.

The SIG Akromaster or Flight Streak Jr. is a good model for today's modern .15 engine, like an OS15FP.   If you want to get into a bit larger, go with the SIG Skyray 35.  See the "Brett Buck's Starter Package" configuration below.  The Ringmaster is a good nostalgic flyer but current production quality of the kits are not so good.  I would rather build a Carl Goldberg "Shoestring Stunter" or "Buster"  if you can find it. Most of these early kits were designed originally for a Fox .35, can easily be powered by today's modern .20 or .25.

Unfortunately, the OSFP .20 for Control Line is no longer made.  You can currently order the OS 25 LA CL series from Towerhobbies. If you have a modern OS 20 or 25 that was designed for R/C you can convert it to C/L.  Even if you leave it as an R/C engine, it still works well for C/L.  All you have to do is to tighten the throttle position opened.   Today's engine will turn a higher RPM than engines of the past. Therefore, you need to go to a lower pitch propeller on these engine, so don't use the old standard 10 X 6. Try an APC 9 X 4 or 10 X 4 propeller at about 11-12K RPM. Also, Brodak has a new .25 engine that works well in this application.

If you want to get into flaps, the SIG Twister is a good model. Many pilots  in the beginner ranks have advanced using a modified version of the SIG Twister known as a "Fancherize Twister". This was a version made famous by Ted Fancher in a 1985 AMA article.  The major result of the modification was to extend the tail moment 2 to 3 inch. giving the airplane a better turning characteristics in corners.  For a bit larger engine such as .35 to .40 engine, the SIG Banshee is a great flyer if you shorten the nose about 1 to 1 1/2 inches. I think this is a much better flyer that on Twister, however most people complain about its appearance.

Brett Buck's Skyray

V.P. PAMPA district X
Brett Buck, PAMPA V.P. of District X and who ranks 3rd at the 2000 nationals, has been entering local contest and scoring in the low 500's, with his OS20FP powered Skyray.

Tips on Building the Sig Skyray 35

I use regular yellow wood glue like Elmers or Tite-Bond and "Quick Grips" by Vise Grips to clamp down doublers for creating a secure sandwich. Pre-glue the surface by putting a thin surface of glue on both side and let is dry for 10 mins then apply another coat before clamping down. Always clamp with a set of blocks to insure even pressure. Let dry overnight.


You need a flat surface to work on. The Sig Skyray can be built on a piece of glass. Just use masking tape and wax paper over the plans. Also, the wing does not require any jig. The supports are built into the rib, so be careful not to cut them off until the wing is complete.

The secret is to attach all of the ribs to the bottom spar first and do not glue it down. I glue the leading edge first by gluing the ends and then supporting center ribs.

I modify a set of clothes pins by contouring the inside to conform to the trailing edge. This make an inexpensive set of clamps.

The bell-crank system is one of the most important components. Make sure that the controls movements are free from friction and securely glued to the spar.