Focus on Competition
Technically Speaking ...
Greg Hahn Technical Director [email protected]
New products are available for use! The Safety Committee has approved alternate materials for use as control lines for all general, sport, and competition flying. These materials have been in use for other sporting activities—mainly fishing—for several years and the control-line (CL) community has been interested in using them, but needed the Safety Committee’s endorsement to put them to use. Much of the testing was demonstrated firsthand for the committee at its annual meeting at the Toledo Expo in Toledo, Ohio, this year by Tom Hampshire. This ultimately led to the approval for use.
The CL Combat group has already voted in the use of the new lines in the past cycle and inclusion in its rule book had been waiting for the Safety Committee’s approval. It will be interesting to see how many of the other CL groups adopt the use of the new lines.
Authorized wording from the Safety Committee
"Lines made of Spectra fiber, made of gel-spun ultra-high molecular-weight polyethylene (GSUMP) are permitted for sport flying and demonstration purposes. Spectra lines are not permitted in competition unless the specific rules for the event flown expressly permit such use. The use of high-visibility yellow lines is recommended, but not required. For sport and demonstration flying with two lines, Spectra lines shall have the following strengths:
- Aircraft weight not over 24 oz.; Engine displacement less than 0.09 cu.in; Electric less than 300 watts; Rated Spectra strength: 20 lbs., .010" dia.
- Aircraft weight not over 40 oz.; Engine displacement less than 0.25 cu.in; Electric less than 450 watts; Rated Spectra strength: 40 lbs., .013" dia.
- Aircraft weight not over 64 oz.; Engine displacement less than 0.40 cu.in; Electric less than 600 watts; Rated Spectra strength: 60 lbs., .016" dia.
- Aircraft weight not over 75 oz.; Engine displacement less than 0.75 cu.in; Electric less than 750 watts; Rated Spectra strength: 100 lbs., .018" dia.
All lines shall be pull-tested to 10 times the model weight. An aircraft must meet both the weight and power standards to qualify for the stated line size. Exceeding either standard places the aircraft in the next larger line-size bracket. Aircraft shall be weighed with either a full fuel tank or battery on board.
Terminations shall be constructed using a 5-turn uni knot, tied on a bight, or two strands of line looped back from the free end. An instruction film of the knot can be found at www.youtube.com/watch?v=cGL2JD9q-cE. The drawings below show a single strand for clarity, but should be tied on a bight. The knot is tied as follows:"
- Run at least six inches of line through the eye of the clip, and fold to make two parallel lines. Bring the tag end of the line back in a circle toward the clip.
- Make six turns with the tag end around the double line and through the circle.
- Hold the double line at the point where it passes through the eye, and pull the tag end to snug up the turns.
- To create a loop connection: adjust the loop size by sliding the knot up or down the standing line. Then pull the tag end with pliers to maximize tightness.
- To create a snug knot: pull the standing line to slide the knot up against the eye. Then continue pulling until the knot is tight. Trim the tag end flush with the closest coil on the knot.
Be safe and have fun. MA
Transcribed from original scans by AI. Minor OCR errors may remain.
