RE: Sig Shoestring/Norvel 15
54 ft. lines? Sure it is not 52.5 ft? At 52.5 ft, 8 laps = 1/2 mile. That's what Goodyear used to be back in the 70's, and what is used in various Sportsman-type Goodyear classes around the country. Limited (= ST G15) Goodyear in the upper Midwest switched over to 60' when the Goodyear rules changed. Don't think it is flown anymore.
Jim