I tried using the surgical tubing in cold weather. It doesn't retain any elasticity when it gets close to freezing. I went with 3/8 inch woven bungee 30 ft long, stretched to total of 45-48 ft, with 20-23 lbs tension, based on a fish scale I bought at walmart for 5 bucks. (I am using the JePe dolly with wheels. On my first launch the hook was too tight on the dolly bar, and the horizontal part of the hook was too long, so it didn't release. I cut it down to 1/4 inch past the bend, and extended the length to the fuselage, and have had no problems since.)