A Quick and Easy Launch Chute
Tom Gist
A launch chute for RC sailplanes not only helps spot where the tow-hook end of the tow line comes down, but it also floats back the tow hook toward the launching area. This chute goes together quickly.
There have been several articles over the years on making chutes for sailplane launching. Most described chutes that were sewn together from many curved panels, just like full-size parachutes. After trying to sew together one of these flexible jigsaw puzzles, I decided there must be at least one easier way. This article describes the one I use now.
Materials and equipment
- Two pieces of fabric, 12 x 4 in. each (polyester or nylon sailcloth is ideal)
- Four pieces of shroud line, about 36 in. each (braided or twisted; monofilament will not do)
- Two tow rings (a heavier ring at the bottom is helpful)
- Sewing machine capable of zigzag stitch (a machine that can do darning or smocking stitches is best, but plain zigzag will work)
Notes:
- I used rip-stop nylon from a hot-air balloon maker; sailmaking shops are another source.
- Since each of the four shroud lines is sewn and then doubled through the rings, there are actually eight shroud line segments. The line material does not have to be super strong; if it has about 25% of the strength of the main launch line, there will be a two-to-one margin.
Assembly
- Lay the two pieces of fabric on one another in a cross (as in the drawing) and pin them together.
- Starting at the corner of one piece, run a zigzag stitch all the way around that piece and back to the same corner. The pieces should be joined by two seams. Repeat the process on the other piece, then remove the pins.
- Make sure the outside edge of the zigzag is right at the fabric edge or slightly off the edge to keep the fabric from raveling. The four seams around the center square lock the two pieces together.
- Lay one of the shroud lines across the chute diagonally from one corner to the opposite corner, with the center of the line at the center of the chute. Thread a tow ring onto the line.
- Using the darning or zigzag stitch, sew the line to the fabric along its length, keeping the tow ring in the center. Try to keep the line from twisting as you sew and keep a little tension on it so it lies flat.
- Sew the second line diagonally across the center in the opposite direction.
- Sew the remaining two shroud lines about 1-1/2 in. from the edge, running parallel to the outside seam.
- Pass the loose shroud line ends through the tow ring and tie, making sure the knot equalizes the lengths so the lines share the strain equally.
- Stretch all the lines tight from the tow ring, thread them through the other ring, and tie an overhand knot through the second ring. Make sure all lines are equally taut under tow.
You're ready to use the chute.
Final comments
- It helps to use a heavier ring at the bottom of the chute. If the top ring is too heavy, it pulls the chute down and prevents it from opening.
- Note that the lines are on the outside of the chute canopy.
- I prefer a rather small chute so the tow line comes down quickly. It's easy to change the size to suit your needs; just make sure the pieces of fabric are at least three times as long as they are wide. If not, the canopy loses stability and tends to collapse.
Transcribed from original scans by AI. Minor OCR errors may remain.
