Spherical Parachute Patterns

These patterns can be used to create hemisphere parachutes for model rockets or egg drops. Instructions for constructing the parachutes can be found in the May/June 2000 newsletter of the Northern Illinois Rocketry Association.

The article describes the construction of 12 inch diameter parachute with 8 gores and a 2 inch diameter spill hole. This web page will produce patterns for other sizes of parachutes.

My daughter used this pattern to create a 16 inch diameter hemisphere parachute with a 1 inch spill hole for an egg drop in her eighth grade science class. Her egg was one of two that survived a 30 foot drop.

A hemisphere parachute has twice the drag of a comparable sized parasheet style parachute made from a flat sheet of plastic. A spill hole will reduce the drag of the parachute, but will cause a more stable descent.

The length of the parachute shroud lines should be 1 1/2 times the diameter of the parachute.

Patterns include a 1/4 inch seam allowance.

Please check your print settings before printing the pattern. Acrobat Reader will resize an oversized pattern to fit the page by default. If your pattern is larger than your page, you may have to select a larger paper size, and/or create your parachute with more gores.

So what size parachute do you need? Let's find out.

Weight of payload in ounces:    

Create a Parachute Pattern

Parachute Diameter in inches

Percent of Sphere

50% will produce a hemisphere parachute. 25% will produce a half-hemisphere parachute.

Number of Gores

Spill Hole Diameter in Inches

Paper Size in Inches

     x    (at least 8 x 8, not more than 120 x 120)