A parachute fabric is specifically designed for parachutes. Due to its high strength and longevity, a parachute fabric is immensely used in parachutes. Parachutes were once made from silk but now they are almost always constructed from more durable woven nylon fabric, sometimes coated with a - silicone - zero porosity coating to improve performance and consistency over time.
Parachute fabric has been ruling the parachute world for long time and no competitor appears to be displacing it form the top spot in near future. Parachutes are made with great prudence using parachute fabrics that are in tune with various new technologies. As manufactured to suit the requirement of most discerning people, the parachute fabric capable of impressing anyone
Fabric for canopy
Suggested material is lightweight ripstop nylon. For the prototype parachute that I constructed, I simply used a nylon shower curtain, which was nearly ideal, the only drawbacks being it was not ripstop and that it was somewhat heavier fabric than was necessary. It had a nice tight weave, not surprisingly, since it's intended purpose dictates that it be water-resistant! The following table lists the specifications for commercial parachute fabrics, as well as for the fabric that I used for the prototype parachute:
Parachute Fabric Properties
WARP FILL THICKNESS TEARING BREAK AIR
MIL WEIGHT COUNT COUNT STRENGTH STRENGTH PERMEABILITY
CODE TYPE (oz/sq.yd.) (per in.) (per in.) (in) (lbs) (lbs/in) (CFM/sq.ft)
498E D 0.88 90 90 N.A. 2.5 40 300-500
498E G 0.88 90 90 N.A. 2.5 40 100-325
7020H I 1.10 120 120 0.003 5.0 42 80-120
7020H II 1.60 120 120 0.004 5.0 50 100-160
44378 I 1.17 126 132 0.003 5.0 45 0-5
* * 1.81 80 100 0.004 N.A. 47 N.A.
* IKEAtm, Billingen shower curtain (white) or Rosanna (off-white), 180x200 cm.; p/n 17763 (Billigen), 14331 (Rosanna), $14.50 CAD (sufficient fabric to make two 1-metre diameter canopies). Fabric for both is identical (100% nylon). The latter has a water-repellant coating, but this can be eliminated (before dyeing) by washing the fabric in hot water with laundry detergent. Properties listed for this fabric were determined by measurement and/or testing.
One half of the quantity of fabric that was used to make the canopy was dyed red. The dye used was:
• RIT tm, tint & dye, #5 scarlet, one 32 gram package, $1.77 CAD.
Cord for shroud lines
The type that I used was braided nylon cord, the kind that is sold in the camping department of stores. The specific type that I used was:
• World Famoustm, p/n 3150, 15 m. package, $2.47 CAD.
The approximate width and thickness of the cord, measured under light tension loading, are :
• width = 0.175 in. (4.5 mm)
• thickness = 0.050 in. (1.27 mm)
and the cord tested breaking strength is:
• Breaking strength = 185 lbs (822 N.) average
The thread that was used for machine stitching the canopy together and for sewing the shroud lines to the canopy was the following:
• Coats tm, 100% nylon upholstery thread, 137 m. spool, $2.79 CAD
The measured diameter, and tested breaking strength of the thread are:
• Diameter = 0.013 in. (0.33 mm)
• Breaking strength = 9 lb. (40 N.) average
The seam binding that was used to join the canopy panels was as follows:
• Wrights tm, Iron On Hem Tape, 100% polyester, PC22, 2.75 m. package, $1.97 CAD
which is identical to the
• Wrights tm, "Soft and Easy" Seam binding, 100% polyester, PC16, 2.75 m. package, $1.97 CAD
except that the hem tape has heat activated adhesive to facilitate the joining process.
The measured dimensions and tested breaking strength are:
• width = 0.525 in. (13 mm)
• thickness = 0.005 in. (0.13 mm)
• Breaking strength (longitudinal) = 61 lbs (271 N.) average
• Breaking strength (transverse) = 46 lbs/in (81 N/cm.) minimum