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Q. Where does one find statistics on this sport? Are there statistics on canopy malfunctions based on types, manufacturers and mode of usage? Which style of parachute(s) have the most jumps with the fewest problems? Are there statistics available on packing techniques and the resultant problems?
A. Unfortunately, no such statistics exist for our sport. The task of collecting, compiling and analyzing reliable data on the relative safety of different parachutes and different organizations would be a Herculean task for our small sport.
The weakest link in the "safety chain" of modern sport parachuting is the jumper himself, not the equipment. Today's mainstream equipment is quite reliable; some jumpers have thousands of consecutive jumps without any equipment malfunctions.
If you want to do the same, stay away from collapsible pilot chutes (especially those that require cocking), elliptical main canopies, 500-lb. Spectra suspension line, soft cutaway housings, red cutaway cable, round reserves, canopies made entirely of zero-porosity fabric, soft reserve handles, unreinforced mini-ring risers, belly bands, and old automatic openers. Select a rig and main that have been on the market for at least two years.
Used gear is OK, but worn out is not.
Learn how to use your new gear. Read the owner's manuals from cover to cover. Get some instruction. Make a few familiarization jumps -- solo. Stay current.
Learn to pack and avoid using packers. Packing can be fast and easy if you skip all the careful pleating, folding and tucking that has no effect on deployment anyway. Finally, keep your gear in good condition. Inspect it while packing and before every jump. Have a rigger give it a thorough once-over every 200 jumps or so, looking for stuff like worn loops, Velcro and lines. If the main starts to open poorly, send it back to the factory for a trim check.
Having said all this, don't be surprised if, one day, when you least expect it, your canopy opens into a spinning mess. It happens; there are no guarantees. Bowling is safer.
Q. Are there any parachute systems with two reserves?
A. Manufacturers often use such rigs for test jumps, but they're not FAA approved. The incidence of reserve malfunctions is so low that there's little if any demand for such a rig.
Q. Do riggers lose their certificates if a parachute they've packed malfunctions?
A. FAA-certificated riggers are subject to fines and the loss (or suspension) of their certificates for malpractice and for failure to comply with the Federal Aviation Regulations. But each case is different, and parachutes sometimes malfunction even when the rigger does everything right. Enforcement actions against riggers are rare.
Q. Where can I get a computerized cutting table for making parachutes?
A. Computer-driven cutting tables are available from several companies, but these commercial tables were designed for making clothes, sails and signs -- not parachutes.
Bill Coe, president of Performance Designs, engineered and built the two big tables his company uses. They use computer-controlled lasers to cut the fabric. Performance Designs' telephone is 904-738-2224, fax 904-734-8297.
Paul Martyn of New Zealand Aerosports also developed his own software and hardware for designing and making parachutes. At least two U.S. manufacturers, Air Time Designs and Precision Aerodynamics, have purchased his systems. The table cuts the fabric with a hot knife. His company's telephone is 64-9-3600045, fax 64-9-3788571.
Q. Do you know of anyone who uses a communication device in freefall? I'm wondering why miniaturized, inside-the-helmet "walkie talkies" aren't widespread in this sport.
A. Skydive Chicago is uses such a system for student training; see Skydiving magazine issue #190. The DZ's telephone is (815) 433-0000.
Q. I've never jumped but I've been chosen to put together a trip for several co-workers. How do you find the right place, a company that will ensure safety but also make it fun. I've been calling companies listed in the Yellow Pages, but I want to be sure the company is reputable.
A. It's a good idea to visit several area DZs before picking one for your first-jump training. Make your visit when the weather is good, so you can see the DZ in action. Although you might not yet know much about skydiving, you'll nonetheless be able to quickly tell which DZs are right for you and your group.
Q. I read that legstrap hand-deploy pilot chutes are unsafe for freeflying because they're more prone to premature deployment. The author recommended using a bottom-of-container (BOC) pilot chute only.
A. BOC pilot chutes are generally safer for freeflying because they're less prone to snagging since they have little or no exposed bridle. They also might better withstand the higher-speed, omnidirectional airstream that one routinely encounters while freeflying.
A legstrap pilot chute is suitable for freeflying if its pocket it tight (and not too big or stretched out of shape), the Velcro isn't worn out, and the rig is packed correctly and checked before exit.
By the way, these same requirements apply to all types of skydiving not just freeflying. Accidental deployments are obviously dangerous, especially if the jumper is not belly to earth and if other jumpers are above her. Minimizing such malfunctions is a worthwhile goal. A BOC does just that, so it makes sense to take advantage of its benefits.
Q. During an aircraft emergency, what is the lowest altitude at which you can bail out and survive?
A. Tough question about a tough decision. If the aircraft is gliding (and not out of control) and if you pulled your reserve as soon as you left the door, you'd probably make it if you bailed out at 400 or 500 feet above the ground. From a standing start, most ram-air reserves need only a couple hundred feet to open, if the pilot chute works perfectly. If the aircraft is below 1000 feet, a decision to bail out has to made and performed immediately.
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Copyright 1998. 10/01/98.
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