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Beginner CRW

by Jan Meyer

Based on a conversation with Ed Cummings, Eastern Conference Director, First BOD member to perform 1000 CRW jumps.

How do you go about doing your first CRW jump? First you must learn about canopy relative work. You must actively solicit information and proper instruction. Who you find to teach you is almost like playing roulette. There are no "official" USPA rated CRW-masters. The local CRW-god may have survived hundreds or even thousands of CRW jumps, but may be very dangerous to a new CRW jumper or a very poor teacher. Then again, he could be very safe with all CRW jumpers and an excellent teacher. How many RW and CRW jumps does your CRW instructor have? This may or may not indicate an adequate teacher. Check out the credentials of your CRW instructor. Ask the regular jumpers about this jumper. Does he have any other ratings? Does the local USPA instructional staff endorse the CRW teachings of this jumper? Does he have USPA CRW awards, CCS, or NCCS? Any reputable CRW instructor will not be offended by such inquiries.

Read as much as you can about CRW, before doing it. The SIM has one short section on CRW and makes rather dry reading. Terry Parsons' book, Canopy Relative Work, is excellent, but certain parts are becoming dated. This article adds some information on some of the many procedures you should know before doing CRW and suggests one way for safely doing your first CRW jump.

Equipment

Canopy relative work requires compatible "fall rates" just like RW. Fall rates for you and your parachute and other jumpers and their parachutes should be about the same. Everyone should have almost the same full flight speed and glide angle. Someone with a flat glide angle won't be able to do CRW well with someone else with a steep glide angle, even if the glide speeds are the same. This means that jumpers and parachutes have to be matched to each other.

You and your canopy make a parachute system. The fall rate of the system is related to wing loading, that is the planform area of your parachute divided by your weight. Everyone on a given CRW jump should have about the same wing loading. You may also want everyone to have almost the same aspect ratio, too. This requirement usually boils down to all 7 cells or all 9 cells on the load. There are some low aspect ratio 9 cell parachutes that could fly well in a stack of 7 cell parachutes.

Everyone's parachute should have uncascaded A lines in the center cell and color coded if possible. A cross connector should be installed from the front to the rear riser on each side. Improperly installed cross connectors (front to front and rear to rear) can inhibit inflation or catch on your reserve flap. You may wish to temporarily shorten your bridle line by tying a knot in it. The bridle line length should be 5 feet long or at the trailing edge of your parachute, whichever is longer. This helps avoid pilot chute entanglements during a stack formation. Remember to undo the knot before using the parachute on a regular freefall jump, else you may have a pilot chute in tow or hesitation. You should carry a hook knife, disconnect your AAD and reserve static line, wear long pants with socks and shoes. Your reserve ripcord should be triangular or D shaped to avoid snagging a line. Wear a helmet that does not impair your hearing, such as a bicycle helmet and not a soft leather hat. Spectra and micro lines are not preferred because of the relative ease they can slice through flesh.

The Exit

Your CRW instructor should exit the aircraft first. You should exit 3 to 5 seconds later. This exit, in the hands of an able instructor, guarantees separation during opening. Your CRW instructor watches your exit. If you wait the required 3 to 5 seconds, then your instructor can open at the same time you do, but horizontally and vertically separated from you. If you jump and dump immediately after your instructor jumped, then your instructor will wait 3 to 5 seconds before opening his parachute to ensure horizontal and vertical separation.

The Dock

A dock will be accomplished when you systematically eliminate separation. Eliminate vertical separation first, then horizontal separation. Once you and your instructor are at the same altitude, you both should fly on the arms of a "V" pointed into the wind. You'll be on converging paths. When you are about 20 feet (horizontally) away from your instructor (both jumpers must still be at the same altitude) you should turn away from your instructor. You must maintain straight, full flight. Take your hands out of your toggles and put them down and out to your sides, ready to catch the center cell of your instructor's canopy. Your instructor will not dock, if you have your hands in your toggles. If he did, there would be an immediate wrap as you catch your instructor's canopy and stall your own canopy.

After you catch your instructor's canopy, move to the center cell and put your feet around the A lines. Climb down the lines in a uniform manner. Once you reach the bottom of the lines, take your feet out of the lines and place them under the cross connectors, that are hiding underneath the slider. Then put your hands back into your toggles. Make sure your arms are outside of the centerlines, else breakoff will be painful. You, as the top jumper, will be steering the stack. Other jumpers can dock below your instructor.

Breakoff

Breakoff at 2500 feet. Step out and let your canopy fly full flight. Don't worry about catching your feet as you step out. The parachute will still fly as a stack even if you have one foot hung up. Relax and ease your feet out of the cross connectors.

Breakoff at 2500 feet. All CRW fatalities have happened when CRW was being done below safe altitudes. Wraps that have occurred above 2500 feet have always provided jumpers with enough time to execute emergency procedures. Breakoff at 2500 feet.

Emergency Procedures

There are no "hard and fast" emergency procedures for CRW. Each emergency is situation dependent, as to who cuts away first. The key to surviving a wrap is communication. Talk to your fellow jumper. You can easily save each other as kill each other. Generally, the top jumper in a stack is safest because he has an open parachute.

Post Dive

Canopy relative work skydives need to be debriefed, just as freefall jumps. Describe your jump to your instructor as best as you can. Obtain feedback, additional information and techniques from your instructor. Log your jump and go for another one. Have fun and be safe.

Originally published in Sport Parachutist's Safety Journal, V2, #2 Nov./Dec. 1989.
©Copyright 1989, 1996 by Jan Meyer. Republished with permission.

Dedicated to enhancing sport parachuting safety by disseminating information about equipment, environments and human factors.

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