Aerosoftware - skydiving

Find the Problem

by Jan Meyer

Remember when people used to say "If the guy across from you is a little bit high, you should get bigger." or "If the guy across from you is a little bit low you should tuck-up to get down to him."? The idea was to meet in the middle some place. What usually occurred was that jumpers passed through the optimal place and the formation disintegrated into a bunch of people scattered about the sky.

Nowadays, a method to avoid this type of problem is to designate someone to "set the fall rate". This jumper defines the level plane. Everyone else should match him. Low jumpers need to get back up and high jumpers need to get lower. The reason it works better is that the meeting place, in the middle, is well defined, that is, only if the fall rate setter doesn't change his fall rate.

Today, many jumpers forget the lessons learned earlier. Common errors are when jumpers say "The base should drop down a couple of feet when they transition." or "Pick up the fall rate when you go for the donut." This is not quite the optimal way to perform transitions. If the base jumpers drop a couple of feet as they transition they make it harder, not easier, for everyone else to dock. The same can be said about the base floating several feet after a transition.

Levelidity, everyone flying in the same plane, is first and foremost to building any formation. Levelidity needs to be MAINTAINED during transitions, not moved to a different place several feet lower (or higher) than everyone. If the base drops a few feet, then the group just lost the levelidity they need before completing the next formation. The rest of the group must reestablish levelidity with the base and then dock. This takes longer than docking on a base that maintains levelidity during a transition. There is also a greater risk of jumpers imparting vertical loads to the formation as they dock because they may dock from above, not level, with the formation.

A level plane is DEFINED by the person who sets the fall rate. The fall rate should be as fast as possible because maneuvers are easier and faster at faster fall rates. The fall rate should be compatible with the jumpers on the jump. It should be within the capabilities of everyone. The fall rate should be slow enough for the lightest jumper and fast enough for the heaviest jumper (Goldilocks Syndrome).

Every jumper has a wide range of fall rates. Everyone should practice flying the extreme edges of their own personal fall rate envelope on "no contact, follow me up and down by adjusting your arch" dives with other jumpers of various builds. It helps most dives and jumpers tremendously to jump with people of their same body type.

Levelidity problems will almost certainly exist between 100 pound and 250 pound jumpers. Many "couples" tend to jump together when they are both learning to skydive. Their problems are aggravated when their body types are mismatched. Usually the woman gets the blame for being a floater. She could learn faster by jumping with people with heights and weights similar to hers. Levelidity problems almost disappear when jumpers are the same height and weight. World champion teams have members very nearly the same body type. Increase the probability of success by jumping with people of the same size.

Fall rate problems can plague everyone. Remember the lessons learned many years ago. Keep the fall rate as fast as possible, but within everyone's range. MAINTAIN the fall rate during transitions as opposed to the make it faster and faster idea. Not only is it impossible to make the fall rate continually increase as the dive progresses, it is counterproductive. If the base floats during a transition, they should learn to MAINTAIN fall rate. Don't teach them to make the fall rate faster and faster. Emphasize fall rate maintenance throughout the dive. Jump with jumpers of similar size. Solve the fall rate problem the right way.

Originally published in Sport Parachutist's Safety Journal V2, #4 Jul. 1990.
©Copyright 1990, 1996 by Jan Meyer. Republished with permission.

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