From BLiNC Magazine

Pilot Chute Openings

Posted in: Deployment
By Mick Knutson
Jan 30, 2002 - 8:55:31 PM

Pilot Chute Opening Generally you can say a larger size pilot chute will provide more pulling power than a smaller one. However, that depends on how it's built. A pilot chute has a trim setting that determines it's pulling power and this has to do with how much you pull the apex down. (Controlled by the centerline tapes). This is set during the manufacturing process, so two pilot chutes the same size could vary from manufacturer to manufacturer. As for deployment time, that's a tough one. There may not be that much of difference unless we're talking really small pilot chutes Vs really big ones. Across the span of the most popular BASE sizes (42"-48") there may not be much of a measurable difference in time of deployment. At one time 52 inch pilot chutes were used for almost all BASE jumps. These were big and heavy and if thrown hard enough on a short delay they would angle your deployment out in the same direction. (The most popular ones are called Hank 52's for the rigger who built them. These were originally designed and sold to the military to retard the fall of bombs). Over time BASE jumpers realized 52 inches is a bit of overkill. And some other problems were starting to surface. The drag retarded the flight of the open canopy. Folks who are still BASE-jumping with nine cell canopies are getting bow-tie type openings, and since retired skydiving canopies are what most are jumping we started to see bridle attachment points begin to fail. If you are planning a BASE jump where you are counting on a certain size pilot chute to provide a faster opening you are cutting things too fine.

It's like when Jump Shack advertises the speed of their reserve deployment being faster than other rigs that have the reserve pilot chute inside the container, well, they are counting on many things going right for that to be true.

When thinking about available altitude and how best to use it always factor in room for a line over and a pilot chute hesitation and you will never die.
Unless it's your time . . .

Nick-BR
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I read an article in Skydiving Magazine some while ago about using a too big pilot chute for a specific delay and that "the bigger the better" would not always yield.

I remember it was something like that if the pc is too big it pulls too hard on the center cell and therefore stretches it too much in the vertical direction. Because the center cell gets pulled out of shape the opening with such a huge pilot chute could actually be slower than with a well chose pc size.


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