Why Static Line over IAD?

[MrBrant 0]

Since it would probably make more sense to keep THIS thread on-topic, I am wondering, why would S/L be used instead of the IAD method?

I learn't via IAD, and am under the impression that it is the 'newer' and 'better' form of staic line.

Is it infact 'better'?
If it is 'better' why are jumps still done S/L instead of IAD?
Is there some pro's of s/l that get lost in IAD?


Thanks,

Brant

[tombuch 0]

I learned through static line 'back in the day, when it was all we had, but now I have both SL and IAD ratings.

SL is a great way to deploy a round parachute, but IAD offers a more staged and comfortable square deployment.

A direct bag deployment with a static line does a better job of assuring the canopy will actually open. With an IAD there is a greater chance of the student sagging the pilot chute, or the pilot chute going over the tail of the airplane.

Either method is fine. IAD requires a bit more attention from the instructor, but if that attention is provided it's a fine way to learn.

Tom Buchanan
Instructor Emeritus
Comm Pilot MSEL,G
Author: JUMP! Skydiving Made Fun and Easy

[riggerrob 643]

The flip side of Tombuch's opinion is that I have dropped so many IAD students - over the last 22 years - that it is second-nature to me.
Those few weeks out of the year that I drop static-line students, I have to constantly remind myself to keep the static-line clear of their arms, legs, feet, etc.
Generally, I prefer IAD because it wears out equipment at a slower rate.

[tombuch 0]

Quote

Generally, I prefer IAD because it wears out equipment at a slower rate.

Try flying the student position on a SL and IAD jump. You will probably be sold on the comfort of the IAD openings too.

I hated the IAD program until I wrote my book. At that point I decided I had better learn about they program if I was going to trash it in print. So, I set-up a dual SL/IAD rating at my DZ and added the IAD to my old time SL rating. One jump in the student position deploying a square with a SL from the Otter was enough to convince me that IAD is a better method for modern parachutes. Along the way I probably watched about 50 IAD and SL jumps tossed one after the other, and that double convinced me.

Writing JUMP! Skydiving Made Fun and Easy was a great experience because it forced me to do real research and confront a lifetime of bias. I came out of it far better informed, and with a much deeper understanding of the sport. I can't tell you how many of my opinions changed along the way!
.

Tom Buchanan
Instructor Emeritus
Comm Pilot MSEL,G
Author: JUMP! Skydiving Made Fun and Easy

[sstovall 0]

How does IAD make the opening more pleasant? I learned via static line at a 182 DZ and the openings were never uncomfortable. Seems like it would be more natural (normal freefall opening sensation) by static line. The way ours was set up was with a spring loaded pilot chute and the static line was for all purposes just a self removing closing pin. I don't see how someone chucking your pilot chute would be more comfortable.

S

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-some will fall in love with life and drink it from a fountain,
that is pouring like an avalanche coming down the mountain

[billvon 2,991]

> How does IAD make the opening more pleasant?

There are two kinds of SL out there - direct bag and PC assist. Direct bag has the SL directly attached to the bag; the SL both pulls the pin and hauls the D-bag out. Since the relative wind is coming from the front of the plane, and that's approximately where the SL pulls the bag, the parachute gets pulled slightly in front/above the student before it clears the bag. This exposes the main parachute to wind from an odd direction; funky openings can result.

In PC assist, the static line just pulls the pin, and some velcro helps the PC come out of the container. (You can pack a throwout as a PC assist; you just put the PC inside the container, like a pullout.) These openings are much more 'normal' since the PC is doing its usual job of launching the bag away (downwind) of the jumper.

IAD is similar to PC assist when it comes to openings, since both use the PC in the same way.

[teason 0]

In an ideal IAD student exit, the pilot chute is released just off to side of the jumper. It should be roughly the same distance from the body as a normal pilotchute deployment. This is opposed to the direct bag static line method which experiences "sail effect" after it leaves the bag.

There are pros and cons to all the systems. D-bag static line is unnatural (sail effect), PC assist opens the container with the PC in the vicinity of a flailing jumper(horseshoe) and IAD students can tangle in PCs causing total mals, potential horseshoes and the previously mentioned sail effect.

The biggest drawback to IADs is that the instructors have to know thier shit. Bad and slow throws and poor reactions to unpredictable student actions will increase the likelihood of bad situations.

The biggest plus to an IAD is that a competent instructor can control the student and take corrective action. With the right instructor out on the strut, the likelihood of the "righthand slip" can be almost eliminated.

If you have current, competent instructors then IAD can be great. If not then S/L is probably the best bet. (Not to demean S/L but IAD is more instructor intensive)

Admitedly, my S/L experience is VERY limited but I have done several thousand IADs

I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet.

[FrogNog 1]

Quote

There are two kinds of SL out there - direct bag and PC assist.

Bill, how would you classify a system where the SL pulls the pin (or shorty ripcord - same diff) then is attached to the base of the spring-loaded PC with Velcro, so it opens the container and helps ensure the PC comes out of the container and holds the bag until linestretch?

This seems to be a variant on the direct-bag method that adds redundancy in case the static line should somehow separate from the bag/PC prematurely (but after pulling the pin), plus allows the same student rigs to be used for static-line jumps and the later freefall jumps.

-=-=-=-=-
Pull.

[karenmeal 0]

Quote

In PC assist, the static line just pulls the pin, and some velcro helps the PC come out of the container.

This is what our DZ uses.

Was that what you were asking, Eugene?

"Life is a temporary victory over the causes which induce death." - Sylvester Graham