What assisted deployment method gives you the fastest opening...ie inflated, flying canopy. My thoughts are a SL if you use say 80lb. break cord. Unless someone holding the PC is stronger??? And what about a Dbag?? I guess with a dbag you don't have to consider canopy extraction. I don't know if this question makes sense, hhhhmmmmmmm. its late. :-)
Ok, some will disagree but I believe this sums it up:
Static Line:
:P Pro's-Very reliable IF you're smart and use a logical technique. You also don't have to trust anyone but yourself. S/L gets you open relatively high with good on-heading performance because your anchor point is fixed.
:-( Con's-All the different ways to do it can be confusing and dangerous for some people. There's no one right way, but there are a lot of wrong ways. And no single technique will work on every jump, you have to be able to evaluate the situation. Not a good choice for most buildings, antennas, cliffs or anything sheer/underhung because the breakcord holds your canopy back close to the object even if you launch hard.
Direct Bag:
:P Pro's-Gives you a higher opening, generally, than S/L or PCA. Has the greatest probability of a perfect on-heading. A better choice for sheer/underhung objects because the canopy tends to "launch" away from the object and there is no pc or bridle to get snagged on something.
:-( Con's-Very messy and inconvenient. You will have to repack your rig to do this. You also have to trust someone to hold your bag straight and not give you a 180 or line twists.
PC Assist:
:P Pro's-No rigging involved. Simple and reliable; a monkey can be trained to hold your pc. A much faster and cleaner method for almost any situation.
:-( Con's-Some people just aren't as smart as monkeys. It is possible to induce an off-heading opening if the pc is held at an angle from the jumper. Also, if your pc is dropped prematurely, not only will you get open slightly lower, but your canopy can do some amazing acrobatics during line stretch if the bridle suddenly loses tension. I guess that is a danger for static line as well, if the breakcord were to break prematurely. Consider that the center of gravity of a deploying canopy is near the bottom, at the tail pocket. If something pulls the canopy out halfway then suddenly lets go, the inertia of the tailpocket keeps moving up (relative to the jumper), but the top part of the canopy recoils toward the jumper, which will result in an upside-down or severely contorted canopy. Call it a worse-case scenario, but I've seen it happen on a botched PCA.
I don't have a lot of first-hand experience, but for what it's worth, here's my thinking:
A static line puts 80 lb of force on the bridle attachment of the deploying canopy. When the static line breaks, this puts a bit of a "rebound" into the canopy and can add to the time it takes for it to open.
A d-bag eliminates this tension, so the canopy can expand freely once it's out of the bag. Also, it eliminates about 6 feet of bridle (more if you use a multi, which could reduce the effects of the static line rebound), so automatically you're open 6 feet higher. I've heard heading with a d-bag is sensitive to the way it's being held.
The only PCA I've given anyone so far resulted in a bit of a strange opening, because I had a death grip on the pilot chute. If you hold it tight enough, you will apply more than 80 lb of force to the bridle attachment, and the rebound will be that much bigger. A skillful PC handler could determine when the jumper has reached line stretch, and let the PC go with minimal tension on the bridle attachment.
It seems like the PCA would offer quicker set-up than either static line or d-bag if traffic is an issue.
Michael
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