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Why does a 180 happen.Is it down to your exit or proximity to the wall,or is it how your weight distribution hits the opening,like at what angle to the cute you are,when the lines strech????

Yes, yes and yes.
It could also be the pack job .
It could also be that with a perfect body position and a perfect pack job a 180 will just happen anyway. Its not if but when you get the 180 , to survive you will need preconditioned reactions from years of skydiving as well as reactions like lightning , and even then that may not be enough.
So why don't you stop with your stupid quest to base off an unjumpable cliff on the north face of ben nevis for your first ever jump and fuck off to a dropzone and learn how to skydive.
If you continue Jonny,if you are going to be dumb , then you are going to have to be very tough.

I don't see what close proximity to the wall has to do with 180s unless your talking about slow speed slider up wich is pretty inconsistent

They just happen. Blind dumb luck. The perfect pack job that screams "I'm perfect! Jump me off something important! I'm perfect!" Those are the ones that will get you!

I said that on impules,i now have no plans to jump from nevis lol.I now realise i was planning a death jump.I am going for a fixed line course soon.Going to learn to pack a chute,not rushing anything,my plans is to learn how to skydive first.I dont wanna be number 178.

Damn good idea!

You should learn to skydive and do some simple research before asking simple questions that have already been answered.

http://www.basejumper.com/...Offheadings_719.html

The major contributing factors to off heading openings (including 180's) appear to be:

Wind
Body Position
Pack Job
Plain old Black Death that Tries to Kill You


Which of these is the dominant factor depends on the exact situation (and also on how badly Black Death wants to kill you today).

In general, if the jumpers fall rate is less than the wind speed (short delays in fairly high winds) I would expect to see wind become the dominant factor in determining opening heading. I think this is slightly less true in tail winds, and slightly more true in head/cross winds.

On high airspeed (especially terminal) jumps, I think that the jumpers body position at opening is usually the dominant factor.

Pack job appears to mostly be a factor with very bad pack jobs, especially those with substantially asymmetric fabric folding forward of the B lines.

In my opinion, fabric behind the tailgate has virtually no effect on opening heading, as the canopy will already have established heading (with an open nose) before that fabric sees any airflow in the inflation process.

The most important part of the canopy for opening heading appears to be the central joint where the center rib meets the bottom skin. Fabric becomes less important as you move back and up from that point, so basically the most important fabric for opening heading is the center of the nose, and the least important is the topskin of the tail.

Assuming that the lines are managed in a fundamentally correct manner (brakes stowed the same, tailgate set etc), I don't think that the lines have much effect on opening heading. However, the lines appear to be the main factor in actual parachute malfunction, so I personally think they are more important than the fabric in any pack job.


And then there is Good Old Black Death. Sometimes everything seems good with regard to body position, pack job and wind, and yet we still see wild off headings. That's just part of BASE, at this point in the development of our technology. If you can't accept that, I'd suggest changing your object selection, or perhaps looking into parachuting from aircraft, which is an enjoyable and interesting activity.

Im asking becasue im in the beginners section.If i post in the big boys hang out,and come out with some nonsense about jumping of nevis,then fair enough slate me ,Whats wrong with asking(simple) questions in the beginners section.And to be honest it seems like a big question after reading all the fatalitys,becasue the majority of them seem to be a wall strike after a 180 on exit .Im not here to fight,i want to learn,but i will come out with some dumb shit.Its the nature of being a beginner

Nothing. That's what the Beginners Forum is for. If people don't want to take the time to read and answer, then fair enough, there is no need for them to do so. That's why these posts are in this forum--so that experienced jumpers will know what sort of content is in here before they click on it.

Sorry, maybe my response came off in-correctly. What i meant was...

Hey John,

I've been where you are, I was once a broke in debt skydiver, that wanted to learn to base jump, got a cold shoulder everywhere I turned, and couldn't afford a course. I quickly found asking questions on the forums got answers from so many different angles, some jokes, some serious, some out right bashings it was hard to decyfer good info from bad, and could become quite irritating. So, I poked around and discovered the articles section here and on blinc, and base.org ect and began researching every angle of base that i could find and taking that knowledge to the dropzone for practice in tracking, heading control in openings, accuracy, blah blah blah. When not skydiving I practiced exits into a pool over and over again from a diving board. If you exit properly for a base exit you'll hit the water at a 45 degree angle knees first, if not, your gonna belly flop and it's gonna suck. After eight months of this I started base jumping. So Maybe you could do some research like i did and learn some things, practice at the DZ, and correlate with other jumpers on finer detail with what you have already learned here.

Ex. Hey I read the article on heading control and began practicing body maintenance and control, I even turned my camera around backwards to video my openings. All seems to be well from the article points, but I'm still opening off heading every jump. I noticed my PC is flailing in violent circles behind me from the video, could this cause off headings?

A question like that would probably produce a very educated answer from someone like Tom about the effects and causes of PC oscillation. Someone like Yuri might even chime in with a scientific view about the karman vortex, arcadian effect, resonance, burbles, and other such stuff and how to overcome it with vented pcs or f111 pc's.

Hope that cleared up my intentions, didn't mean to come off in an attack.

"Why does a 180 happen.Is it down to your exit or proximity to the wall,or is it how your weight distribution hits the opening,like at what angle to the cute you are,when the lines strech????... "

Simply searching "180" will award you 1650 results. Someone's being lazy

Pilot chute oscilations have been known to cause off headings as well. Pilot chute oscilations can be caused by an asymetrically attached pc, an asymetrically manufactured pc, or a pc that doesn't vent effectively; ie a zp pilot chute without an apex vent.