Basejumper.com - archive

From your experience what contributes the most to an off-heading opening: Poor pack job, Bad Body Positon, Wind Currents (any other ideas) ? How often do they occur ? I also asume the bigger canopy you have, gives you the most time to recover from one.

Diego

Dude that is an extremely broad question.
You need to narrow down the type of Delay along with slider-Up or slider-Down.
( there is probably page opon page of endless dribble on What Causes off-headings in the forum-search )
.
Actually I never had my first true 180 till 300+ jumps.
Then I had like two in one month about 3 weeks later. - SoYou never know when or where.
I would say I had a good 5-6 good 180's in the first 500 BASE jumps.
.
Yes a bigger Canopy with a proper Brake setting is Slower on Movement than the same Canopy in smaller square footage.
.

ussually thinking "sh*t i really dont want it to open that way" gives me the worst offheadings... so i guess bodyposition..
but i also tried to let it open offheading by dipping a shoulder and it would open to the otherside it was supposed too.

maybe its just the mood your canopy is in

Yeah, that's in line with my experience. I find that having a cliff or bluff to one side (either from exit or due to a rotation in freefall) tends to give an off-heading toward the cliff. Some kind of magnetism, maybe?

mood = chaos theory?

http://www.imho.com/grae/chaos/chaos.html

sort of i guess =] anything can happen. maybe like the coin flip example

Another system in which sensitive dependence on initial conditions is evident is the flip of a coin. There are two variables in a flipping coin: how soon it hits the ground, and how fast it is flipping. Theoretically, it should be possible to control these variables entirely and control how the coin will end up. In practice, it is impossible to control exactly how fast the coin flips and how high it flips. It is possible to put the variables into a certain range, but it is impossible to control it enough to know the final results of the coin toss."

having more variables in a canopy opening =]

Fortunately it NOT just the - Flip of the Coin - When you are Making a BASE Jump.
Even with some of your most technical objects.
The Jumper Is In Control. / Control of all Variables and the Outcome.
.

Not true. Look up Persi Diaconis, who's managed a simple machine that flips heads 100% of the time. Without being particularly mundane about the flip. Word has it he can do the same manually.

Even very complex dynamical variables can often be controlled. Not saying it always works, but there's a lot more to it than (as one article posted here once said) jumping and "hoping" that the parachute opens.

The guy needs to be working on another simple machine that can pack on headings 100%of the time.

so if i understand you correctly an offheading is jumper error?

and of course i did not mean the flip of the coin like life/death. but just the highlighted part.... so dont focus on the coin, but on the theoratically controllable stuff and practical improbabillity (sp?) of controlling it.....

sure is.. if he walks away he wont get an offheadding

Packjob,tipping a shoulder,etc etc all jumpers issues only 2 things you cant help much is
wind(besides jumping in the best conditions only)
murphes law.."what can go wrong WILL go wrong"
its just a parachute

hehe true...

Is there?

There are, I think, only three causes for off-headings on a functional canopy. Perhaps somebody can correct me if I've missed something...

(1) Packing error;
(2) Body position at deployment;
(3) Wind at deployment altitude.

(that last can come in either directly, or perhaps indirectly through the PC). In every off-heading, each of the three comes into play to some extent or another; one could cite jumps in which any one of the three was clearly the dominant factor. Why each comes into play might seem obvious in advance or simply fall under "black death", depending on who's doing the looking.

Luck is not on the list.

Edit: Although part of this quote has now disappeared from the original post, I think the rest bears saying...

what do you call a blown toogle that cause an offheadding?
if that (usaly) aint bad luck i dunno

I call it "not a functional canopy". Of course, there are dozens of things that can happen to a parachute on deployment that will cause a turn after an otherwise on-heading opening -- blown toggle, lineover, tension knot, fabric or line failure, daisy chaining... To call any of these an "off heading" would be counterproductive, I think.

jejejelle
.... "so dont focus on the coin, but on the theoratically controllable stuff and practical improbabillity (sp?) of controlling it".....
-------------

When you say - ..."the flip of a coin." - What that means to me is. Or how I interoperate that is.
Just tossing your Pilot-Chute out and What ever opening you get. Just Deal With It.
I also don't assume on any set of facts or principles When I toss It out.
Theories on trying to gain or have control and theories why things did not turn out the way you planed them to. After you toss your Pilot-Chute out.
I threw that crap out the window a long time ago.

I don't believe or Assume to believe in any set of fact or principals involved with prediction of Heading Performance on Opening.

I Self-Empower with Fact / Repetitious Training and gaining awareness in depth of body position and awareness in my surrounding elements including the object I am standing on and always folding the Canopy fabric the same on Every Pack-job without deviation.

So there - Na Na NaNa Na -and- sticking my tongue out at you.
Now back to reading my Comic Book.
.
.

:)

thats what im saying.... you cant predict heading... you can try to minimize the chance by all you said.. and as long as you have distance from the object who cares about offheadings

A jumper DOES have control of the affects that wind has on his/her canopy!!!!

You have to assess what the wind is doing and then make a decision based on the information you have. If you don't have all the information, you either have not got the experience or skill to collect it or the relative motion of molecules in the air are far too complex for your mind to assimilate and determine. Haven't we all been there before!!!

Basicallly - too windy, no jump. Wind from such and such a direction, adjust deployment headings and gear configuration and use, etc.

What affects headings? You are off to a good start:

<<<(1) Packing error;
(2) Body position at deployment;
(3) Wind at deployment altitude.>>>>

Point 3 needs to be clarified. It is the relative motion of air molecules throughout the "deployment location" as opposed to just wind (which is I think what you mean anyway). This includes wind itself, thermal activity (i.e. temp induced, adiabatic, etc), turbulence created by interaction of the motion of air molecules and obstacles in solid/liquid/gaseous form, etc.

Another factor is relative wind during deployment. The canopy can be / is affected by the turbulence around the jumper and the deploying canopy. The turbulence varies depending on freefall speed, body orientation, surface area exposed to relative air flow (think small (boxman position) versus big area (wingsuit)), horizontal motion (tracking versus straight down), the shape of the falling mass during deployment (arms and legs all over the place will create "messier" turbulence than a perfectly symmetrical and uniform shape), etc.

Then you have to factor in things such as forces imparted on various parts of the system and their relative timing (i.e. dropping a shoulder will load one riser/line group prior to the other which will affect the timing of pressurisation and inflation across the planform area of the airfoil, etc - which will in turn allow one component of the wing to function prior to the other, which . . .) blah blah blah -> off heading!!!

Then there are factors such as the airfoil design itself.
What about the relative aging and degredation of various parts of the system? i.e. if one line is stretched more than another it will contribute to turning forces during deployment (remember what some of the clues are when a canopy needs a reline - off headings, harder openings, irregularity, etc).

We can now go a bit more complex and theorise on how each of these factors may combine to cause an off heading. i.e. if there is only one factor present it might be OK but if we introduce several variables at once then we are more likely to get the off heading - i.e. worn gear by itslef may be OK but if we throw in questionable body position it may exaggerate the problem.

Then there is . . . . .

some people believe in higher forces and powers and luck and stuff!!!!!!

Overall, if you want to keep things simple. I think IMHO that body position is 80%, packing error is 10% and choosing (subconsciously or not) to jump in questionable wind conditions is the other 10%.

Packing error is relatively easy to eliminate. Learn properly and follow that procedure/method.

Wind is a little more difficult as we are all human and we don't have the patience or skill/experience to be able to detect and allow for all wind situations. But is you think its dodgy, go with your gut instinct. Why? Being BASE jumpers, many of us err to the courageous side. So questions in the mind are probably there for a good reason.

Body position is probably the trickiest of them all. Why? Although we can do a lot of training and develop our skills progressively, you are usually already in the moment (i.e. in freefall) when the body position starts to feel questionable. Packing and wind you can make a decision on before you exit. The best solution is to develop your skills in a logical order (pca, boxman, track . . . whatever), plan your entire jump (including your exit) prior to your jump and follow through on your plan. Your plan should include responses for all scenarios (head down, off heading, etc) BEFORE you jump.

Other than that, pray to your local God. She/he/it may help.

p.s. Now, when you have an off heading, you should go for your:

A - Risers
B - Toggles
C - Handkerchief
D - Cutaway Handle
E - Appendage

?????? That is a whole other story!!!

Always go for the appendage first!

Go for your eyes. Cover 'em up; I find imminent object strike is a lot less frightening if you can't see it coming.