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scenario: 300ft freestander, 46 pc, vtecmultifox, 1 second delay, 8-10 mph crosswind from right to left, lz on front and to left...

result: 180 offheading, two twists and chin pinned to my chest,

action taken: reached above and behind me to get lines as im flying at object, thinking "wtf", pulled first riser i got a hold of (above the twists) just so happens it was right front, turned to R (obviously) went to right rear came out of twists passing corner of object,(6 feet)
popped brakes, stand up landing..


so. do you see anytihng here that i didnt conditions or otherwise? packjob was s/d, same as every other s/d pj ive done..

my canopy tried to kill me... and all the "climb above twists and pull rear etc.. goes right out the window, when you cant even look up to save your ass...

I'm just glad it wasn't the left front riser you got a hold of.
I'd crack a cold one and eat a pizza.

Congradulations.

Focus on the PC. had you jumped it in this config just before without changing anthing? Or did you change your PC for this jump? Symmetry of your PC to bridle would be my first guess. Body position/relative wind would be the 2nd.
Let us know,
take care,
space

 

I do not know why you had a 180 ... it happens, just try to survive it.

But some things I do know or at least experienced. I’m preaching against the multi if you to not jumping low stuff … that’s Belgian low.

DW was a preacher for the multi, we discussed for about a year but never came to the same conclusion. Some things we agreed about. Body position is paramount.

My self have a body position in the proximity of a first timer, DW did aerials on axis (is that the word for it?) so that’s a big difference … there we are … cross wind.

Cross wind is like bad body position … bad body position is you are fucking up under your extracting canopy and cross wind is your canopy fucking up above you perfect :) body position … not really fucking up but it moves to one side and put tension on one riser before the other :)

With multi the off heading is going to be more direct and more violent … just more bottom skin there for you and some pivot stuff if you like to get technical about it … I did about 100 jumps with the multi in cross wind before I took it off.

My canopy usually open up wind I cross wind … with multi or nor not but with multi it is more violent and I spend a second to press the riser to not induce a linetwist with my body instead of get my canopy re-directed.

PerFlare

Nearly every time that I do a SD ~1sec. delay in a crosswind my canopy tends to open offheading facing directly into the wind. I've got a sequence of still photos where you can see the packjob spin around 180 right above my head well before the canopy reaches line stretch. I think that it's really a matter of relative wind hitting the packjob as it's slowly pulled to line stretch combined with the direction that the PC is pulling it.

same exact scenario. THe pics attached was in crosswinds ~~ 10 or so from left to right. I believe everybody on the load had 90 lefts (into the wind).
I think it's alot more of a PC pullng the packjob to the side then the packjob being shifted by the wind. I do think the wind shifting the packjob may contribute to a 180 though. (kinda like 90 induced by a PC, and another 90 induced by the packjob shift).
but what do i know ...

pc was changed for this jump... i had jumped this same object a week ago , taking same delay with a 42, and everything worked out just fine, same crosswind, just LtoR that time... i made a concious effort to ensure correct pc/bridle attachment, but who knows... how "wrong" does it have to be to induce oscillations?

interesting bits about the multi, and valid considerations as well...just one more extra step to configure..

i had anticipated a bit of an oh due to crosswind, but this was a bit much...

thanks for inputs...

Hi,

Well ... yes. That's pretty much what I said?

PerFlare

Now that's a disturbing photo. Here's something I've never thought of before:

Suppose the crosswind is from the left. You jump, you pitch. The PC moves to the right slowly as it pulls your canopy out. By the time your canopy is nearing line stretch, the line from you, through your canopy, and to the PC is angled to the right.

Now, take that line, and imagine how your canopy sits on it. Looking from the front, you see the exposed nose of the canopy, and the whole packjob is kind of cockeyed, tilted to the side the PC is pulling from. The natural tendency of the packjob will be to slump toward the bottom side of the line. From the jumper's point of view, that means it's going to swing so that the nose faces left. The risers aren't even loaded, and already your packjob is 90-left.

I suspect this effect is independent of whether or not you have a Multi. At this point, the Multi is still closed.

Another interesting thing is that this won't happen every time. It's possible you will get lucky and your packjob will be relatively well-balanced on the line. In that case, it may not rotate at all before it begins to inflate (at which point it becomes much more stable in regards to this kind of thing). But it means that crosswinds are a bit of a crap shoot, which I think we all know from experience.

Michael

I have to say that photographically – that's one of the best BASE photographs I've ever seen. The composition is right, the light is right, it tells a story, and it gives you chills.

If I still did a BASE magazine – it would be the next cover shot . . .

NickD
BASE 194

That's a great picture. I keep thinking about this and go through scenarios of how and why, but that picture says a lot. The PC pulls the pack job out downwind of the jumper. This induces a slight turn as the lines are pulled from the tail pocket. This turn has the nose pointing into the wind. The canopy opens nose first and you have your 90 off-heading.

If the lines coming out of the pocket take a little more energy to clear the turn induced is greater and the nose is pointing further around.

Now I'm not saying this is what happens, but from that particular picture it would be easy to create a theory similar to the above. Prior to seeing that picture I thought the opening into the wind was probably caused by the nose catching air.

hey, PM me with where that tower is. i think i have jumped it. and after seeing the picture, makes me regret it even more. Microwave is BAD shit

Just so proper credit is given, the photo was taken by Eliott "blitzkrieg". I have cropped it and photoshoped the colors to my liking

my experience is that multi and x winds are bad juju,i took mine off for the same reasson..

Has to say that if i can get the perfect wind,and body position each time i jump i would start using the multi again,the idea is brilliant,but in x winds i just have experienced too many offheaddings..

good work getting out unhurt..

Brian I know what happened u were probuly smoking crack and doing whippits why u were packing and packed it in there your self lucking for u your one part ninja and won part super fucking human.

The Multi was designed to prevent center-cell stripping

--------------------------------------------------------

What is center cell stripping?

JP

exactly as it sounds. it basically pulls out the center cell first and leaves the rest behind. the multi will pull the center cell and a few other cells with it so that what gets initially presented to the wind it is move even.

I've got roughly 400 A jumps, and It's my opinion,that crosswinds and short delays will always lead to an offheading of some type. The only way to take the crosswind out of the picture is to take a longer delay to increase the relative vertical wind speed. 90percent of the time the canopy will turn into the wind. Combine with a orbiting PC and bad body position, and you have a recipe for disaster. Packing has almost no effect on opening heading(for all you clampers) The most pefectly ironed canopies will turn just as much as a sloppy pack job.But then again, it's all just Theory