The inevitable

[Mike]

Ok so the other night I had my first 180 off my local A. The winds were humming a bit faster at 500' than I would have liked but parting the guywires nicely. I was feeling relaxed and confident so I decided to go. I felt stable on exit and threw, to open to three quarters of a line twist. At this point I'm pretty sure I remember looking down the left set of wires and looking up to see risers crossing each other. By the time I spread them out and squared up with my canopy, I was facing almost directly at the steel. I went for both rear risers enough to stall and back up a bit with the help of the winds. I popped the toggles and turned the canopy around to do a downwinder which I rolled out. The landing area is very large and flat and forgiving = many outs.

Now I have been going through the archives looking for 180's and such. I've come across a few posts and replies integrating high winds as a possible cause for 180's. They stated that a canopy could catch air on one side and spin to cause an offheading. Some also determined a canopy is by nature wind-hungry (for lack of a better term) and will maneuver it's nose to seek wind. I'm kinda up in the air as to what to think. I think a canopy is already getting a lot of wind at line strech and wouldn't be effected by higher lateral winds, provided they aren't hurricane force.

I feel I had a good pack job, tailgate properly installed, solid exit, good position after throw, etc... I understand s**t happens even when you make every attempt to prevent it, but I'd like to hear some thoughts on higher winds and offheadings. Are they linked together?

Never the less, that's the last time this fat little irishman will be jumping in those winds again. Next time I'll head out to the bar instead.

Careful out there!
Thanks!
mike

[guest]

Wind is your friend on an A. I only get scared on a tower jump if there is no wind. If it was smokin like you mentioned, a tower strike seems extremely low probability unless your jumping a hi=perf skydiving canopy.
more knots=less knuts!

[MT]

Can't say I know the Irish BASE jumper called Mike? When were you last in Ireland?

[guest]

I had my first 180 about 3 weeks ago. 600ft overhung power tower. Nil winds, corrected on toggles, all ok after. Morpheus Big Grabs are the mutts nuts!! :+
Afterwards back to pub where the beers were on me!

Isn`t there a saying, there are those who`ve had 180`s and they`re are those who`ve yet to have...?

Be safe and low

[guest]

I have never had an off-heading that I could attribute to stong winds directly at my back. After all, symmetry is maintained in that situation. I have had off-headings that I attributed to a strong cross-wind. The hypothesis is that a cross wind will take your PC and your pack job off your back at an angle, the angle being more pronounced at low deployment speeds and high wind speeds. When line stretch is reached in this scenario, if your shoulders are level, line stretch will be reached on one pair of risers first due to the angle. This asymmetrical loading causes a turn towards the side that is loaded, just as if you pulled down a riser on that side during normal flight. Therefore, the turn induced should be into the wind.

That's my theory anyway. If the wind was directly at your back, I would look for another explanation. How long a delay did you take?

[imported_Tom Aiello]

>I think a canopy is already getting a
>lot of wind at line strech and wouldn't be
>effected by higher lateral winds, provided they
>aren't hurricane force.

In my opinion, the governing factor is wind speed. The more your relative wind speed exceeds the tailwind speed, the more you govern the opening. In situations where the natural wind greatly exceeds the relative wind created by the jumpers speed, I expect the wind to govern the opening.

We have a local wind-through object that is regularly jumped in relatively high winds, and I can't count the number of times that every jumper on the load has had the exact same 135 Left opening, directly into the wind.

--Tom Aiello
tbaiello@mac.com

[guest]

Congratulations on your new membership to the 180 club.

High winds are your friend. After making about 300 A jumps from many sorts of A's at all types of altitude, I'll say this with confidence.

You canopy will act like a windsock, so if your jumping down the windline, you're canopy will more likely open on-heading. If you're jumping in a significant crosswind, your canopy will more like face down the windline, but there still is a chance it will face up the windline. My only concern with the wind is in some cases the extreme tail first inflation that can cause some malfunctions. The tailgate has been very useful in reducing the slider down line over situation.

Go to the object instead of the bar.

[space]

mike wrote;
> and looking up to see risers crossing each other > crossing each other.
So here is the deal on this, you had a deployment 180, which means that your canopy turned before it got to line stretch, as opposed to a flying off heading, Normally this is a result of only 3 possible things according to what i have done and seen.
a. Turbulence at opening alt where one side opens before the other,
b. Line twist during packing,
c.jumping an improperly built or asymmetric or asymmetrically installed PC.
what would help me to help you is to tell me...
How many jumps did you have with this same setup? when did you change it to this set up? is the rig still set up in the same as when you had the nasty Off heading? Let me know and I can get you sorted.
take care,
space

[guest]

I have jumped this setup about 8 times and had one 90 in each direction. I've praticed patience in packing and inspection because most of my jumps are virtual solo's. This jump I took a 2 second delay so I suppose I may not have had sufficient speed to overtake the winds. Possibility?

thanks

mike

[space]

So I have some questions for you,... should we do it here in the forum, or via email? your choice... anything is cool with me..
take care,
space

[crwper]

Hey, it would be great if you guys could continue the discussion here, as I think we can all learn from this information. Thanks!

Michael

[guest]

I appreciate the help and would answer anything here!

Mike

[space]

Ok here we go,
I will focus on the PC first.
Did you attach the PC immediately prior to this jump or has it been an unchanged setup?
Is it attached symmetrically(step on the bridle, pull on and compare the lengths of the load tapes at the skirt of PC)?
Does the bridle have twists in it relating to the same direction of your 180?
Is your PC Bias constructed as opposed to Block?
Is your PC the optimum size for the delay?
Kick back,
take care,
space

[guest]

My PC is 46 inches and it is centered correctly on the bridle. I had a 2 second delay and it is an F-11 material. I figured that 2 seconds was fine. I recently changed from a slider up configuration to a slider down. Checked the routing and set the tailgate. And I have not noticed any more than one or two twists on the bridle at any time of repack. I check my routing before I climb my object. I actually reach back and route the bridle before and after my PC prep. I always pause for a quick moment of exhileration then go.


Open to suggestions
Thanks!
Mike

[space]

Ok here we go number 2.
I will focus on the PC first.
Did you attach the PC immediately prior to this jump
Yes or no?
Is it attached symmetrically(step on the bridle, pull on and compare the lengths of the load tapes at the skirt of PC) Now?
Yes or no
Does the bridle have twists in it relating to the same direction of your 180?
Yes or no?
Is your PC Bias constructed as opposed to Block?
Yes or no?
PC problems are the most common, let us find out if this is/was a prob, then we can
narrow it down.
Take care,
space