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TomAiello

Antenna Guy Wires and Wind

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Yuri posted this in the "High A" thread. This is very important information, and, in my experience, the vast majority of jumpers do not understand it. I've reproduced it here, and I'll sticky it to the top of the board for a few days.

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>"stronger the wind the higher necessity for the wind to perfectly bisect the wires"

This is a very common misunderstanding about antennas. Let's have a look:

The most dangerous condition is no wind at all (just when it feels so peaceful and safe...). After an off-heading opening you will be flying towards either of the wire sets at your canopy's speed in brakes.

Any wind down the wire is a much better case. If you open facing the downwind wire, you speed vector towards it is still your canopy's forward speed. If you open facing the upwind wire you are flying roughly at your canopy's speed minus the wind speed. Stronger the wind, safer you are. In a strong wind (at or above you canopy's speed) exiting almost parallel with the upwind wire (0..30 degrees off) gives you the most safety margin: 90..120 degrees free sector on the downwind side. The upwind off-heading is safe because you have no penetration and/or your canopy will be backing up. You will also open a bit further away from the downwind wire.

Obviously, the safest situation is a strong wind exactly between the wires.

Draw yourself a little picture with 3 lines at 120' angles representing the wires and 2 vectors representing speeds and directions of your canopy and the wind. Add these 2 vectors and everything will suddenly make sense. If their sum is pointing away from both wires no matter what direction is your canopy, you can throw a monkey off safely. Otherwise some prompt steering response will be required in case of an off-heading opening.

You must consider the wind at your opening altitude - NOT at your exit point. The wind will frequently turn as you climb up (usually to the right in the Northern hemisphere and to the left in Oz). Sometimes it turns enough to cross into another sector, and will be a big mistake to follow the wind and exit on the wrong side of the wire.

bsbd!

Yuri.


-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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***In a strong wind (at or above you canopy's speed) exiting almost parallel with the upwind wire (0..30 degrees off) gives you the most safety margin: 90..120 degrees free sector on the downwind side.



Hmmm....

Seems to me that the optimal exit is 90 degrees from the down-wind wire under these conditions, and not anything more. A 110 degree exit is similar (with respect to the downwind wire) to a 70 degree exit, in that your separation from the plane of the downwind wire is the same, putting you that much closer to collision in the event of a 180 (or, to be precise, a 160 degree opening, facing the plane of the downwind wire). Also, note that with a 110 degree exit, openings greater than 70 degrees in the direction of the upwind wire (more than directly into the wind) may give you resulting vectors that actually intersect the upwind wire (see attachment). The closer you are to the upwind wires, the dicier this situation becomes.

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y'know--the other option if the wind is blowing from a direction that you don't like for jumping is DON'T FUCKING JUMP!

mh

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Damn, mother i'm with you! it started out as a nice write up then someone broke out the BIG box of crayola's...now i'm just as dumb as i was before the original post..

no but for real now.. Thanks Yuri as always your knowledge has been helpful. I myself have been on the top of towers and had the wind change directions on me from exit to open and to tell the truth a few times i have climbed down. had i had this info then i would not have wasted so many steps....in the wrong direction.
big country
base998

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I won't put it so elegant but I once heard Yuri say something to the effect of "Conditions are always perfect to jump. Its just the outcome that is questionable." So I say get out there and go for it.:)

Matt Davies


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I just had a 160 Deg. off heading last night.
on a Tower jump, and I am confused.
After reading that Post.

optimal exit, 110 deg. exit, to a 70 deg., separation,
plane of the down wind wire, closer to collision
in the event of a 180. or to be precise a 160
facing plane of the down wind wire with a 110 deg. exit
opening greater than 70 deg. in the direction of the upwind wire
(See Attachment)

All you had to say was the last sentence.....

The closer you are to the upwind wires, the dicier this situation becomes.

The wind is your friend on a Tower jump.
Dont fly into the Wires.

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Yuri say something to the effect of "Conditions are always perfect to jump. Its just the outcome that is questionable." So I say get out there and go for it. :)


We gonna flik one day mate:ph34r:
By the wind thing,i wont recomend jumping slider off stuff/pulling low(also by slider up) in nuclear winds... i have found out that not always your legs can out run a 265(downwinds):D the result is dirty gear and clothes,but then again.. its all fun:o:ph34r:

IF you have time to turn your canopy up against the winds it can also be hard to run faster backwards that your GC can run forwards to catsh you(thanks Peter the vid looks soooo fun:o:ph34r::D)

As Mother said,if you aint in for it or dont like the results of jumping thouse winds,then simply dont jump:P

Stay safe
Stefan Faber

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I just had a 160 Deg. off heading last night.
on a Tower jump, and I am confused.
After reading that Post.


he he look at your packing skills,dont pshyco pack it:P

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The closer you are to the upwind wires, the dicier this situation becomes.


sure does,some plans to opens so they are between the weires,in case so they can fly between them,for serval reassons i dont agree whith that,i see the weires as "walls"which would hurt to fly into.
But thats just me.

good job not flying into the weires...

Stay safe
Stefan Faber

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What are the typical set of outcomes for an antenna wire strike? I can envision 3:

1. If your canopy hits the wire, the chances are you could back it off.

2. If your lines hit the wire, i.e. your canopy is trying to fly above the wire and your body is below it, then this would probably be the worst case scenario, because of the likelyhood of canopy collapse.

3. If your body hits the wire, this is somewhat of a combination of both 1 and 2 above.

Anyone with experience in wire strikes care to comment? ;-)

As far as I know, there has only been one fatality as a result of a wire strike - and that was on a round.

- KidWicked
Coreece: "You sound like some skinheads I know, but your prejudice is with Christians, not niggers..."

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I would only change one thing on that tower Jump
With the 160 deg off heading, night before last.

I could be getting in to a bad Habbit ?

I don't think I will make a habit of doing
Toggle, back-up, reverse turns from a
Night time off heading Tower jump

As the Velcro was pealing from the toggle unstowing
I had a flash in my Brain of....
What if there was a line twist ???
But... I was past the point of no return.

Your reflex's work so fast. I did not visually clear that
possible problem before doing that maneuver.
plus its hard to see becouse it is Dark at night.

I have turned and corrected plenty of bad headings on Night Tower jumps with Risers only.

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general reply

you'll only hit a wire if you open above it. If you can't out track them, then pull below them..

;)



May we live long and die out

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pulling below the last Wire.
Yep the last wire at our Tower is 150 Feet.
That works for me.

I have never have or ever tried to stage deployment between
wires on a Tower jump.
To try to judge where & when to pull between the wires for added safety.
is not applicable and is a waist of time.

Maximum separation is priority # 1
the most important thing.

No matter how short or tall it is.

I just work on...
1. Getting as much separation as possible after exit.
2. Body positioning awareness.
3. Enjoying the Free-Fall.
4. Pulling at the height I decide to.
5. Fly away, Or do what it takes to fly away and land.
6. Go get a cold Beer.
* In that Order *

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appologies to Yuri for not saying thanks.
having always heard "wind down a wire is bad", the original post was an eye opener...

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Yuri is correct about these issues. There is only one subtle detail though that I've noticed when jumping in strong winds with the wind down the wire. First, on exit, you're basically working with a relative wind. I've noticed that my body sometimes will immediately point downwind or will 90 degree turn off that axis. I've also noticed that my canopy tends to open downwind, which can be down the wire if the wind is down the wire. The canopy seems to windsock.
Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

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Anyone with experience in wire strikes care to comment? ;-)



Yeah. Wires are pretty hard (if not impossible) to see at night. Don't count on being able to see one, and avoid it. And hope you don't get stuck. Canopies will re-open, but will hardly ever untangle themselves. Or so I hear.


Thomas

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Anyone with experience in wire strikes care to comment? ;-)





I've had one.

It was pretty much one of those "Your proctologist called, he found your head" manuevers, but I managed to clip the lowest guy while setting up a sub-optimal landing. It was dark out, I wasn't really paying attention to where I was quadrant-wise, and I never saw it until it was too late to avoid.

In my case I was lucky, the cells clipped the wire, I swung forward, the cells let go and surged in a stall. I hit the rears as hard as I could the instant before I hit the ground and rolled it out w/o injury.

If you jump As enough, particularly big ones, you'll wind up dancing with the wires at one point or another. :o

- Z
"Always be yourself... unless you suck." - Joss Whedon

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I've had a A/wire strike about three days ago, Dagger 240 and this was the 2nd 180 I've had on this canopy and actually the same A. I exited about 240' and pitched hand held. As soon as the dagger inflated I hammered the left rear to try to dodge the tower but my end cell struck. That collapsed my canopy long enough for me to sit fly until the guy wires decided they wanted to shred my 3 end cells, while still on the risers I managed to clear the 8' barbed wire fence by inches and my canopy landed guess where? other side of the barbs. I was fortunate enough to have the left side inflated to slow my decent rate enough to be able to walk away from that function. Anyone want to contribute to the new canopy fund or cell replacement fund I'm starting! LOL seriously though A's are the most dangerous objects to jump in my opinion given only 60 deg off heading to work with while you have the "perfect" wind. If your new to the sport In my humble opinion stick to twin fallls or accesible B's. If I would have climbed to the top of this A I probably wouldn't be posting this. Listed to Tom's advice I don't personaly know him but his physics is correct (BTW I have a BS in Math and Mech. Eng., working on Aeronotical).

live every day like its your last,

cap'n Xaos

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A's are the most dangerous objects to jump in my opinion given only 60 deg off heading to work with while you have the "perfect" wind.


but atleast you´ll always have the wind to carry you away from the Antenna itself,you will in most times just ned to imput some toogle input to clear it...(not on a 180 off a 240ft i know...)

Personaly i think A´s are in the safer range compared to B´s or E´s (talking low jumps)But thats just me,metalworker some wee in the world:P

Stay safe
Stefan Faber

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Mr. swOOPS don't take this as negative criticism.
This is just my way of showing positive reinforcement.
I dont mean to crawl up your ass about this.

I have looked at Antenna, guy wire close up and they look pretty mean.

SwOOPS.... Your first mistake was jumping a Dagger.
Not for the off-headings but it has shitty low air speed inflation qualities.
PLUS......
240 Ft. you will not get much of a response from that Bed Sheet your
flying, using the Rear Risers. on a Hand Held exit.
I really doubt that you could have turned it around enough.

Even your best canopy pilots using a quality vented canopy.
With a tuned deep brake setting.
Going Immediately to slamming the Toggles down and trying to crank
it around.
I guarantee that he would be sweating it a bit, to say the least, At 240 Ft.

Unless he had a Nice stiff, tail-wind splitting between the wires to help
him get good separation when the fabric started to deploy and stage
up for inflation.
Would be more in his favor but still very tight.

Also.... How do you think, You Qualify to be Free-Falling 240 Ft. with
your lack of BASE skills ...???????

Free-Falling 240 ft. does not sound like any big deal these days.
Unless you have a Problem.
Then its pretty F##king Major.
And being able to fly a high performance skydive canopy does not
mean jack-shit in the Sub-300 ft. free-fall world. Or for being able to
fly a BASE canopy.

Also.... Antenna are Not the most dangerous objects to jump.
You just did not play the game right.
That really shows your lack of BASE jumping skills right there.

But....good job on getting out of your situation and being able to talk
about it and hopefully learn from it.

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If your new to the sport In my humble opinion stick to twin fallls or accesible B's.



B's?

I would not suggest that at all.

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SwOOPS.... Your first mistake was jumping a Dagger.
Not for the off-headings but it has shitty low air speed inflation qualities.
PLUS......
240 Ft. you will not get much of a response from that Bed Sheet your
flying, using the Rear Risers. on a Hand Held exit.
I really doubt that you could have turned it around enough.



I have to agree here. I had a dagger266 and was jumping it down to around 210ft. The inflation problems I had with this meant I was getting pounded in quite alot from the lower freefalls (much to Fabers amusement once!). I had some pretty shitty off headings on some low jumps and the response to input with this lack of speedy inflation was sometimes a little hairy............... I went out and bought something else (troll MDV) and after jumping that never wanted to take my dagger below 300ft again.

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Also.... How do you think, You Qualify to be Free-Falling 240 Ft. with
your lack of BASE skills ...???????

Free-Falling 240 ft. does not sound like any big deal these days.
Unless you have a Problem.
Then its pretty F##king Major.
And being able to fly a high performance skydive canopy does not
mean jack-shit in the Sub-300 ft. free-fall world. Or for being able to
fly a BASE canopy.

Also.... Antenna are Not the most dangerous objects to jump.
You just did not play the game right.
That really shows your lack of BASE jumping skills right there.



not to be rude but how do you know anything about my base experience. No maybe I haven't reached 1000 yet but im rapidly approaching 150 which I know is not very many in this most dangerous sport but I have had many minor circumstances that could have ended fataly if not for my general canopy control. I currently fly a vengence 97 @ 2.0 and swooping barely past the peas at my local DZ. I have over 500 skydives which I also realize is not many but I have had people tell me I have better that average canopy control vs. jump #'s. BTW I am also a pilot, low hours but I could fly any skydiving aircraft if I cared to get the proper licences. I have had a passion for flight since I could walk and skydiving/BASE jumping has really come sort of natual to me. Im no competition ready gung ho junkie. I do these thing because I enjoy them, competing somewhat takes away from the enjoyment of any activity/sport I know cause of the high school sports I played. I don't log skydives nor base jumps cause all that is is some number, it represents no skill and I think USPA should not grant licences based on jump #'s and the measly prerequisites it takes to get them, they should have to prove skill in an entire skydive in front of some sort of instructor like AFF student do to get off student status. Sorry off the subj. a lil but my logbook is in my head and my video's and its doing a darn good job for me. I appreciate your concern but I feel I need a better vented canopy and maybe a new way to pack my rig. That was the 2nd 180 on the dagger in 40 jumps packed meticulously the same every time. Does anyone else have any comments on daggers and 180's. Also does anyone have a better canopy for sale in the 240-266 range because I prefer no slider jumps in the 200-300 range. My lowest to date was about 175 and I was open at 75 feet. I will try to beat 9-lives record of 79 feet in a couple of years/more jumps too, not any time soon though 250 is my comfort range as of this time. I have about 25 9-14 sec. delays off A's and don't get me wrong they are a blast but unless its got an Ele. or man lift forget climbing that far, im too lazy for that crap although mountain climbing cliff jumps would be more up my alley but in my vacinity there are ONLY A's & B's for probably 500 miles. After careful inspection of my canopy I only had 5 pressurized cells which is the only reason im walking/breathing/writing this reply today. Survival instincts kick in in those situations and I feel like I flew and landed the shreded canopy the only survivable way. God was definitely with me that night and I thank him for the way it turned out.

Thanks to all of you for your advice and feel free to send anymore this way, my mentors or should I say lack thereof havent covered everything but I have picked up most of what I need to know for A's and B's. id prefer if you would email me on my DZ.com account instead of posting unless you feel like everyone shouls hear it.

The dagger is my 2nd canopy, my first was a bruislight I mean cruiselite so I actually really liked the dagger except the 180's, it opened fast and on heading exactly 96% of the times I jumped it

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Sounds like you guys may have some previous background? Regardless, any differences you may have are personal, and best dealt with in some other place than this public forum.

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I currently fly a vengence 97 @ 2.0 and swooping...



It is a mistake to think these skills will have much bearing on BASE.

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I feel I need a better vented canopy...



If you are interested in low freefalls, a Dagger is definitely the wrong choice. Vertigo makes a canopy intended for these sorts of jumps called the Rock Dragon. You might also want to investigate the Blackjack, the vented Flik, and the Troll MDV.

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and maybe a new way to pack my rig...



How are you packing now?

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That was the 2nd 180 on the dagger in 40 jumps packed meticulously the same every time.



In my opinion, 40 jumps is an inadequate sample size to draw any conclusions about the canopy. In addition, there are many factors that are far more important to your opening heading than the canopy (things like body position and wind spring immediately to mind).

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My lowest to date was about 175 and I was open at 75 feet.



Freefalling 175 feet with either of the two canopies you mentioned (Cruislite or Dagger) is a huge mistake. I'd strongly urge you to hold off on that kind of thing until you have a canopy with bottom skin inlets.

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I will try to beat 9-lives record of 79 feet in a couple of years/more jumps too...



The lowest BASE jump I know of is 63'. You can see the video of this jump on Jason Bell's excellent "Fixed 2".

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...my mentors or should I say lack thereof havent covered everything but I have picked up most of what I need to know for A's and B's.



Just "picking up" things is probably not going to be the best way to approach building jumps.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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Also.... How do you think, You Qualify to be Free-Falling 240 Ft. with
your lack of BASE skills ...???????
......................................................


Hey...swOOPS
my apologies,
I honest did not mean to discredit your level of intelligence.
At times I can have a slight abrasive approach to communication.

I would like to rephrase ...Your Lack of BASE skills
..To.....
Enthusiasm and Thirst for Acquiring the Proper Knowledge and skills for.... Ground Rush.

I do have a honest concern for your over enthusiasm for the Ultra-Low BASE.
It is something that the majority of BASE jumpers go through.

The knowledge and the details of how to do, Low Free-Fall, is out for you to see.
a lot of qualified jumpers have already done the Ultra-Low, Free Fall.
Most of them will gladly share that knowledge with you.


When you cross that line and start free falling into the sub 300 ft.
That means 299 ft. or less
combined with exiting a object that is still behind you after opening.
Everything has to work out in your favor after you let go of the Pilot Chute.

If I did not like you I would not care.

Once again my humblest apologies.

....Raymond Losli

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