look first

[happythoughts 0]

Scenario: You are flying into a little wind. You are at 2000 ft. You want to drop down a little with a spiral. Where do you look?


Behind you. That is where you are going to be.

As you start the turn, you will run with the wind a little. When you finish the turn, you will be lower and a little behind where you were.

Look to the sides, look below, but look behind you also.

[jheadley 0]

hmm... I can see you being behind where you were before relative to the ground, but relative to other canopies that are also in the sky, I don't think it'd change.

Edited again... I'm trying to figure out how to say this in a way that isn't confusing. Relative to the ground, the wind may have an effect on you, but relative to other canopies in the air, it will not.

However you are correct that you will be "behind" where you were after a 360, but I believe just because of the forward speed of your parachute, and the forward speed of a parachute that is behind you, and flying on the original heading. Wind doesn't have anything to do with this.

I'll stop now, my head hurts.

[Ms.sofaking 0]

If someone was lower and holding behind you, isn't that right where you'd end up?

"I'm not sure how it's going to turn out, except I'll die in the end, she said. So what could really go wrong? -----Brian Andreas

[billvon 2,683]

>You are flying into a little wind.

>Where do you look?

Around and below. The wind doesn't matter.

[Ms.sofaking 0]

so not behind?

"I'm not sure how it's going to turn out, except I'll die in the end, she said. So what could really go wrong? -----Brian Andreas

[yeyo 1]

looking 'around' includes left, right, front, and behind

HISPA #93
DS #419.5

[tdog 0]

I call foul...

Unless there are different wind speeds or directions at your altitude relative to the altitude below you... All the canopies will fly in the airstream equally... So wind speed won't matter...

Example. Two 747 airplanes are flying in 200 MPH winds because their crazy pilots like flying thru hurricane force winds. Both planes are at full throttle and are flying at 500 MPH air speed. If heading opposite directions, parallel to the direction of the wind, one airplane will have 700 MPH ground speed. The other 300. But if they were to collide headon - their collision speed would be 1000 MPH.... (500 + 500 airspeed, or 300 + 700 ground speed).

No where does the wind speed change the speed in which the aircraft will collide or the closing speed of the aircraft. (Unless each aircraft is in a different moving body of air that has different speed or direction).
So... Please tell us how you will "run with the wind", relative to another canopy, as you start your turn...

[happythoughts 0]

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However you are correct that you will be "behind" where you were after a 360, but I believe just because of the forward speed of your parachute, and the forward speed of a parachute that is behind you, and flying on the original heading. Wind doesn't have anything to do with this.

In a zero wind situation, you might just turn in place.

In a 15mph wind, do a quick turn. You don't run with the wind as far. Then, do a slow turn that causes you to run with the wind a little longer.

In a 15mph wind, a big canopy may be parked behind you and you drive back to it. A faster canopy may drive under you.

Lots of possibilities.

This can be an intellectual exercise and eventually lose the point.

I was having this conversation last weekend about an experience. The time that someone didn't look back at 1000ft, they were above and in front of me.

They spiraled right in front of me and never saw me, yet missed me by 80ft.

This is one of the two reasons that I am against people spiraling near the pattern. The other reason is all the people who have hooked other people out of the sky recently, and in past memory.

[happythoughts 0]

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All the canopies will fly in the airstream equally... So wind speed won't matter...

Please tell us how you will "run with the wind", relative to another canopy, as you start your turn...

First off, I've never flown a 747. Whatever they do is of no interest. I was discussing flying my canopy.

We are talking about flying your canopy over a little spot of ground. If someone is in that little spot and you drive over them, you collide.

Relative starting/ending positions in reference to the ground and altitude.

Real example.

Two canopies are facing into a 20mph wind, you may have no movement, relative to the ground.
One is 300 ft behind and 200 ft below the first.

If they stay static, they may just sink slowly and land 300 ft apart. Zero ground speed.

If the one in front makes a slow 360 degree turn, he may end up in a position 300ft back from his original position. In turning, he will lose altitude (maybe 200ft). He is now occupying the same spot as the other canopy who has not moved.

My canopy covers a huge amount of ground when traveling in the same direction as the wind. I call this "running with the wind". Probably 40mph sometimes.

I know that you can tell the difference when coming back from a long spot with a 20mph tail wind or 20mph head wind. Can't you?

[tdog 0]

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We are talking about flying your canopy over a little spot of ground. If someone is in that little spot and you drive over them, you collide.

Yes - if you are flying next to a radio antenna and you are making a turn, you will "run with the wind" into the antenna faster when you are downwind.

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Two canopies are facing into a 20mph wind, you may have no movement, relative to the ground.
One is 300 ft behind and 200 ft below the first.

If they stay static, they may just sink slowly and land 300 ft apart. Zero ground speed.

If the one in front makes a slow 360 degree turn, he may end up in a position 300ft back from his original position. In turning, he will lose altitude (maybe 200ft). He is now occupying the same spot as the other canopy who has not moved.

Yes, you will in this case fly around the other canopy - but the distance between that canopy and you will be exactly the same in 0 and 30 MPH winds... Your position over the ground however will be vastly different.

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I know that you can tell the difference when coming back from a long spot with a 20mph tail wind or 20mph head wind. Can't you?

Yes... When I am flying next to my friends doing CrEW in 80 MPH uppers, or in the 20 MPH winds at 2,000 feet, or 5 MPH winds at landing - our ground speed changes. However, I pull the exact same toggles or risers to fly relative to them. Windspeed does not change at all how I fly to get back to, behind, above, in front of, or next to my friends... If I was going to collide with them in 80 MPH winds, I would collide with them in 0 MPH winds... Where I need to look for them does not change - unless they are tied to the ground like a kite or a BASE jumper who has not left the antenna yet...

[RJmoney 0]

if there are 80 mph winds and you spiral down and run into me when im on antenna, im gonna be really freakin pissed.
i mean what the heck, seriously.

word to your mother,
RJ$$
BASE 1117

[jumpnaked69 0]

Now i'm not a scientist but it seems like the 40mph your canopy would cover is whats known as ground speed, or your canopy's speed relative to the ground. Your canopy's airspeed at any given time it is in full flight (that's toggles all the way up and no input on the risers) is a consistent speed (let's call it 20mph for the sake of simplicity). If you're flying into a 20mph wind, your airspeed is still 20mph but your ground speed is 0. If you're running with the wind doing 20mph and your canopy is already doing 20mph then simple math says you're doing the 40mph (although that's not technically accurate).

Now if someone is directly below you and you do a 360, you're much more likely to end up behind them than colliding with them. The reason is that their canopy continues to fly straight (assuming they have not done anything to affect canopy flight) and yours is essentially spiraling over that same relative spot.

[jumpnaked69 0]

i dont think there'd be anything sweeter than for tdog to jump just before RJMoney, catch some wicked thermals, and end up back on the antenna ready to go again.

[happythoughts 0]

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Now if someone is directly below you and you do a 360, you're much more likely to end up behind them than colliding with them. The reason is that their canopy continues to fly straight (assuming they have not done anything to affect canopy flight) and yours is essentially spiraling over that same relative spot.

Yes, that is exactly what I am saying. It is a person who is behind you and below you that is in danger.

That is whole point of the thread. That is why I stated in the first post, we need to look BEHIND AND BELOW us when spiraling. (Not only those places, but they are the most neglected. Look everywhere.)

A ground speed of 0 mph (similar to being tied to one spot) is easily achieved. (A 200sq ft canopy facing into
a 15mph). They are parked in one spot.

If you have a strong headwind and do a 360 spiral, you will always lose ground position. You will now be farther downwind than when you started.

The person behind you may be in danger.

[jumpnaked69 0]

well i think you might still be missing the point tdog and i trying to make about the differences in ground speed and airspeed. that person is in danger regardless of the strength of the wind--ya dig? while i think we should look all around us (to include behind although that's physically a bit difficult and maybe impractical) it has nothing to do with the wind conditions. your canopies will fly the same in the same conditions....

[pilotdave 0]

Your point is fine... when we spiral, we effectively stop moving horizontally through the air and effectively move straight down through the air. The guy below and behind you could be on a collision course. Look down and back before spiraling.

But wind has nothing to do with it, so don't convolute the advice. It makes no difference which way the wind is blowing. It's about the relative position of the two canopies within the air mass. You'll get closer to someone flying below and behind you when you spiral, period.

If two people are walking on a sidewalk, one in front of the other, and the guy in front decides to start walking in circles, the guy behind will get closer and could hit the guy in front. Same applies to two ants walking on a treadmill. The speed of the treadmill or the direction they're walking on the treadmill makes no difference to whether or not the ants will run into each other.

Dave

[jumpnaked69 0]

yeah, what he said.

[happythoughts 0]

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well i think you might still be missing the point tdog and i trying to make about the differences in ground speed and airspeed.

From above:
"This can be an intellectual exercise and eventually lose the point."

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that person is in danger regardless of the strength of the wind--ya dig?

That was the actual point of the thread.

It wouldn't make me feel any better if someone dies in a different spot because their ground speed was different.

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while i think we should look all around us (to include behind although that's physically a bit difficult and maybe impractical)

Thanks, that makes my second point.
Knowing the difficulty, it becomes a good guideline that people should not spiral near any congested areas.
It is best to do it where other people "probably aren't".

People don't intentionally collide with others.
Let's try to keep the people safe that they don't see with a little forethought.

(That's pretty much all I have to say. People can correct my grammar now. )

[jakee 1,319]

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I was having this conversation last weekend about an experience. The time that someone didn't look back at 1000ft, they were above and in front of me.

They spiraled right in front of me and never saw me, yet missed me by 80ft.

The result would have been exactly the same if you had both been running, holding, crabbing, crosswind, nil wind....

Do you want to have an ideagasm?

[popsjumper 2]

Bill,
Thanks for the simple message. Too, bad it's getting lost in all the hypothetical and theoretical scenarios.

OTOH, those scenarios are providing some learning opportunities by raising questions. I'll get with Scott Miller or Brian Germain to resolve them.

My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239