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Wind and Landing Direction

 

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Joeburnie

Oct 1, 2012, 1:13 PM
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Wind and Landing Direction Can't Post

Hi all,

I am a recently qualified skydiver and also a final year Product Design and Technology student. I have recently been trying to identify various problem areas for my final year project. Something I have been thinking about is a device which would make it clearer to a skydiver as to what the ground winds are doing so they can set up for landing properly. The problem being that the ground wind direction can change when the load is in the air and the upper winds can be different to the lower winds. At the airfield I jump at the landing pattern starts at 1500ft and the downwind leg begins at 1000ft even from a height of 1000ft it is difficult to see the wind socks.

The potential product would make it clear to the parachutist which direction the ground winds are blowing meaning it would be clear in which direction the landing pattern should be started.

I've spoke to some experienced jumpers at my DZ and they were sceptical of the idea but I'm not quite ready to put it to bed yet!

I'm looking for some feedback / comments off other skydivers and possibly some instructors opinions on whether it is a good idea to use for students?

All comments welcome but you must understand that they may be used in my final year project which may be on public display, although you will not be identified in any way.

Thanks,
Joe.


AggieDave  (D License)

Oct 1, 2012, 1:26 PM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

They invented those a very long time ago and called them tetrahedrons.

http://farm1.static.flickr.com/...12404_f44d615627.jpg

At my old (and now closed) DZ, we had one as well as a windsock. You could see the big triangle pointing the way from 5k with no problem. Although we did have to tell new jumpers (to the DZ) "eat the carrot, follow the arrow" after we had a few rocking downwinders from low time jumpers.Laugh


CarpeDiem3  (D License)

Oct 1, 2012, 1:29 PM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

Build a tetrahedron.


wolfriverjoe  (A 50013)

Oct 1, 2012, 1:33 PM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

Some DZs establish landing direction prior to takeoff. That isn't changable no matter what the winds do (this is at DZs where a radical windshift is not a normal occurrence).

There are several other WDIs. The "Wind Tee" (aka the "little airplane") and the "Tetrahedron" are the two most common.

There's also the "Really, really big windsock." I've seen them 15ft +. Those are not hard to see from pattern entry altitude.

I've heard of , but not seen, a large arrow, that is movable and lockable. It won't necessarily move with the wind, but can be put into place and locked there to indicate pattern direction (again, some places don't want the pattern to change even if the wind does).

Good luck. I have a funny feeling you are trying to reinvent the wheel, but that doesn't mean you can't or won't come up with a good idea.

Edit to add pic of sock, tee and tetra.

http://www.google.com/...sQ9QEwAw&dur=171


(This post was edited by wolfriverjoe on Oct 1, 2012, 1:36 PM)


CygnusX-1  (B 28761)

Oct 1, 2012, 2:31 PM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

The problem with tetrahedrons are that they are big and take a lot of wind to move them. I would suggest coming up with either a motorized tetrahedron or maybe one made of a grid of lights that would display an arrow and make it all electronic controlled by a small anemometer.

That way all the noobs can set up their landing direction to land into the wind when there is a 0.25 knot wind blowing.Crazy


AggieDave  (D License)

Oct 1, 2012, 2:50 PM
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Re: [CygnusX-1] Wind and Landing Direction [In reply to] Can't Post

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The problem with tetrahedrons are that they are big and take a lot of wind to move them.

The benefit of tetrahedrons is that they don't change with every minor gust of wind in a different direction. They hold to the dominate wind.

The ones I've seen usually move around 3-5kts and really under that any skydiver should be able to land downwind or crosswind with zero issues. If they can't then they need to seriously address their lack of canopy control skills.


theonlyski  (D License)

Oct 1, 2012, 2:56 PM
Post #7 of 39 (2902 views)
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Re: [CygnusX-1] Wind and Landing Direction [In reply to] Can't Post

In reply to:
The problem with tetrahedrons are that they are big and take a lot of wind to move them. I would suggest coming up with either a motorized tetrahedron or maybe one made of a grid of lights that would display an arrow and make it all electronic controlled by a small anemometer.

That way all the noobs can set up their landing direction to land into the wind when there is a 0.25 knot wind blowing.Crazy


OOOOH, Howabout an ALS?Tongue

The tetrahedron works well, if it is light and variable wind, you can weight it down and keep everyone landing in a safe direction.


(This post was edited by theonlyski on Oct 1, 2012, 3:04 PM)


Premier billvon  (D 16479)
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Oct 1, 2012, 4:26 PM
Post #8 of 39 (2840 views)
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Re: [CygnusX-1] Wind and Landing Direction [In reply to] Can't Post

>The problem with tetrahedrons are that they are big and take a lot of wind
>to move them.

Those are two reasons that they are a _good_ thing to have.

> I would suggest coming up with either a motorized tetrahedron or maybe
>one made of a grid of lights that would display an arrow . . .

"Did you set the tetrahedron direction for the first load?"
"oops!"

>and make it all electronic controlled by a small anemometer.

Wouldn't that be like a $1000 wind sock that needs lots of power?


craigbey  (C 31991)

Oct 1, 2012, 5:15 PM
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Re: [AggieDave] Wind and Landing Direction [In reply to] Can't Post

Quote:
The tetrahedrons I've seen usually move around 3-5kts and really under that any skydiver should be able to land downwind or crosswind with zero issues. If they can't then they need to seriously address their lack of canopy control skills.

Wait ... we're not supposed to chase the wind sock?


brewster71

Oct 1, 2012, 5:21 PM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

Dunno what you'd do here. In Alberta I've had 30 kph wind switch from east to west from 500 to 300ft. nothings perfect, just gotta get good at cross wind landings here i guess :) good luck with your prodject!
In reply to:


theonlyski  (D License)

Oct 1, 2012, 5:44 PM
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Re: [billvon] Wind and Landing Direction [In reply to] Can't Post

In reply to:
Wouldn't that be like a $1000 wind sock that needs lots of power?

Could probably make one for a few hundred bucks, make it solar power even... But that would be trying to fix a problem that doesn't really need fixin'.


hokierower  (B 36150)

Oct 1, 2012, 6:14 PM
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Wind and Landing Direction [In reply to] Can't Post

Only thing that i can think of would be a series of lights arranged in a circle that would be controlled by a small weather station. The lights would light up towards whatever direction the wind was coming from and the velocity of the wind would control how quickly they light up. Throw in some sort of a daily calibration test. You'd have to go with some pretty powerful LEDs to make it visible though. The devil would be in the code because to be viable you'll have to write the program so that it takes the average speed for the past minute or five minutes, etc, so you don't have any issues during light and variable days.


AggieDave  (D License)

Oct 1, 2012, 6:33 PM
Post #13 of 39 (2747 views)
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Re: [hokierower] Wind and Landing Direction [In reply to] Can't Post

In reply to:
Only thing that i can think of would be a series of lights arranged in a circle that would be controlled by a small weather station. The lights would light up towards whatever direction the wind was coming from and the velocity of the wind would control how quickly they light up...

What about 100 50" LCD TVs laid flat in a large square configuration, so that the screens are pointed up. Then you can control it via a computer interface to display landing direction, wind speed and other important landing information like "HOOK IT YOU PANSY" and the like. Of course some sort of weather proof housing would have to be constructed, which would have to be cleaned daily due to bird droppings and skydiver's muddy feet.

You could also use it for AFF canopy flight: "Turn left, no not you, the other guy with the beard...no, your other left, no, left...damnit, well turn that way again and you'll be pointed the right direction." I'm sure some sort of new process would have to be developed to help the students flare at the right height. For that we might need to add a large outdoor sound system to loudly project "WAIT, NO WAIT FOR IT, NOT YET, WAIT FOR...DAMNIT, OK PLF LIKE YOU MEAN IT!"

This new system has merit and could be the new industry standard to replace all of those cheap windsocks and tetrahedrons. I'm sure we could build this for $250k if we could toss BillVon some stale bread so he could quack us up some computer stuff.


davelepka  (D 21448)

Oct 1, 2012, 6:48 PM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

Quote:
The problem being that the ground wind direction can change when the load is in the air and the upper winds can be different to the lower winds. At the airfield I jump at the landing pattern starts at 1500ft and the downwind leg begins at 1000ft even from a height of 1000ft it is difficult to see the wind socks.

Take this observation constructively, but all you have identified is a problem that you have, as a new licensed jumper at that one DZ.

The reason the more experienced jumpers are skeptical is that they don't have the same problem, and in turn are not looking for a solution.

If you jumped at another location, you might find that their wind indicator might be clearer to you, and then you would no longer have a problem.

Truth is, if you really have a problem, set up some flags or a windblade to supplement the wind sock at your current DZ, and you have a fool-proof solution for very little money (under $100). Alternatively, you could look into a larger or brighter colored windsock. They usually start off neon orange, but that will fade over time, so you might find that a 'fresh' one will be easier to spot.


shorehambeach  (B License)

Oct 2, 2012, 3:28 AM
Post #15 of 39 (2641 views)
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Re: [AggieDave] Wind and Landing Direction [In reply to] Can't Post

In reply to:
They invented those a very long time ago and called them tetrahedrons.

http://farm1.static.flickr.com/...12404_f44d615627.jpg

At my old (and now closed) DZ, we had one as well as a windsock. You could see the big triangle pointing the way from 5k with no problem. Although we did have to tell new jumpers (to the DZ) "eat the carrot, follow the arrow" after we had a few rocking downwinders from low time jumpers.Laugh

+ 1

As a low number jumper - I went to a new dz and they had one instead of a wind sock - IMO much better as they give the dominant wind direction rather than constant variable it tends to be on the ground.

A GREAT invention (as a newbie) would be an automated PACKING machine ;)

Tongue


danornan  (D 11308)

Oct 2, 2012, 4:36 AM
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Re: [shorehambeach] Wind and Landing Direction [In reply to] Can't Post

Wind direction is fine if you are the only one landing. If not, the best direction to land might not be directly into the wind. I have watched people die chasing a wind sock or hooking it so as to land directly into the wind!

Be predictable and land the way that everyone else is landing, hopefully in the pattern.

Wind direction is only a guide and not an absolute.


Joeburnie

Oct 2, 2012, 5:13 AM
Post #17 of 39 (2601 views)
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Re: [All] Wind and Landing Direction [In reply to] Can't Post

  I've heard of tetrahedrons and also I've heard of airfields manually setting out big arrows pointing in the landing direction. One criticism from an experienced jumper I spoke to was exactly that - people got confused about whether they were "eating the carrot" or "following the arrow" and some ended up "following the carrot" and "eating the arrow!"... Although I'm sure a proper brief before jumping would alleviate the problem.

Some skydivers have started using GPS on their jumps now, am I right to assume the GPS is built into their altimeters? What if the wind speed and direction was displayed either on the altimeter itself or on a separate device on the skydiver's person?

Thanks again,

Joe.


chuckakers  (D 10855)

Oct 2, 2012, 5:38 AM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

Easy - over-sized tetrahedron positioned by servo motors guided by a sensitive wind indicator. Add a manual over ride for no-wind days and a control unit to keep it from displaying erratically in wavering winds and you're there.


Premier Remster  (C License)

Oct 2, 2012, 5:43 AM
Post #19 of 39 (2582 views)
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Re: [AggieDave] Wind and Landing Direction [In reply to] Can't Post

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What about 100 50" LCD TVs... <snip>

Winner!


theonlyski  (D License)

Oct 2, 2012, 6:24 AM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

In reply to:
Some skydivers have started using GPS on their jumps now, am I right to assume the GPS is built into their altimeters?
Nope, usually they're using a separate GPS unit.

In reply to:
What if the wind speed and direction was displayed either on the altimeter itself or on a separate device on the skydiver's person?

Well, that would work great for determining a few parts about your canopy flight, however (AFAIK) it's not possible for the unit to determine wind speed and direction without having to fly in every direction so it can calibrate. Then you gotta remember, winds shift/change from what they were at 6k to what they are at 3k and even what they are at the ground.


CarpeDiem3  (D License)

Oct 2, 2012, 7:15 AM
Post #21 of 39 (2527 views)
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Re: [shorehambeach] Wind and Landing Direction [In reply to] Can't Post

In reply to:
Re: tetrahedrons.
I went to a new dz and they had one instead of a wind sock - IMO much better as they give the dominant wind direction rather than constant variable it tends to be on the ground.

And if the wind sock is limp, instead of everyone landing willy-nilly every which way they want, the tetrahedron keeps things safe by giving everyone a uniform direction to land in.


CarpeDiem3  (D License)

Oct 2, 2012, 7:23 AM
Post #22 of 39 (2519 views)
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

In reply to:
Some skydivers have started using GPS on their jumps now, am I right to assume the GPS is built into their altimeters? What if the wind speed and direction was displayed either on the altimeter itself or on a separate device on the skydiver's person?

Measuring the wind speed under canopy with something like an anemometer wouldn't work, since airspeed is constant no matter what direction you're facing relative to the wind.

So you would have to use GPS and calculate wind speed as a function of how fast you're moving across the ground. And that would have to take into account the canopy speed. I.E. ground speed minus canopy speed = wind speed. And that would apply only if you're running downwind. If you're facing into the wind, then ground speed PLUS canopy speed = wind speed. So now you've got to have both a GPS and an anemometer, coupled together with some electronics.

And determing wind direction would require that you turn a 360-degree circle so it can calculate which way produces the fastest ground speed, in order to know the wind direction.

Gonna be complicated...


(This post was edited by CarpeDiem3 on Oct 2, 2012, 7:27 AM)


Joeburnie

Oct 2, 2012, 7:30 AM
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Re: [theonlyski] Wind and Landing Direction [In reply to] Can't Post

Quote:
Well, that would work great for determining a few parts about your canopy flight, however (AFAIK) it's not possible for the unit to determine wind speed and direction without having to fly in every direction so it can calibrate. Then you gotta remember, winds shift/change from what they were at 6k to what they are at 3k and even what they are at the ground.



Regardless of how the system would work (let me worry about that) do you think a product which informed the parachutist of ground wind speed and wind direction, when at height, would be useful? This is the type of product I had in mind but I'm trying to identify the problem before I come up with the solution.

Cheers again,


Joe.


theonlyski  (D License)

Oct 2, 2012, 7:33 AM
Post #24 of 39 (2510 views)
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

In reply to:
Regardless of how the system would work (let me worry about that) do you think a product which informed the parachutist of ground wind speed and wind direction, when at height, would be useful? This is the type of product I had in mind but I'm trying to identify the problem before I come up with the solution.

No, I don't think it would make a difference to anyone. It's easy to look down and say "I'm hauling ass" or "I'm not getting any forward progress". No need for any electronics to tell us what our MK-1 eyeballs are already able to tell us.

You're trying to identify and fix something that isn't a problem.


Premier Remster  (C License)

Oct 2, 2012, 7:33 AM
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Re: [Joeburnie] Wind and Landing Direction [In reply to] Can't Post

Quote:
do you think a product which informed the parachutist of ground wind speed and wind direction, when at height, would be useful?

Useful? Yes, I suppose.

Would I pay more than $0.50 for it, when I can get that information from a windsock and tetrahedron and pre-jump observations? Nope.

I guess this is the inevitable progression of swooping by audible.... Unsure


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