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el_chester

Upper winds in opposite direction to lower winds

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I once had a discussion on this with a friend, who stubbornly said this was impossible, because according to him, all air moves together in the same direction.

Today from the window of one of the places I work at, I shot this time-lapse movie which -to my surprise- gave me the evidence I needed to convince that friend.

Video here.

So my point is... if you are not too experienced, don't assume you always have to land in the direction of the jump run, there are times when to land into the wind, you have to turn 180 degrees from the direction the plane was travelling when it dropped you, assuming it was a jump run into the wind (like most are).

Always watch the wind at ground level and -unless DZ landing direction rules mandate otherwise- set up your pattern accordingly. (The only slight injury I have had skydiving was hurting my heels while running out a downwind landing @ 5000ft ASL.)

--
Be careful giving advice. Wise men don't need it, and fools won't heed it.

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I once had a discussion on this with a friend, who stubbornly said this was impossible, because according to him, all air moves together in the same direction.

Today from the window of one of the places I work at, I shot this time-lapse movie which -to my surprise- gave me the evidence I needed to convince that friend.

Video here.

So my point is... if you are not too experienced, don't assume you always have to land in the direction of the jump run, there are times when to land into the wind, you have to turn 180 degrees from the direction the plane was travelling when it dropped you, assuming it was a jump run into the wind (like most are).

Always watch the wind at ground level and -unless DZ landing direction rules mandate otherwise- set up your pattern accordingly. (The only slight injury I have had skydiving was hurting my heels while running out a downwind landing @ 5000ft ASL.)



Cool.

Happens quite a lot around the Great Lakes.
...

The only sure way to survive a canopy collision is not to have one.

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I once had a discussion on this with a friend, who stubbornly said this was impossible, because according to him, all air moves together in the same direction.

Today from the window of one of the places I work at, I shot this time-lapse movie which -to my surprise- gave me the evidence I needed to convince that friend.

Video here.

So my point is... if you are not too experienced, don't assume you always have to land in the direction of the jump run, there are times when to land into the wind, you have to turn 180 degrees from the direction the plane was travelling when it dropped you, assuming it was a jump run into the wind (like most are).

Always watch the wind at ground level and -unless DZ landing direction rules mandate otherwise- set up your pattern accordingly. (The only slight injury I have had skydiving was hurting my heels while running out a downwind landing @ 5000ft ASL.)



Yeah I already broke my ankle from that exact problem. SO tell your friend it is possible!!B| I didnt understand it when my instructor told me the winds up high were coming out of the north. He told me not to drift too far south so I didnt but when I went to land I was down wind and I was moving fast. I tried to stand it up instead of PLF and broke the left ankle.
Thankfully I didnt need surgery and the healing went well.
A hard lesson learned for sure but it definitely made me obsess over canopy control, canopy saftey and landing procedures and having a landing plan before I get onto the plan so something good came out of it.

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Just don't ask Van Pray at Cal City for a jumprun course correction out of the 206 when you are "splitting the difference" between the uppers and lowers, and you are getting "pushed" .2, .3, .4, .... .5 laterally off course of center, to "work" the spot. :P

Actually differences in upper winds versus ground winds is QUITE COMMON! If unsure, ask your jump pilot for the winds aloft report they get from flight services. You might just be surprised!
coitus non circum - Moab Stone

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>there are times when to land into the wind, you have to turn 180 degrees
> from the direction the plane was travelling when it dropped you, assuming
> it was a jump run into the wind (like most are).

This is also the worst case when it comes to exit separation. If the winds are opposite of jump run winds, give whatever time you'd give for the normal uppers - then add 20%.

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You can get both values almost instantly: Upper wind speed and direction can be calculated comparing airspeed with ground speed. The aircraft GPS asks for heading, temperature and altitude and outputs wind speed and direction. The pilots can ask air controllers for ground wind speed and direction. They differ quite often.

BTW. At our DZ, we are all supposed to follow the same landing pattern followed by the first skydiver landing. If S/he fails going into the wind that means BEER! ;)
Gonzalo

It cannot be done really means I do not know how to do it ... yet

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You might want to keep in mind that winds tend to veer(clockwise change in direction) and increase with increase in altitude.

Pressure changes as well as the Coiorlis force (caused by the earths rotation) affect the movement of air.

The wind close to the ground is slowed by friction. When the wind is slowed by friction such as trees etc. the coriolis force is less because it is directly related with the wind speed. The pressure change force takes over, and the wind will want to blow from high to low.

Since air rotates around a high pressure system clockwise, it will deflect to the left to the lesser pressure area. Vise versa with a low.

Also be careful with inversions. Temperature increase with altitude.
One type of inversion usually happens during sunset and at night time. The ground begins to cool a lot faster than the air above it. Resulting in really light winds on the ground and fast winds aloft.

So.
If doing a sunset load on a clear evening, the upper level winds can be a lot stronger and coming from a different directions than the ground winds.

It's always a good idea to ask the pilot what the upper level winds are up to.



[]DETE

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Is your friend that sheltered? I thought this was common knowledge, beyond skydivers and pilots.
"Any language where the unassuming word fly signifies an annoying insect, a means of travel, and a critical part of a gentleman's apparel is clearly asking to be mangled."

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we all know that wind is actually static, and it's the earth that revolves inside the atmosphere, thus creating a regular wind along the planet and some turbulence behind the mountains :|

and the Earth revolves thanks to An-2's:|
scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

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I once had a discussion on this with a friend, who stubbornly said this was impossible, because according to him, all air moves together in the same direction.

Today from the window of one of the places I work at, I shot this time-lapse movie which -to my surprise- gave me the evidence I needed to convince that friend.

Video here.

So my point is... if you are not too experienced, don't assume you always have to land in the direction of the jump run, there are times when to land into the wind, you have to turn 180 degrees from the direction the plane was travelling when it dropped you, assuming it was a jump run into the wind (like most are).

Always watch the wind at ground level and -unless DZ landing direction rules mandate otherwise- set up your pattern accordingly. (The only slight injury I have had skydiving was hurting my heels while running out a downwind landing @ 5000ft ASL.)



The airshow I work at has an annual hot air balloon festival in Aug. The pilots only way to steer is by finding different wind directions at different altitudes. A few years ago we were doing afternoon flight on what was a very calm day. By working the slight winds from ground to ~1500' they were slowly circling the airport!! Most were landing back at their launch site. If you have ever worked with HA Balloons, this was just WRONG! (And, no, they weren't tethered.)

So, can winds be 180 off at different altitudes, YUP!
Always remember that some clouds are harder than others...

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This is also the worst case when it comes to exit separation. If the winds are opposite of jump run winds, give whatever time you'd give for the normal uppers - then add 20%.

Ok and can you tell me how to figure 20% looking out the door of a plane . I am just wondering. This helped me a lot with it
Never give the gates up and always trust your rears!

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This is also the worst case when it comes to exit separation. If the winds are opposite of jump run winds, give whatever time you'd give for the normal uppers - then add 20%.

Ok and can you tell me how to figure 20% looking out the door of a plane . I am just woundering



If the plane is moving at constant speed (very likely on jumprun) you could add 20% to the distance you're looking for.
...

The only sure way to survive a canopy collision is not to have one.

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>Ok and can you tell me how to figure 20% looking out the door of a plane.

If you are going to wait 5 seconds, wait 6.

If you are going to wait 8 seconds, wait 10.

If you are going to wait 10 seconds, wait 12.

If you are going to wait for 1000 feet, wait for 1200.

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We experienced these conditions at our DZ on the weekend.. winds from the north from the top right down to about 1500ft (jumprun to the north obviously). Wind below 1500ft were from the south, very weird trying to set up a landing pattern in that - took me a bit to get my head around it on the ground before my jump (after discussing with other jumpers and the pilot)!! I was last out and left lots of time (10 secs) before i climbed out (i was opening high).

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