How to spread traffic over the dz,...

[Bartje 0]

How to spread traffic over the dz,

due to trafic over the dz there are accidents.
One way to avoid accidents is to spread the traffic.
This is not so easy because the time that canopies open is more or les the same time that skydivers need to exit the plane, even less because the fast freefallers are exiting as last due the current safety rule.
Would't it be more safe to let exit the fast freefallers first so the time needed for everybody to open his parachute is longer and as well the time that parachutes are landing?
The argument now is that the fast freefallers(FreeFly) exit last because there is a possibbility for an in air collition.
Often the FreeFlyers has faster canopies that the other skydivers and will be faster back to the ground even when they exit after the not so fast FreeFallers.

Now in France they changed the rule last year. On a windy day the FreeFlyers exit last, when there is not much wind or no wind at all the FreeFlyers exit first, during those days the traffic is well spread and much safer than on windy days.

I like to know your opinion for this French rule and as well new ideas to spread the traffic.

Greetz

Bartje

A FreeFly Gypsy

[cvfd1399 0]

Run the program that kallend(sp hurry) has sometimes you can get away with the exit order that you speak of due to the winds, but for the most part you are opening less than 50-100 feet of seperation with most times the jumpers cross over each others own "airspace" that extends above them and below them commonly called the "tube or pipe". If one were to cork have a premie, or freak out and deploy early you could have a freefall, or canopy collision.

[Bartje 0]

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If one were to cork have a premie, or freak out and deploy early you could have a freefall, or canopy collision.

Thats the biggest argument for the current safety rule at the moment. It works to avoid in air collitions but it do not work for enlarging the time in between opening from the first canopy and the last canopy and it is not safe at all with fast canopys wich have to exit and open after the slow canopies.

Fast FreeFallers (FreeFlyers) jump smaller groups than other disciplines but ofter fly faster canopies.

btw, I think that the program does not include the parameter for the surface from a freeflyer to the horizontal wind, is there anybody who has more details from this program?

A FreeFly Gypsy

[cvfd1399 0]

Sorry I was in a hurry this morning, so I could not spend alot of time to think and write a whole lot. From my experience using the program to put everything in view this is how it went. Using the wind speed settings that are commonly found every weekend at my dz most of the time when slow jumpers exited the plane first the seperation at opening time was usually over 800-1000 feet. When I had the fast fallers exit first the seperation during freefall looked good at first, then shortly before opening the fast faller either came close, or suceeded in crossed over the top of the slow faller resuting in opening seperation of 80-140 feet. That is with normal winds, if you play with it and put combinaitons such as; very high uncommon upper wind speeds, change the jump run from upwind to downwind or things like that you can make the program show that it is actually better to have the fast fallers go out first. This is is what I got when I played with it. I am still struggling to grasp all the different variables and put them together to make complete sense of the subject

[Bartje 0]

A possible solution for spreading the traffic would be to drop downwind with the fast freefallers exits first or upwind with a minimum distance of 2000ft.

Anybody?

A FreeFly Gypsy

[cvfd1399 0]

What is your main goal to increase opening or freefall seperation? It sounds to me like you are tired of comming up short and want to get out first for a better spot (joking)

[kallend 1,625]

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A possible solution for spreading the traffic would be to drop downwind with the fast freefallers exits first or upwind with a minimum distance of 2000ft.

Anybody?

Downwind would work for separation, but would give the plane very little time on jumprun** so that climbouts would be hurried. In addition, it does not change the "forward throw" factor. I think most people would find spotting difficult on a downwind jumprun.


** example - if the "window" over the DZ for an acceptable spot is 2 miles in length, then an Otter flying into strong uppers may take 2 minutes on jumprun, allowing all groups plenty of time to climb out and leave acceptable separation. Flying downwind in the same wind would only take 40 seconds, in which time all groups have to climb out and exit, and an error of just a few seconds could easily place you way outside the landing area.

Crosswind jumpruns are fine.

...

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

[Bartje 0]

the goal is to increase opening seperation,

No joke at all, The last 3 years I did see too many accidents due to havy traffic over the landingzone.

A FreeFly Gypsy

[Bartje 0]

So perhaps it is better to do the drop in two runs, one run for the fast and one run for the slow.

A FreeFly Gypsy

[cvfd1399 0]

In a perfect world we would have escort fighters protecting the airspace from planes and other flying creatures as everyone in the plane gets their own pass on jumprun. I read stories all the time here of people that want or wanted a go aroud b/c jump run ran out, but they went ahead and jumped for not wanting to ask, or knew the answer would be no. I think it that the other ways of doing it would have to be dang near completly useless before dzos would spend the money to do more than 1 planned jump run every load.

[Andrewwhyte 1]

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So perhaps it is better to do the drop in two runs, one run for the fast and one run for the slow.

Every dropzone operates under different economics, but I estimate on our DZ a second pass in our King Air would cost ~$2.00/jumper.

[DrewEckhardt 0]

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Would't it be more safe to let exit the fast freefallers first so the time needed for everybody to open his parachute is longer and as well the time that parachutes are landing?

No. People fall faster because they have less drag. Less drag means they take longer to loose their speed along the plane's direction of flight. With good exit, an average jump run speed, and no winds flat then freefly gains ~600 feet of separation. With an up-wind jump run this exit order results in even more separation because the flat group is in the winds a third longer so they drifter farther. As they approach opening altitude their drift will become the same as people under canopy, although they are in the stronger upper winds for substantially longer.

With a five second climbout, deployment along the line of flight, brakes unstowed on deployment, and canopies that can hit 40 MPH in level flight, freeflyers exiting second could just make up the difference.

Tracking in a different direction, brakes stowed, and slower canopies all make it impossible to undo that separation even if the freeflyers do nothing.

With smart people not flying back to the DZ until the previous group is open you can even avoid problems when some one in a previoous flat group tracks towards you.

[Bartje 0]

$2.00 extra , no problem for me if I have to pay it extra.
It is a suprise for me to notice thatthat safety has a price.
Is there a price for safety?

A FreeFly Gypsy

[Bartje 0]

600ft, what does it give in seconds? My expririance says that I win, or loose, more then 20 sec. Exit before the Slow freefallers after waiting 10 seconds give 10 sec. seperation. Exit before and the seperation is 30sec. In 30 seconds I'm already 1000ft lower with my canopy before opening from the next group. A fast canopy does loose altitude fast, 2000ft a min. (not agresive flying);

What's the explanation for the next incident. I was jumping after a group slow freefallers. I did wait 15 seconds, on on separation (4500ft) I tracked over the formation. Later on we looked at the video and nobody is doing anything extreem (no tracking, nothing special). The group before us was a RW6 and we where with 4 FreeFlyers. I start thinking that the drift from a group FreeFlyers can be bigger than generaly taken. It is the only explanation I can think of. There was a lot of wind at the ground and at altitude.

A FreeFly Gypsy

[Reginald 0]

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Fast FreeFallers (FreeFlyers) jump smaller groups than other disciplines but ofter fly faster canopies.

I’d not agree with that as a generalization. Canopy size is usually inversely related to experience (lots of jumps = small canopy) at most of the DZ’s I’ve visited there are experienced jumpers in both RW and FF with newer jumpers in both disciplines. It is not uncommon for a large RW group to have everything from sub 100 to 210 canopies, the same for FF.

Separation at deployment is more important than separation at landing time for the simple reason that deployment is a high-speed problem relative to canopy flight. It is almost impossible to avoid someone deploying beneath you; it should be RELATIVELY easier to avoid a canopy collision in the landing area.

My first priority on landing is to land safely, not to swoop the beer line. I am more than happy to land out in the field a bit if it avoids an impending canopy traffic jam. I’m also more than happy to hang in deep breaks and let everyone else land first too. Not to get off on a rant here but crowding in a landing area is a highly avoidable problem regardless of who exited where and who has what size canopy.

"We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP

[Bartje 0]

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I’d not agree with that as a generalization. Canopy size is usually inversely related to experience (lots of jumps = small canopy) at most of the DZ’s I’ve visited there are experienced jumpers in both RW and FF with newer jumpers in both disciplines.

Point taken.
The problem is not pointed to one kind of freefalling.
The problem is that there are too many canopies at the same place at the same moment if you do Swooping or not.
I did get an pm and I do think he operates an airplane or is a airplane owner. He said that skydivers are not ready to pay any dollars more for a jump?
One of not that many sollutions is 2 jumpruns. One run for fast fallers and one for Slow fallers. It is not the most ideal sollution but I did not hear yet an other one.
We have to rethink our way of operating when we want to keep it safe. It is the skydiver choise for jumping or not jumping but this year it was for the first time that I did not jump on a dz because I had some safety issues.

A FreeFly Gypsy

[DrewEckhardt 0]

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Fast FreeFallers (FreeFlyers) jump smaller groups than other disciplines but ofter fly faster canopies.

I’d not agree with that as a generalization. Canopy size is usually inversely related to experience (lots of jumps = small canopy)

I've observed that among recreational skydivers canopy size is more often an inverse function of age; presumably due to strong correlations between age, conservatism, the accepted practices when we started skydiving at similar ages, and girth.

At 31 my AFF instructor had Stiletto 107 and 120s, I have no beer gut, and I jump a 105. I know 40-60 year olds with more jumps than me who started when their instructors had steerable rounds or squares that didn't work well beyond 1.0 pounds/square foot, who'd be the same size without their bellies, and are under 150-170 square foot canopies. I also know younger guys whose instructors jumped cross-braced ellipticals, who've yet to develop beeer guts, and are under smaller canopies in spite of fewer jumps.

Arround here the recreational flat RW crowd is mostly older and vertical RW crowd mostly younger.

So as a rule the freefly groups here have faster canopies than RW.

Instructors seem to have more uniform wing loadings that vary little with age when sex is constant.

[LouDiamond 1]

I think this thread is starting to creep into exit seperation issues. Back to the landing area.

What hasn't been mentioned so far , is that you have far more control over your canopy than your body while in freefall in regards to avoiding others around you. The solution is better canopy control and people being able to recognize(unselfish and responsible) that they may not be able to get that swoop or land as close to the packing area as possible.

The problems arise when you have everyone going for the same target and no one willing to compromise. Canopy decent rates(sizes) will always vary and most smaller canopies will be flown by more experienced skydivers. Unfortunately, some people are only concerned with themselves and don't stop to think about the 22 jump guy or the less manuverable larger canopies. Like defensive driving, we need to be defensive pilots while under canopy, even while your trying to get your swoop on or land as close as possible. If the pattern is crowded regardless of what your hanging under, it's your responsibility to be able to recognize that you have to possibly land somewhere other than you initially wanted.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[itllclear 1]

I usually land way out. On Purpose.

Tim at Perris usually has the truck out to me before I get to daisy chain the lines, and I get back to the packing area before a lot of people who landed on the grass!

At Elsinore I usually have to walk, but at least I'm able to!

Somebody asked "Whey did you land out there? Nobody else did."

The second sentence answered the question.

"Long walk better than short ambulance ride"

Blue Skies!

Harry

"Harry, why did you land all the way out there? Nobody else landed out there."

"Your statement answered your question."

[kallend 1,625]

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I think this thread is starting to creep into exit seperation issues. Back to the landing area.

What hasn't been mentioned so far , is that you have far more control over your canopy than your body while in freefall in regards to avoiding others around you. The solution is better canopy control and people being able to recognize(unselfish and responsible) that they may not be able to get that swoop or land as close to the packing area as possible.

The problems arise when you have everyone going for the same target and no one willing to compromise. Canopy decent rates(sizes) will always vary and most smaller canopies will be flown by more experienced skydivers. Unfortunately, some people are only concerned with themselves and don't stop to think about the 22 jump guy or the less manuverable larger canopies. Like defensive driving, we need to be defensive pilots while under canopy, even while your trying to get your swoop on or land as close as possible. If the pattern is crowded regardless of what your hanging under, it's your responsibility to be able to recognize that you have to possibly land somewhere other than you initially wanted.

Absolutely correct. I was on a team that had a double fatality in 2001 due to a canopy collision at about 75' agl. There were only 11 parachutes in the air over a landing area well in excess of 100 acres. Why the collision? Neither made a hook, neither had a tiny canopy. Both were trying to land next to the packing area to make a quick turn around for back-to-back loads.

A lesson I'll not forget!

...

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

[billvon 2,400]

>Would't it be more safe to let exit the fast freefallers first so the
> time needed for everybody to open his parachute is longer and as
> well the time that parachutes are landing?

This will tend to lead to freefall collisions, which are worse than canopy collisions. In addition, at a DZ where the more experienced people are 4-way types and the freeflyers are the newer jumpers (which is often the case here) this will have the opposite effect - the faster canopies will be opening last and flying through the slower freeflyer canopoes

The best way to avoid canopy collisions (IMO) is to stick to a standard traffic pattern no matter what canopy you are flying. This means no greater than 90 degree turns in traffic, even if you are momentarily clear. It also means hanging in brakes if you are behind a slower canopy. Many experienced jumpers do not like doing these things because they are no fun, but they can reduce the risk of collisions tremendously.

In GA flying, pilots regularly use uncontrolled airports and enter/exit a traffic pattern without help from ATC. The reason this works is that everyone uses the same pattern, and you know that you have to follow the Beech Baron who's following the Cherokee. We can do the same if we want to, even if we don't have the same level of communication pilots do (radios.)

[pms07 3]

From your comments it appears the goal really should be to safely deconflict traffic in the landing area. That can be done a number of ways but things that come to mind;
- everyone flying a recognizable traffic pattern
- everyone using the same pattern and pattern entry or else landing at an alternate site
- not spiraling or otherwise flying your canopy like a buffoon in the pattern (pattern discipline)
- separate landing areas for different types of landing activity (swoop, students, standard pattern, etc...)
- established landing direction for light/no winds...everyone lands in the ssame direction

Flying an airplane at an uncontrolled airfield is a much different experience than flying your canopy usually. Pilots are used to the idea of preditcable patterns and most folks following established procedures. We would probably benefit from the same idea but on any given weekend you'll see people do really crazy stuff under canopy; spiral through traffic, landing the opposite direction of other canopys, complete disregard for pattern, yaddi yaddi...

pms

[Bartje 0]

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- everyone flying a recognizable traffic pattern
- everyone using the same pattern and pattern entry or else landing at an alternate site
- not spiraling or otherwise flying your canopy like a buffoon in the pattern (pattern discipline)
- separate landing areas for different types of landing activity (swoop, students, standard pattern, etc...)
- established landing direction for light/no winds...everyone lands in the ssame direction

When I started skydiving that was part of the first jump course. Left circuit,the canopy below you has priority, not playing with your canopy lower than 1000ft and always be aware for other canopies.
The problem is stil out there, the versitality in canopies is to big now for all to land on the same spot and create more than one landingarea only move the problem. Skydivers start flying across eachother at an other altitude.
I think we have to change our idea about exit the airplane in terms of canopies. One way to do it is to look with what kind of canopy the majority jumps in what group and start from there.

An other thing I did hear from the chief instructer at my HomeZone is when you make a rule, keep it as simple as possible but a simple rule does not cover all.

A FreeFly Gypsy

[LouDiamond 1]

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I think we have to change our idea about exit the airplane in terms of canopies. One way to do it is to look with what kind of canopy the majority jumps in what group and start from there.

With a statement like that I have to wonder how familiar you are with exit seperation issues. I see absolutely no way you could organize a load based on an individuals canopy size. What about a 4 way team where one person jumps a canopy bigger than the other 3?

The problem doesn't lie in the exit of the aircraft, it is with the pilot of the canopy.
I fly a 100 sq ft canopy and can safely negotiate slower traffic if the situation permits and I can hang in brakes to slow down if the pattern is congested and wait until it clears before making my landing. Canopy size is irrelevent in the bigger picture of landing area problems. I have seen just as many big canopies cause havoc in the landing area as I have small ones. Again, it goes back to flying ones canopy responsibly,following the pattern and thinking about the other guy.

What I think may benefit your DZs situation is a group discussion/education on this subject. Far too many times I see people all agreeing that there is a problem and no one doing something to fix it. Your DZO/ S&TA need to be involvoled in enforcing the rules and pulling those people aside who can't follow the rules.


You are clearly confusing the source of this problem

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[Bartje 0]

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What about a 4 way team where one person jumps a canopy bigger than the other 3?

When there is a group smaller than the 4 way with 2 fast canopies in it I think it is a good idea to let them go before.Especially when there is a big airplane like a twin otter.

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The problem doesn't lie in the exit of the aircraft

The problem does not lie only in the exit of the aircraft I think.

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Again, it goes back to flying ones canopy responsibly,following the pattern and thinking about the other guy.

The more people there are the more you have to anticipate the others and increase the chance for problems.

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What I think may benefit your DZs situation is a group discussion/education on this subject. Far too many times I see people all agreeing that there is a problem and no one doing something to fix it. Your DZO/ S&TA need to be involvoled in enforcing the rules and pulling those people aside who can't follow the rules.

On my homezone they do well I think. It is just that I see so many stupid things everywhere.

How to prevent traffic over the dropzone as I see it:

-Until now the ideal would be, when you jump a big airplane, to do 2 jumpruns. One run for the fast freefallers and one jumprun for the slow freefallers.
First run the biggest group so the smallest group jump in second run before tandems, AFF and high pullers and wing suit flyers.

-A dropzone with more than one landingzone with a left patern.

A FreeFly Gypsy