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npgraphicdesign

Getting back to DZ from a bad spot.

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it really is a good habit to pull abover 4k. most people like to suck it down to 3.

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Your opinion, not a fact. Really.



yeah its a good opinion though.



If you just decide to pull high, you lose any vertical separation you might have had from the group that exited after you.
You should make your intention to pull high know to the load.
3000 feet is a normal pull height for most skydives and is not really 'sucking it down' as you say.

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it really is a good habit to pull abover 4k. most people like to suck it down to 3.

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Your opinion, not a fact. Really.



yeah its a good opinion though.



If you just decide to pull high, you lose any vertical separation you might have had from the group that exited after you.
You should make your intention to pull high know to the load.
3000 feet is a normal pull height for most skydives and is not really 'sucking it down' as you say.



around here it is; most people do pull around 4k. not saying it's good or bad, just stating the facts.. i rather have a couple seconds of freefall less and having the time to get into "my slot" than not!
“Some may never live, but the crazy never die.”
-Hunter S. Thompson
"No. Try not. Do... or do not. There is no try."
-Yoda

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If you just decide to pull high, you lose any vertical separation you might have had from the group that exited after you



Vertical seperation only works when it works. It's much easier to control the factors surrounding horizontal seperation, and this why horizontal seperation is used as the primary method used to keep jumpers in the clear.

Pulling at 4k, or 8k or 12.9k is perfectly acceptable, provided that all interested parties are infromed before loading the aircraft.

Pulling higher than planned to make it back from a long spot is another story. It does work, as you're canopy has a much better glide than a jumper in freefall, and the more time you spend under canopy the more ground you can cover.

The problem is that when you deviate from the plan mid-jump on anything but a solo, you deviate from everyone's plan and that can lead to problems. You need to be aware of EVERYONE in your group if you're thinking about pulling high. If one person is not with the group and you don't see them, then pulling high is not an option. In that case, you need to stick with the original break-off and pull altitudes as discussed in the dirt dive.

The next thing to remember is that pulling high should in no way effect your break off and track procedures. If you should choose to pull high, you still need to turn out from the center of the skydive, and track to a clear area. Don't make the assumption that becasue you are pulling high you don't need to track as far. Your jump partners may also make the choice to pull high, and if everyone turns and takes a short track, you all end up pulling right next to each other.

So the idea is that however far above the original break off you are is how far above your original pull altitude you can pull. Let's say you planned to break at 4.5k and pull at 3k. If you feel like you need to pull high at, say, 5.5k, the highest you can pull then is 4k. You still need 1500ft to turn and track to a clear area, and this is not optional.

I was filming a gold medal winning 4-way team one day, and at break off I dumped in place as was the plan. Three seconds later I was snivelling 40ft away from one of the team members who was snivelling right in front of me. When we landed I asked what that was all about, and the gold medal winning, AFF-I said to me, 'When we turned to track I saw how far out we were, so I pulled right away to get open sooner". My natural response was to ask hew what ever happened to tracking away from the center, and she replied that she just forgot because she wanted to get back to the DZ.

In the end, the best plan is to spot accurately, and not to exit the plane unless you can make it home with your original plan. If you are doing a group jump where you are an inside diver, assign a competent jumper in your group to be the first to climb out so they can verify the spot, and make the go/no-go call. Once the call is made, the best bet is to trust your jump partner, and follow through with the original dive plan.

Beyond that, having a good handle on canopy control and knowing how to maximize your glide will help. Make sure you are able to set up an accurate landing pattern away from the DZ, knowing good stratagies for selecting an alternate LZ, be familiar with flat turns and be preparred for a PLF when landing off, and you should be fine in any circumstance.

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it really is a good habit to pull abover 4k. most people like to suck it down to 3.

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Your opinion, not a fact. Really.



yeah its a good opinion though.



What if there are folks above you?

(.)Y(.)
Chivalry is not dead; it only sleeps for want of work to do. - Jerome K Jerome

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Must be a UK thing.
We try for horizontal and vertical separation where possible.
3000 is considered the 'normal' pull height for groups and solos.
If you want to pull higher than this you go later in the exit order.
if a group or individual ends up moving along the jump run in freefall, there will be less chance of a skydiver in free fall colliding with an open canopy from the previous group.
We have a jump master responsible for arranging the load into this order.

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it really is a good habit to pull abover 4k. most people like to suck it down to 3.

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Your opinion, not a fact. Really.



yeah its a good opinion though.



What if there are folks above you?



every jump is different, sometimes that can be an issue, other times it wont be. i like to make it part of my plan and let other jumpers on the load know so we can all plan accordingly.

Also if i pull at 4, i would hope any other jumper in the area has already gone into a track and they are observing thier surroundings before they pull.

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Also if i pull at 4, i would hope any other jumper in the area has already gone into a track and they are observing thier surroundings before they pull.


How do you think that will help you? Do you think they'll track around you or also pull high?



getting back to the topic at hand...it will help me get back to the spot im trying to reach. and it certainly is not uncommon for the people i jump with to pull higher if we notice were in a bad spot.

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Please feel free to leave the a/c AFTER me then



Huh, So you trust him more to give you adequate separation and pull where he says he is going to, then you trust yourself to give him adequate separation so it doesn't make any difference where he pulls?

Just saying.

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getting back to the topic at hand...it will help me get back to the spot im trying to reach. and it certainly is not uncommon for the people i jump with to pull higher if we notice were in a bad spot.


I think the point is that "open a little higher" is open ended and could mean 500 feet or it could mean 2000 feet depending on who you're talking to. With wind drift and tracking direction in play and depending on who's exiting after you (head down?, belly?), pulling higher can lead to a dangerous situation that you should be aware of before you decide to take that course of action to save having a bit of a stroll.

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I must not be too good yet, I did jump the first of the load and at 3000 ft. strong wind in my face (enough to not see that I was moving almost from my position), quite far away from the landing area.

I might be wrong with my action, but I begin with front rises input to win speed (of course with the loosing height) but then using full flight hand up, I did that 3 to 4 times. Finally I did reach the DZ just about it.

Next time I will try changing my body position it might be better.

In some DZ we have some winds input with force and directions if there is a big change the pilot will tell us, but in this case did not happen it was a surprise for me.

Blue skies

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All it boils down to is simple aerodynamics. All wings have a maximum glide airspeed and a minimum decent airspeed. The two largest contributing factors are induced drag and parasite drag.

The later, "parasite drag" has many sources while flying a parachute. The largest and easiest to minimize is your frontal surface area.(Your body) Make that beeotch small.

The other, "induced drag" is a byproduct of lift and inherent to all lift producing surfaces. If you look at any wing flown at various airspeeds from their respective stall point to their bat out off hell front riser dive their are two standout airspeeds(when graphed) that both parasite and induced drag are minimized. These airspeeds directly equate to minimum rate of decent airspeed(usually the slower of the two airspeeds) and maximum glide airspeed(the faster).

One will give you maximum time aloft(minimum rate of decent a/s) and the other will give you maximum penetration or distance over the ground(maximum glide airspeed). This being said you can see how in skydiving there are huge varibles from jumper to jumper when it comes to body size/shape, weight, line types, deployment system, slider, and so on. That all being said, you can see how without a team of engineers figuring out every type of flight envelope imaginable for every parachute on the market and real time airspeed indicators not widely proliferated, this is a daunting and futile task.

So this is how I break it down. Depending on how strong the winds are you will most likely want to use your minimum rate of decent airspeed(brakes) when upwind and let the wind aid your return. When downwind you will want to use your max glide a/s(slight rears) because this will minimize induced drag that using brakes will cause allowing you to fly flatter a little faster. Since parasite drag increases dramatically with airspeed you need to keep in mind that putting down the "doughnut" :Pmay become extremely handy in this situation.

All this being said it will vary from canopy to canopy. But I do believe Ian is dead nuts on. Or I may be completely full of shit.:P

Never forget winds change aloft. Not just when planning a jump run, but remember this when even a few thousand feet above the ground. The winds can easily be 90 degrees off surface winds and even 180 degrees out.
On a side note: You guys need to stop bitching at each other and getting off topic. I have learned alot from these forums, but I have also learned that sometimes it turns into a druken pissing contest around here. Needs to stop.

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If downwind in strong conditions using rears or brakes can also get you blown back or gve you a 0:1 glide. Fronts, although they may give relatively small increase in forward speed at the expense of greatly increased sink, may not get you back from a bad spot but they can get you away from a bad landing.
Sometimes you eat the bear..............

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I have a lot of foot launching experience, both with PG wings and skydiving canopies. Having the ground there makes a great reference. I consistently get better glide on rear risers. With PG wings you can you trim tabs to "pull" on your rears while also giving a tiny bit of brake for a very flat glide. On skydiving canopies, just rears tends to give the best glide, as it does something similar (since you're pulling down two riser groups).

The only exception is a very strong tailwind, then it's better to get into brakes. Remember that your canopy travels forward pretty quickly. The tailwind needs to more than make up for the loss in forward speed you get from riding in brakes. Also, the difference between riding in rears and brakes here is negligible, so I almost always choose rears.

I've never experienced front risers or zero input providing better glide than these two techniques.

One thing to note is that you shouldn't pull your rear risers down so much that the canopy changes shape (has a "broken back"). Just enough to flatten out its angle of incidence (make it fly more parallel to the ground than at it).

My 2¢.

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As far as I'm aware only competition paragliders not recreational gliders use riser trimmers, also paramotors. Speedwings sometimes, but not always, have trimmers.

Regarding skydiving front riser use, absolutely front risers can improve glide in higher winds. I proved this several years ago on a windy but laminar day that we used for a cross-country flight. After deploying at about 13k and having a nice long ride back to the DZ we discovered that the ground winds were smooth at about canopy speed. I could easily, with no riser or toggle input, "hover" my canopy over the same spot on the ground while sinking straight down. Using rears or brakes caused me to back up while fronts let me move forward. I pretty much wore out the guy (actually my rigger and S&TA) who was chasing me to keep me from getting dragged back on landing like one of my buddies had done. I've had this discussion many times, I'd say that my experience is proof that using fronts, at least with my gear and wingloading, can increase glide over the ground in higher winds, I don't have cause to beliieve that the same wouldn't be true for all canopies/wingloadings. Naturally sink is also increased. Also using fronts in turbulent conditions could lead to a canopy collapse.

Paraglider speedbars are a great example of this effect, the other day in strong conditions while ridge soaring I found myself nearly parked withe the LZ about a mile distant. Parked is glide of 0:1, using bar I was able to get up to about 4:1 and easily make the LZ. Naturally a PG, in this case an LTF-2/EN-B is much more efficient on bar than any skydiving wing is on fronts but the intent is the same; decrease angle of attack to increase forward speed.
Sometimes you eat the bear..............

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Nope. Glide ratio is a measure of distance traveled horizontally over the ground compared with distance travelled vertically over the ground. If I'm parked I have a glide of 0:1, if I move forward as a result of using fronts or bar or whatever then I have achieved a positive glide ratio. Naturally any increase in forward airspeed is at a cost of vertical airspeed. Glide is a ground related ratio, nothing to do with airspeed.
Sometimes you eat the bear..............

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