down sizing vs down wind

[firstime 0]

no flaming, just a general ?.. swooping is the ability to fly your canopy for as long as you can at an increased speed along the ground.


you are flying your (mine) 170 sabre 1:1, then decide to do a down wind, my speed has increased and now I have to keep it flying for a much longer time waiting for it to shut down. I know my canopy characterictics prior to set up. I am not looking to downsize by any means but the down wind gave me one rude awakening therefore would this be a suggestion /alternative to downsizing.... just to give an idea what you might be up against

[JohnDeere 0]

That one of the things i did before i down sized. Did some 10 mph down winders. I think it was about the same as the next lower size in zero wind. Would like to know what some exp. people think. But i think it is a good idea.

Nothing opens like a Deere!

You ignorant fool! Checks are for workers!

[rhanold 0]

Interesting question, here is my take:
I love dirty down winders. I think you should be able to land your current canopy in light down wind conditions (~10mph) before you jump a more aggressive platform. I don't think going downwind on a canopy is a good way to judge how the next size down will fly. There will be the increase in ground speed however the glide ratio and reaction speed (twitchiness) of your current canopy will remain unchanged.

Please don't get me wrong, landing your current canopy downwind is a great step in refining your flight skills and eventually downsizing but please don't think that if you can land your current canopy down wind you are ready for the next size down.

Blue skies,
Ryan

[skyshimas 0]

Downwinders are very fun indeed! There is less lift going downwind at the end of the landing hence one has to run very very fast :) but when downsizing that is not the case. Or maybe i should have said one looses stopping power when going down wind=dirty rig

[NeverTooLow 0]

Sure downwind landings should be fun, not fear before downsizing.
But it is a bad preview on the one size smaller canopy.
I downsized from 107 to 97 Katana and also lost some weight so I load the 97 only 0.1 more than I used to load my 107. Still the canopy is way more reactive and dives longer and harder than the bigger one at almost the same loading.

[firstime 0]

Thank you,

Your response to my inquiry was what I was looking for, which was "is this a valid question". The reason I presented this question was from my own experience, hence .... people always talking about downsizing. Hey try a downwind,.. maybe it might scare the bejesus out of them and stick with their current canopy............

Food for thought

[davelepka 4]

Quote

Hey try a downwind,.. maybe it might scare the bejesus out of them and stick with their current canopy............

Is it just me, or does this sound stupid?

I would reccomend that all canopy pilots do their best to avoid anything that might 'scare the bejesus out of them' anywhere near the ground.

I can't think of a worse time to be dealing with crippling fear than on final, travelling much faster than you're used to. This method of 'testing' a jumper for downsizing may solve the issue by killing or injuring the jumper before they have a chance to jump anything else.

Learning to land downwind is a slow and gradual process. It should start with a high degree of success in no-wind conditions. This should be followed by attempts downwind in very light winds, and higher wind speeds should not be attempted until reaching a high degree of success in lighter winds.

You should never attempt a downwinder with winds anywhere more than a few knots more than you have already proven yourself capable. To do so would be needlessly reckless.

A jumper who would ignore this risk, and do the downwinder anyway is the same type of jumper who would just downsize anyway, regardless of the results of the 'test'.

I would venture to say that, in skydiving, any lesson that attemtps to physically scare the jumper with actual bodily harm is not a prudent lesson. The whole point of your suggestion was to prevent rapid downsizing and, I assume, the risks involved in doing so. But your lesson does so at the expense of adding risk elsewhere. It just doesn't add up.

[rhanold 0]

Quote

Quote

Hey try a downwind,.. maybe it might scare the bejesus out of them and stick with their current canopy............

Is it just me, or does this sound stupid?

I took this as the suggestion of doing a downwind on a current canopy scary not the actual landing itself.
example;
Jumper A "I am thinking of downsizing."
Jumper B "Have you done a down winder on your current canopy?"
Jumper A "No, that’s too fast, I couldn't handle it."
Jumper B "Then you are probably not ready for the next size down."


Which I find to be a very effective conversation to gain clarity on skill level, so no I did not think it was stupid. (the above conversation is usually accompanied by more of the same on landing in rears, braked turns, accuracy landings, ect.


~Ryan

[pchapman 264]

Quote

You should never attempt a downwinder with winds anywhere more than a few knots more than you have already proven yourself capable. To do so would be needlessly reckless.

Ditto.
This is just my impression:
Even if one can land no problem in normal wind conditions, as the headwind decreases (or tailwind builds up) there's going to be a point where the next few mph change starts to get a lot trickier that dealing with the previous few mph.

It may be particularly tricky if the jumper is at the boundary of needing to use a different touchdown technique, which they aren't yet used to -- dropping in to land with a couple steps vs. having to run it out (with no vertical speed at all) vs. sliding it out on one's feet if too fast to run it out.

Some days the DZ may have "very little wind", and then in the evening there is "absolutely no wind". While it seems like almost a trivial difference in wind speed, I personally find that that difference is quite a bit bigger than one would expect if not giving it much thought.


This next part isn't as important but shows an interesting result if one works through the physics of downwinders:

It appears that for a given change in flight speed, the overall effect on touchdown speed will be greater for a downwinder than for a downsize.

Say someone downsized to a canopy 5 mph faster. In zero wind conditions, they won't be touching down 5 mph faster. First off, with the higher energy flight, the canopy may be better able to pitch up and hold the flare. (Just like doing an accelerated landing approach.) Also, changes in speeds (full flight and stall speed) will at the first level of approximation vary in a fixed ratio, not by fixed quantities. If full speed increases by 5 mph, stall speed will be up by a similar ratio of speeds, which may only be say 3 mph down at stall speed.

So despite downsizing to a 5 mph faster canopy, in zero winds, the landing may only be say 2 mph faster.

Contrast that to staying on the original canopy and doing a 5 mph downwinder. Cool, you get that same rush of the extra 5 mph speed when coming at the ground and starting the flare, just like if you downsized. But when the flare is done, that tailwind is still there, leaving you with that full extra 5 mph over the ground.

That's another reason why a few extra mph downwind can increase the difficulty quickly.

Downwinders, whatever their fun and educational value, should therefore be approached in small increments.

[rhanold 0]

Just my opinion here but learning to land downwind should be a fairly short process.
1. Get advice on how to slide in a landing
2. Practice in no wind days or into light winds until you’re consistent
3. Try it downwind in ~ 5 MPH winds
4. Go to town, landing downwind in 5 MPH winds is the same procedure for me as 15 MPH winds.

(I am only considering rolled grass fields known to the jumper for the above)

Downwind landings are nothing to fear. To the contrary I believe the knowledge of how to handle that type of situation is necessary to long term survival in this sport. (And they're fun! )

[davelepka 4]

Quote

I took this as the suggestion of doing a downwind on a current canopy scary not the actual landing itself.

I don't know, I re-read the thread, it appears as if the idea is to actually perform the downwinder (as the OP himself did). I was a little unsure as first, and held off on posting anything until the OP returned, and comfirmed my thinking.

Either way, it's not a good idea, and here's why - the guy who openly admits, "No, a downwinder is too fast for me, I'm not ready for that", is not the guy who is trying to downsize too fast or too far.

The guy who is pushing the limits and trying to rush a downsize would more likely reply, "No I haven't done a downwinder, but I see the swoopers throwing them all the time, I'll try it on the next load! Can I use my rear risers?".

The point is this, the idea relies on the jumper responding to the logic of the concept that if a downwinder is too much for you, so is a downsize. If this jumper is already ignoring all of the other (more conventional) logic against a downsize, such as jump numbers, time in sport, proposed WL, or skill on their current canopy, then I cannot see how this will make the difference.

[rhanold 0]

I see your point and after re-reading the whole thread I think the way I read it was not the way the original poster meant it.

I think the point of "scaring" a jumper out of downsizing is the wrong way of putting it. When people come to me for advice on canopy sizes there is a list of questions and talking points I cover. If I am unfamiliar with the jumper, one of these categories is current ability under their current canopy which contains the conversation about downwinders. A lot of the people I talk to have a large gap in performance knowledge/skill of their current canopy. Sometimes they have not yet thought about doing downwinders (and in general not flying their canopy to their full potential). The whole point of talking to the jumper is to make sure their eyes are open to the decision they are making including how much more they have to learn on their current canopy. That is what I was trying to express in my last post. I can see now how I was unclear.

Blue Skies,
Ryan

[davelepka 4]

I would agree with trying to 'scare' a stubborn jumper who doesn't want to listen to conventional wisdom, but only to the extent of the verbal explanation. There's a big gap between just telling somebody about how they could end up injured from an activity, and encouraging them to actually try the activity with the intention that they might scare themselves bad enough to get the point.

The real downside of this, like I mentioned before, is that the jumper who you need to resort to 'scare' tactics to try and make them understand most likely will not listen to what you have to say anyway. There's so much good information and wisdom out there that a jumper who does not respond to the 'ususal suspects' has already made up their mind as to what they are ready for.

It's a real catch-22 in skydiving. The type of people who will jump out of a plane, over and over again, week in and week out, are not always the type of people who are likely to 'toe the line' and follow conventional paths to anywhere.

[skybytch 259]

Quote

I would agree with trying to 'scare' a stubborn jumper who doesn't want to listen to conventional wisdom, but only to the extent of the verbal explanation. There's a big gap between just telling somebody about how they could end up injured from an activity, and encouraging them to actually try the activity with the intention that they might scare themselves bad enough to get the point.

Not to mention the fact that those types of people aren't likely to try the downwind landing on a hop and pop. They're going to throw it down on their next jump. Doesn't matter how many other people are in the air or that doing so endangers those other people...

[billvon 2,478]

>There is less lift going downwind at the end of the landing . . .

There's actually the same amount of lift. Your canopy doesn't really care what the ground is doing, only what the air is doing. A given canopy will let you slow down to (say) 15mph airspeed before it stops flying; your actual speed over the ground, of course, will depend on the wind.

[skyshimas 0]

i thought about my sentence so i gave a different wording at the end of the post to clear any confusion that might arise. "stopping power" anyways can't wait for them downwinders!

[amir1967 0]

Quote

>There is less lift going downwind at the end of the landing . . .

There's actually the same amount of lift. Your canopy doesn't really care what the ground is doing, only what the air is doing. A given canopy will let you slow down to (say) 15mph airspeed before it stops flying; your actual speed over the ground, of course, will depend on the wind.

finally a good answer. the only thing I can add is that with down wind, turbelent/wind sheer will have will result in unpleasent fall ( let say you land against 10 mph wind and at the end turbelnt/ gust (15mph for one second) then insted of 2 steps you make one and stop(land). when douwnwind the same condition you will be drop down on the ground without chance to run it out

AM67

[d123 1]

Theoretic nazi here but if anything on downwind with a strong wind gradient there's probably more lift in the flare than on nilwind landing or upwind landing(with the same wind gradient).

With a strong wind gradient on downwind your relative wind speed is increasing (giving more lift) and on a up-wind the relative wind sped is decreased (making you drop - less lift on flare).

I know it's not really practical but it might still be true.

Lock, Dock and Two Smoking Barrelrolls!

[firstime 0]

Hey try a downwind,.. maybe it might scare the bejesus out of them and stick with their current canopy............

Is it just me, or does this sound stupid?


My intentions were to say know your canopy, upwind downwind , crosswind prior to downsize, I made a wrong assumption that you might have got my point. We all preach "don't listen to what you read here" My statement had some validity but politically incorrect. sorry I rattled your cage bro....

[skycam321 0]

I will be experimenting with this this spring. As I recall one such down wind landing where I set up the same as the rest of the jumps that day I did not have the same amount of lift. I was unable to pull compleatly out of my dive the way I had landing into the wind.

"Stear clear of the terminally stupid!"

[matt002 0]

I have perceived less lift while landing downwind, it tends to be when the wind is quite strong and gusting. On a recent down winder tho, my wing seemed to plane out to level flight not quite as strong as on a stilletto, but definitely level flight with no pilot input, I was confused as I know from experience that my canopy does not plane out to completely level flight without gentle input no matter how high I throw it. Wind gradient would seem to explain this as the wind was strong but not gusting, just didn't think the effect of it would be noticeable.

[ozzy13 0]

Here is a good article on downsizing.

http://www.dropzone.com/cgi-bin/safety/detail_page.cgi?ID=47

Some good reading

Edited the entire quoted article - refer to link ~ Ian Drennan

Never give the gates up and always trust your rears!

[phoenixlpr 0]

Wow! Next time you just quote the whole internet here.

[ianmdrennan 2]

Quote

Wow! Next time you just quote the whole internet here.

Knock it off. He was trying to help.

If you have nothing to contribute, besides negativity, do so somewhere else.

Ian

Performance Designs Factory Team

[billvon 2,478]

>With a strong wind gradient on downwind your relative wind speed is
>increasing (giving more lift) and on a up-wind the relative wind sped is
>decreased (making you drop - less lift on flare).

I agree that might be an effect, but I think it's a minor one, since we descend through the changing layers of air relatively slowly. The bigger effect, I think, is that we all perceive distance many ways, and one of the primary ones is relative speed. If something is close to you it seems to move faster.

The classic example:

You're on final for a downwinder and you normally start your flare at around 8 feet. Everything is moving much faster so you think you are lower than you are, and start the flare at 12 feet. You plane out a bit high so you relax pressure on the toggles. Now you're at 8 feet going slower than you normally do (because you flared a little already) but everything _looks_ OK because you started out going faster than you normally do.

You finish the flare and - hey! The canopy's not planing out like it normally does! This, of course, is due to the lower airspeed you now have, but since groundspeed is even faster, you don't notice the lower airspeed. Your conclusion: the canopy doesn't have as much lift when you are flying downwind.