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20_kN

Do smaller canopies travel further in wind? First rig options?

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I have around 30 jumps. I am 155 lbs and my student/ rental rig has been a Safire 2 209 which put me around a wingload of 0.82 or so. My instructor recommended I get a 170 for a first main. The S&TA recommended a 190 or so. I am pretty conservative and I am more concerned with not getting hurt than I am with aggressiveness, so I figured I'd start with a 189 which would put me at a WL of around 0.91.

Anyway, my question is about the wind. I jump at a windy DZ. I have been pushed backwards by the wind on my 209 canopy twice already. I have read that a smaller canopy can cut through the wind a bit better, but how much better? Will a 170 or 190 vs a 209 really make any difference? The other concern is the distance covered. A smaller canopy might do a bit better in the wind, but my understanding is it falls to the ground faster so it spends less time in the air. Thus, will a smaller canopy really travel further than a larger one if it's moving faster but is in the air for a shorter period of time? Seems like you're just trading speed for duration.

All-in-all I find it a bit difficult to make a choice because on one hand a smaller canopy supposedly does a bit better in the wind, it's also more difficult to land and control in a malfunction and so I feel that I would just be trading one risk for another. As such I am leaning toward just getting the larger option since it seems safer overall.

Since I ran a Safire 2 209 for my student main, I was thinking of buying a new Safire 3 189, new Optimum 193 reserve and a Mirage container to put it in (M6 by the looks of it). That would put me at a WL of 0.91.

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First off, rarely have I seen some one injured by jumping too large of a canopy. That's not an absolute statement but skip the esoteric arguments about swooping and longer vs shorter recovery arcs or other nonsense where people are arguing for the safety of a smaller canopy over a larger one.

I'm a small guy. I started jumping when canopies were a lot bigger then they are now. You don't know shit about backing up in wind. The smallest canopy we had in a student rig was a 288 Manta. I was 135 lb at the time. Here's the real truth. Backing up is not that big a deal. Your canopy can fly in a cone. From where ever you are in the sky your canopy can fly to any point in this cone radiating out from the point you are at. We're skipping turning radius and things like that. I'm talking basic flight planing. The angle of that cone, that's your glide angle. Now when the wind blows, that cone leans to one side. Imagine taking the center line of the cone and moving it from right below you and pulling it down wind. A horizontal slice through the cone will still be a circle but the center of that circle is along this wind line. So you can still fly 20 mph through the air but the wind is backing you up 10 mph so one side of your cone looks a lot steeper then the other. These speed just add/subtract from each other. You can still fly in just as large of a cone as you always could. You have just as much control as you had before but the cone that you can fly in from that point in the sky is skewed along the wind line. If there was no wind you would still be limited by this same cone. You can't out fly your glide angle. The cone is no smaller then before. It's just slanted along the wind line. Once you understand this there is no or little difference in flying in wind. Backing up simply means that the wind is faster then the airspeed of your canopy. One side of the cone now has a negative slope. The cone is just as large. You still have just as many options as before, they are just behind or down wind of you if you prefer. None of this is a problem. The spot is just longer. And the spot is really no more critical, it's just in a different place.

Wing loading. Does not, for the most part, change the slope of the cone. Same glide angle, you just fly faster. That higher descent rate means that the wind pulls the center line of your cone less. You can penetrate better in to a slightly higher wind.

This is all fine in theory. There is one real difference in flying with wind. There is one fact that becomes important and is affected by canopy size. You don't have to fly in full flight. You can slow the decent of your canopy. depends on the canopy, but it really doesn't improve your glide angle that much, in deep breaks your glide angle goes down, but you can slow the descent rate enough for that to become dominant in high winds. YOu can slow your decent rate enough that you can let the wind carry you back along the wind line from long spots. The cone is now stretched into an ellipse reaching out to the down wind. So in a since you have more options in wind then you have on a calm day. Spots are actually much more forgiving and the stronger the wind the more this is true. Larger canopies can do this way better then small hot rods. That ability also allows you to hang above the other canopies and vertically stage, delay your landing while other smaller canopies fly down and land to reduce the level of traffic you are flying in.

So backing up is not a big deal. There are other thing that you should be much more aware of and concerned about in wind. The wind speed isn't as bad as the gust.The differences between the high and the low are more important and more dangerous then the average wind speed. Say your canopy fly's at 20 mph and stalls at 10 mph. I'm just pulling those numbers out of my ass so don't put any thing on them. If the wind were 20 mph gusting to 30 mph then each gust would, when it dies take you almost to your stall point. So under canopy the wind gust pushes you backwards, you feel the canopy pull backwards and move behind you then the gust dies and so does your airspeed and the canopy seems to surge forwards in front of you. Gust are not instantaneous but they can be a big deal for slow flying, low wing loading air craft, Ultra lights, Paragliders, and Parachutes are prime examples. This is one example where a higher wing loading/ smaller canopy can be advantageous. With their higher speed the gust is less of a factor. It's a smaller percentage of their over all speed. Answer, Keep the canopy flying fast. Don't fly in half breaks. Don't slow modern canopies down. They like the pressurization.

The other thing you should be scared of in wind is turbulence. Rotors coming off a building, like a hanger, can go a LONG way down wind. They are killers. This is some thing you should be afraid of. Be scared. You don't know me but when I tell you to be scared you'd better be wearing diapers. The proper reaction is to piss your self. Seriously, this is what to be afraid of, not backing up. Look for clean air. I don't care how far you have to land off or how far you have to walk. Look for clean air and long wind lines. this will save your life.

So that's the best explanation and advice I can give you with out busting out math on you.

Lee
Lee
lee@velocitysportswear.com
www.velocitysportswear.com

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chuckakers

Consult your instructors and the USPA Safety and Training Advisor assigned to your drop zone. They have the necessary knowledge of your abilities to best advise you.

I did. I ask a lot of questions to the instructors and I get a lot of answers, some which conflict with each other at times. I like to use many sources to learn when feasible.


Anyway, here is another question. Do smaller canopies tend to have more or less glide for a given pilot weight? For example, two guys with the same exit weight jumping out at the same time and pulling at the same altitude, but one is flying a 200 and the other is flying a 150. Assuming no winds, which could travel further if they needed to?

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Good on you for trying to find as much information as you can, but the internet can be a dangerous place in that regard. Much of the information randomly found is of rather poor quality, or from rather questionable sources. For some reasonably vetted material, check this thread in the Swooping & Canopy Control forum (don't let the Swooping discourage you, Canopy Control is vital for everyone with more than zero jumps in their logbook). A book I would especially recommend is The Parachute and its Pilot, by Brian Germain.

As to your question regarding glide, that's not trivial to answer. Having the same exit weight will result in a higher wingloading for the 150 sqft canopy pilot, which will typically result in higher airspeed. However, that just means he's down faster, not necessarily further. Whether the glide is influenced is also dependent on the canopy designs and the actual wingloadings. Some canopies are of a design that doesn't really like high wingloading, and they really suffer in performance at very high wingloading.

However, my gut feeling would be that due to reduced line drag on the 150 (smaller canopy = shorter lines), the 150 will have slightly better efficiency, and could glide a little bit further. However, these are second-order effects, and should NOT influence your canopy choice in whatever way. Pick a canopy that has handling characteristics (including forward speed, determined in large by your wingloading under the canopy), that you can handle when already deep in the shit (think low-pull, poor spot, crappy winds and landing in a tight field all at once).

Also, your assumption of no winds is really limiting. There are almost always winds, and they always influence the options you have under canopy, both in terms of glide, and in terms of reachable area while flying upwind/downwind/crosswind/halfbraked/fullybraked/nobrake.

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IJskonijn

Good on you for trying to find as much information as you can, but the internet can be a dangerous place in that regard. Much of the information randomly found is of rather poor quality, or from rather questionable sources. For some reasonably vetted material, check this thread in the Swooping & Canopy Control forum (don't let the Swooping discourage you, Canopy Control is vital for everyone with more than zero jumps in their logbook). A book I would especially recommend is The Parachute and its Pilot, by Brian Germain.

As to your question regarding glide, that's not trivial to answer. Having the same exit weight will result in a higher wingloading for the 150 sqft canopy pilot, which will typically result in higher airspeed. However, that just means he's down faster, not necessarily further. Whether the glide is influenced is also dependent on the canopy designs and the actual wingloadings. Some canopies are of a design that doesn't really like high wingloading, and they really suffer in performance at very high wingloading.

However, my gut feeling would be that due to reduced line drag on the 150 (smaller canopy = shorter lines), the 150 will have slightly better efficiency, and could glide a little bit further. However, these are second-order effects, and should NOT influence your canopy choice in whatever way. Pick a canopy that has handling characteristics (including forward speed, determined in large by your wingloading under the canopy), that you can handle when already deep in the shit (think low-pull, poor spot, crappy winds and landing in a tight field all at once).

Also, your assumption of no winds is really limiting. There are almost always winds, and they always influence the options you have under canopy, both in terms of glide, and in terms of reachable area while flying upwind/downwind/crosswind/halfbraked/fullybraked/nobrake.



I guess what I was getting at was a scenario that I experienced the other day. I did a jump the other day where some guys from my load landed off field as they couldent make it back. We all jumped out on the same load and pretty close to each other in terms of timing out of the airplane, but two guys ended up landing off field as they could not make it back. They were running fairly small high-performance canopies and I was running a large dosile canopy with a light wing loading. I had no problem getting back and when I flew over the spot they landed I still had over 2500'. Now granted I am sure I pulled at a bit higher altitude than they did which helped me get back, but I couldent help wonder if the reason why they had trouble getting back was because they were on small canopies with high wing loadings, and in my case having a large canopy with a low wingloading helped me glide further, or if it was just something else entirely. That prompted the question at to whether higher wingloading increases or decreases your ability to travel further from a long spot.

And yes, there was some wind that day. Not enough to back me up flying into the wind, but it was noticeable.

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For that particular scenario, the wind is very important. You have a much lower airspeed than the small home-sick bowling balls the other guys were flying.

I'm going to make two assumptions here: 1. you were all dropped quite a bit upwind from the DZ. 2. your glide angle is exactly the same as their glide angle, and airspeed is the only difference.

Now, you all experienced exactly the same wind speed (the gods of weather hate us all equally), but with your lower airspeed (and thus lower downward speed) you stayed up in that wind much longer. If the bowling balls were down in a minute, and you took five minutes, and we assume 15kn winds up at altitude, the winds pushed you a whopping 1852 meters further downwind!

Glide angle has nothing to do with it. Wind has everything to do with it. Generally, higher airspeed means you're less affected by wind, but also less able to use it to your advantage.

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I spoke with an instructor today and was told something that seems contrary to what I've been taught by other instructors in the past. I was told if I am coming back from a long spot and I am downwind from the DZ, fighting against the wind to get back, that I can pull on my rear risers to travel further. He mentioned if I am coming back from a longspot with the wind, fly in brakes. If I am going against the wind, fly with some pull on the rear risers.

I have flown in brakes and with risers effectively a several times already, but I've never tried flying against the wind with some pull on the rear risers as it was always my understanding that action will make things worse.


So can anyone confirm? If you're flying into a headwind from a long spot, will flattening out the canopy with the rear risers help or hinder your ability to travel far?

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Apparently it can depend on the canopy. You have to figure your own out. Another approach (mine, given that I haven’t bothered to learn my canopy’s behavior under all bad situations like this) is just to
  • a. Not jump when the winds are ridiculous
  • b. Be comfortable with landing out

    If you’re comfortable with the outs, that’s a safety margin.

    Wendy P.
    There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown)
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    I think the only time you might see that is with highly loaded very steep trimmed canopies. Pulling on the rear risers, kinda sorta, trims the canopy flatter. In theory it's flattening the trim of the canopy and improving the glide with out decreasing your speed as much as riding in deep breaks. You're actually distorting the canopy quite a bit if you pull to far on the rear riser so if you're trying this be subtle, an inch or two. With a really highly loaded canopy that is penetrating into the wind you might improve your landing point by trimming the canopy slightly flatter. You might see this with the really steep ground hungry canopies. A lot of the swooping canopies are very steep and very ground hungry with high decent rates and are well bellow best glide angle. As to the second half of his comment, that is exactly right and it goes double for small aggressive canopies. If you are long and running down wind to get back to the DZ in high wind you are much better off reducing your decent rate as far as you can and letting the wind carry you back. This is doubly true for small ground hungry canopies. Their glide is shit. The only chance they have to make it back is to hang in breaks reducing their decent rate as far as possible to let the wind help them back.

    Lee
    Lee
    lee@velocitysportswear.com
    www.velocitysportswear.com

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    That would be called CRW. And yes you can do that. The front risers carry most of the load and we would fly front riser trim flying wings an extended period of time on the big diamonds. There are tricks to how you do it... it also helps to have large forearms.

    The rear risers are much easier to pull. You can pull them with no problem. But the best way is to reach up and, kind of twist your arms around them. You reach up to the inside rather then the out side and kind of twist your forearm. You can put a couple of inches of trim into the riser with very little effort. Your arm is strong that way and you have advantage. You can hold that forever.

    Lee
    Lee
    lee@velocitysportswear.com
    www.velocitysportswear.com

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    mark

    ***. . .I can pull on my rear risers to travel further. . .

    try hanging on a chin-up bar for 4 minutes.

    -MarkI have. Anyway, holding the rears only takes about 40 lbs on my canopy, not my entire body weight, and they are not that hard to pull on for a few minutes at a time. I've done it a few times already. The fronts are a different story and those require almost my entire bodyweight.

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    20_kN

    I spoke with an instructor today and was told something that seems contrary to what I've been taught by other instructors in the past. I was told if I am coming back from a long spot and I am downwind from the DZ, fighting against the wind to get back, that I can pull on my rear risers to travel further. He mentioned if I am coming back from a longspot with the wind, fly in brakes. If I am going against the wind, fly with some pull on the rear risers.

    I have flown in brakes and with risers effectively a several times already, but I've never tried flying against the wind with some pull on the rear risers as it was always my understanding that action will make things worse.


    So can anyone confirm? If you're flying into a headwind from a long spot, will flattening out the canopy with the rear risers help or hinder your ability to travel far?



    The only answer to this is:

    "It depends."

    The whole idea behind this is that you are slwoing your descent, and slowing your forward speed. The reason it extends your glide is because you are slowing your forward speed less than you are slowing your descent rate. That gives you a shallower angle and extends your glide.

    Generally, rears take less forward speed away, but don't slow the descent quite as much. Brakes will slow the descent more, but at a cost of more forward speed. (again, generally).

    If you have a tailwind, you don't mind losing more forward speed because the tailwind pushes you across the ground faster. With a headwind, losing forward speed may give you zero groundspeed (depending on the wind and on the speed of the canopy), which gives you a vertical descent.

    This is all stuff that varies from canopy to canopy, and jumper to jumper. The only way to find out for sure is to experiment.

    One thing I was taught early on is that if I'm not sure that I can make it back, don't try. Pick an out early enough that I have plenty of choices and can pick a good one. Don't wait until my choices are the trees, the power lines, the freeway or a tiny, tiny back yard.

    I landed out a couple years ago, the DZO came out to pick me up. On the way back he said that they were standing by the hangar, watching me come in. They could see that I was very marginal to make it back, and 'short' would have meant on a busy freeway. "Out" was a farm field. They were standing there saying "Don't try to make it back", knowing I couldn't hear, but that's something we all do.
    "There are NO situations which do not call for a French Maid outfit." Lucky McSwervy

    "~ya don't GET old by being weak & stupid!" - Airtwardo

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