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Since a canopy (at least not the ones we are talking about) don't have motors there is only one way for it to generate speed. That is to trade altitude for airspeed. A canopy has a terminal velocity just like your body. And just like your body you can adjust "angle of attack" to increase or decrease terminal velocity. AOA is not technically correct but I'll use it here anyway. To increase speed to the maximum potential you need to increase AOA to the max I.e. belly to earth and you need to keep this attitude until you reach the terminal velocity for a specific canopy, wing loading, etc. So you can do a Joe Kittinger hop and pop and do 42 million degrees turn at x AOA and you will never go any faster. (Actually you will slow down but that is another topic). Additionally you can do the hardest turn possible but if you are not at that AOA long enough to reach terminal velocity you are also not max performing the canopy. So to get the maximum speed you have to hit the maximum AOA AND keep it there long enough to achieve terminal. Reversing a turn can slow you down but if you keep the same angle it won't. That means turning very hard and having good altitude judgement obviously. Caveat... A reversal probably does create enough turbulence to slow you down some. This should be able to be overcome by a long enoug turn. However, the transition from rear risers to toggles has this same effect. To what degree I have no idea but it does have an effect. To counter this I would love to see a better brake line designed. One other thing. If you turn hard enough to get your body above the canopy in theory you should increase your vertical speed because your lift vector is now pointing at the ground. The vertical speed obviously will translate into forward speed. Personally I think this is where a reversal works in your favor. To me it just seems easier to really turn hard in a reversal. I think it has to do with riser pressure and the fact that after 90-180 degrees worth of turn in one direction you know how your canopy is performing in a certain condition and you can really judge altitude loss. And you are over your spot already so a hard turn at this point keeps you more or less where you want to be. My .02c
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Now that that is all over (hopefully) there were a few people that actually had legitimate questions over Charlie's reversal technique. I don't want to speak for Charlie but I would like to expound on it a bit for them. The bottom line is that if you aren't doing it now there is no reason to start. It won't help you. It won't make you go faster. It also won't make you go slower or shorten your swoop. It is just a technique for set up more than anything. As far as negatively affecting your ability to accurately judge altitude that is patently false. I could make the exact same argument for someone not doing a reversal. But I won't because if your technique works for you then do that. Obviously a lot of us are type A's here but one thing I have to constantly remind people of, including myself, is that just because you can't do something doesn't mean it can't be done. If anyone has specific questions feel free to pm me, I'm not going to get into in public as I've seen what happens to people who just try to help or post a video to share. Kind of like having the nerve to question global warming.
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Out of curiosity, if a turn is performed at the same angle, how can reversing possibly waste energy?
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I have always had a rigger do mine so it looks tight and professional. Basically he sows a piece of Dacron into the base of the riser. The dacron is usually about the same length as a riser. On the top of the third finger trap a standard ring. Just as someone else said undo the toggle, pass the brake line through the ring on the third and reattach. And yes I would recommend passing the brake line through the slider. Packing is essentially the same except you pass the brake stow line (not sure what this is actually called) through the brake line and then the third. This is where you want to make sure the third is not wrapped around the actual riser. I always give a tug on the brake line above the stow point to seat it. After that it's ops normal.
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Hi, Wanted to take a minute to try and explain the 3rd riser setup and the advantages and disadvantages of such a set up. There are two main advantages to jumping thirds. The first and foremost is they help the canopy retain its rigidity. This is the reason we started crossbracing canopies to begin with so it just makes sense to get all we can. With traditional brakes the brake line is pulled inward towards the body and then down and out again. This is in effect "squeezing" the canopy. Since momma always told me not to do math in public let's use easy numbers. Say you are jumping a 100 sq.ft. canopy and normal brakes deform the canopy by 5% but thirds effectively eliminate this problem. With the traditional setup you are actually landing a 95 which means a higher ground speed. I don't know the actual numbers off hand but it is significant. Back in the days when a 120 was considered small it was less significant but with today's 60/70 sq.ft. canopies it is a huge difference. Just like with crossbracing you can jump a smaller canopy resulting in faster speeds and longer swoops and still have a usuable landing speed. The second reason doesn't actually affect the performance of the parachute but to me is equally important. The "twitchy" feeling someone described is something I would say 95% of people jumping them for the first time (including me) say. This feeling is because normal brakes, again bringing the line toward the body then down and back out act as a damper. You get more feel for what the canopy is doing and more control with thirds. For the pilots out there it is like the difference in flying a 182 vs a fighter (I've done both). It is quite a bit easier to over control the canopy with thirds. Indeed I've seen more than one person come in on the verge of losing control and swear to never jump them again. However, usually once someone gets used to it they swear by them. It is in effect, taking the training wheels off. In fact, I am so used to them now I feel I almost can't control a normal rig. I won't jump a small canopy without them. Disadvantages. Apart from what I've already touched on the only real disadvantage is packing. Keep in mind third "risers" don't actually have to be risers. I use a string set up to reduce bulk and drag. However it is quite easy to rig them wrong packing resulting in a twist. It's no big deal, just one more hassle when you've got a lot of other stuff going on. Additionally you can absolutely use both thirds and rears. In fact if you look at Charlie's video he is doing that very thing. Cheers and let me know if you have questions.