darkvapor

I'm sad to report that Bubbles Michalek has passed away while SCUBA diving in Australia. She was one of the most adventurous people I've ever met. And tough too--she survived several skydiving incidents that would have killed anybody else. Skydiving was only one of her many hobbies. She made friends everywhere she went, so I'm sure there are a number of people here who crossed her path. Her user name on here was selbbub78; with 3400 posts in this forum, she's probably no stranger to those of you who have been on this site a long time. Blue Skies, Bubbles. http://www.pressreader.com/australia/the-cairns-post/20150807/282574491794378/TextView

Here's mine.

The 18x27 is 486 sq in. The 23x31 is 713. Drag is directly related to the area. The bigger slider is almost 50 percent larger. "A few inches" has a big effect.

Well thank you... I appreciate the thoughts..

Never try to do blind CRW. That's a lesson I learned the hard way, too. If at any time you lose sight of the other person, use a front riser to fly down and below until you regain a visual on the other person.

True.. true.. but the point I was getting at was that perhaps a rigid parachute will be more resistant to the type of deformation that toggles and risers apply. Perhaps it is not a major factor, but I'm sure it will be some factor.. but perhaps not as much so as the others. Obviously a perfectly rigid wing will respond differently than one that has elastic/plastic behavior.. but I think you still answered my question. I think, ceteris paribus, that an airlocked wing should have a higher riser and toggle pressure. A rigid wing should be more resistant to deformation.. right? On the other hand, if the wing could deform without causing internal pressure changes (not taking into account the pressure changes due to AOA, etc), then the riser pressure shouldn't be affected by airlocks. But I will take your word for it ..

Just thinking.. but don't you want the canopy to have a little give to it? ..absorb bad docks and mismatched flying? I'm thinking that a more rigid wing will be more likely to come around and be less forgiving of poor flying.. Also.. what affects do airlocks have on toggle and riser pressure?

http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=462311#464431 There's a good post with showing the difference. I think done well, using tacked down vet wrap might work.. worth a shot.. Or maybe vet wrapping around the tapered area of the riser.. Basically something to hold the vet wrap in place.. because it might just slide ... it just depends how well the vet wrap will hold onto your risers.. However.. my guess is that small stiff blocks would work better and be safer.. I'd just hate to think what might happen if your vet wraps slips when you really need your rears.. but that's not a decision for me to make..

Vet wrap is pretty bulky and to get it thick enough to make a good gripping surface requires 5-10 wraps of the risers. This creates a lot of bulk.. not a problem for CReW dogs.. but I doubt it will fit within the riser covers of most swooper's rigs.. Vet wrap also needs to be tacked down or wrapped over blocks or it will just slide down the risers like the problem the poster was having before. I'd recommend just putting some blocks on the rear risers.. just two layers with maybe a little plastic strip on the inside for reinforcement would work.. or if you stitch the block properly so that it won't bend as much.

That's a real shame... There are some very good CRWDogs at Skydive Dallas and the N. Texas area.. You would have a blast, learn a lot.. and do it all safely.. Ask Joe or Lee to take you up some time..

Note: This perspective is not from swooping, but from CReW. While it is true that wake turbulence might move down and behind an airfoil in a flow, you have to remember that your canopy is also descending faster than the wake turbulence, therefore your "effective" wake turbulence is high and above. And yes, I think the angle at which you cross the wake is very important. Ofcourse, you have to remember that my statements are with respect to flying a PD Lightning, not high performance canopies (which will tend to exaggerate these effects). In CRW, you can ride the wake of a formation in front of you, it is bumpy, but if you stay in the wake, it will increase your descent rate (loss of lift due to turbulent air going over the airfoil). This is a trick many CRW video guys will use to stay down with stack formations (which descend much faster than an individual canopy for any given wing loading). Crossing the wake at an angle has some pretty drastic effects, especially if you are already in any attitude other than steady flight. Your canopy will experience loss of lift, but not all at once, certain parts of the airfoil will lose lift first, and your canopy will dive and turn even harder as you cross the wake. It is not a huge deal in CRW, since Lightnings are stable in wake turbulence, and you can use the wake to your advantage to maneuver yourself into position. You just have to anticipate it and react before you fly through the wake. Again, this is in respect to a CRW situation, and not swooping. My experience says that the wake extends straight behind a canopy, but rises at around a 15-30° angle (will most likely be shallower for a higher performance canopy, this angle is for a 7-cell lightning). It's effect probably extends about 6-8 canopy chord lengths. However, wake turbulence is fairly short lived, so a normal landing interval probably isn't going to affect much. Edited to add: I have not noticed that wakes off canopies "V" out like ripples following a duck. You can fly in close echelon formation with other canopies and not feel turbulence effects. I will say that the turbulence is directly behind the canopy only, with the turbulence effects spreading out no more than several feet past the wing tips. Ofcourse you have to be careful flying there for the same reason I said before. If your end cell hits the turbulence, you will lose lift on that side. The higher lift on your other side will cause your canopy to turn and dive into the turbulence.

This topic has been discussed to death in the forums. However.. What the TSA says: http://www.tsa.gov/public/interapp/editorial/editorial_1147.xml Other information: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=571858 http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=48961 http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=14057 http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=972275 http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=57455 http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=449924 And if you are still confused, do a search: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?do=search; This topic has been discussed thousands of times..

I guess I will use this thread to share an experience I had about a month ago at ZHills. We got an up and personal view of a business jet while in a CRW formation. This was a jump late in the afternoon, and we were doing a simple 5 stack to just enjoy the view and fly around. At around 5-6K, we had a 4 stack with a 5th man high and behind. I believe I was the first to see the plane approaching, so I point and yell 'Traffic!' as loud as I can. That was a complete understatement. When I saw it, the plane was on our same level, wings level, and less than 1000 feet away. This guy was doing 200-250 kts easily, and came within 200 feet of us (directly in front, no more than 100 feet below). No video on that jump, so we couldn't get a registration number off the tail, but all of us on that jump saw it go by and agree on the rough numbers given. Needless to say, we were all screaming 'holy shit' for the next few minutes. I hate to say it, but I think the pilot was hot-dogging us. I would like to say that no pilot in the world would risk the lives of 4-5 parachutists, his own, and his 10 million dollar jet. The jet was something near the Citation class of business jets (atleast in size and general appearance, I certainly couldn't tell you if it WAS a Citation). However, the main reason that I have to say that the pilot buzzed us purposely was because he was in a 20-30 degree bank towards us as he flew by. Of all the options he had if he was trying to avoid us, I do not think turning his plane into our direction would be the best. He had no altitude change during the fly by, and did a moderate bank around us. Now, I will say that was an amazing view of a plane I won't forget, but it certainly pisses me off that any pilot would endanger me and the rest of our formation. Chances are, he is not a skydiver, and has no idea about canopies and canopies together in formation. The good thing was, he was about 100 feet lower than us. If he had been at the wrong altitude in relation to us, he would have certainly put us through his wake turbulence. Also, if we had called a break down of our formation, there would be canopies all over the sky, and much harder for a pilot to avoid all of us. Anyways, I will also warn against anyone pulling very high (above 8k) at Skydive Southbeach. It is an amazing dropzone with a great view, but that damn VOR beacon on the end of the airport creates a nightmare for a parachutist. Doing CRW there a few months ago, we had two close calls within several minutes around 10-11k feet, right where the business jets fly. We had to get the pilot to drop us lower and lower on each subsequent jump, until we decided that it wasn't safe doing CRW there.

I'll be there doing lots of CReW. See ya there. -- Vadim