The111 1 #1 February 10, 2004 I've heard often that it's because: a) The formation stretches everyone out flat and increases each person's surface area. But I've often thought that: b) Weight/area density is not the only thing that matters... as discussed in the other physics thread, "scaling" of objects does not create identical aerodynamics. Not that a 100-way is a scale replica of a solo belly guy anyway. So I guess geometry and scale have changed. Or is it: c) a and b d) something else... Ideas are welcome, but please don't try to explain something you don't understand. That happens way too much on these forums when aerodynamics or even basic physics becomes a topic...www.WingsuitPhotos.com Quote Share this post Link to post Share on other sites
mr2mk1g 10 #2 February 10, 2004 Each individual jumper disturbs the air as they move through it - this disturbed air "fills" the gaps between people to some extent, creating the effect of a virtually solid mass. This mass has a much greater surface area than the sum of each jumpers surface area. Quote Share this post Link to post Share on other sites
elfanie 0 #3 February 10, 2004 I (the total 100% NONphysics person....so please don't laugh at the very untechnical words used) think that it's the distribution of air over the entire surface... as in... look at a feather. all of the holes in a feather don't speed it up, it slows it down more by disrupting more air. air doesn't really go through the holes because the turbulance coming around the sides will be moved outward... Ok...person A is falling, and there is turbulant air coming around them. You can feel this if you're doing a closed accordian....you have to drive in towards them or their turbulance will push on you. Once you closed it...now the turbulance can't really go BETWEEN you as much as some of that air will now be going over YOU as well... in other words...you together create one LARGER burble...because the burble is the size of person A's body, the size of your body, AND the gap between you... not technical...and I'm sure others will give a better explanation...but there's my attempt. -------------------------------------------- Elfanie My Skydiving Page Fly Safe - Soft Landings Quote Share this post Link to post Share on other sites
nightjumps 1 #4 February 10, 2004 So, if we got a large enough big way, we might be able to land it without ever having to pitch out!!! Quote Share this post Link to post Share on other sites
elfanie 0 #5 February 10, 2004 QuoteSo, if we got a large enough big way, we might be able to land it without ever having to pitch out!!! Depends on if you're on the top of the bottom of the pile... -------------------------------------------- Elfanie My Skydiving Page Fly Safe - Soft Landings Quote Share this post Link to post Share on other sites
mr2mk1g 10 #6 February 10, 2004 I actually remember reading some theoretica reseach on that exact question purportedly by NASA. I cannot say that it was genuine but I remeber reading that if we got a bigway of X then the vertical decent speed would be low enough to land. I'll try finding it - bonus points if anyone else can too. Quote Share this post Link to post Share on other sites
The111 1 #7 February 10, 2004 I think you guys are both thinking along the same lines as I was when I wrote (b), with regards to the geometry change. A solid body with "holes" in it probably doesn't fall the same as one without holes, even if they have the same weight and surface area, simply because the air moving through the gaps gets so disturbed that it contributes to the burble and the drag on the object. So maybe if there was a super huge giant that weighed exactly as much as 100 men, and had exactly the same surface area in freefall as the 100-way, he would still fall faster because of his geometry. Sad thing is I have about 10 aerodynamics books from college sitting in my closet, and I could probably settle this better if I ever had time to take them out.www.WingsuitPhotos.com Quote Share this post Link to post Share on other sites
The111 1 #8 February 10, 2004 QuoteI actually remember reading some theoretica reseach on that exact question purportedly by NASA. I cannot say that it was genuine but I remeber reading that if we got a bigway of X then the vertical decent speed would be low enough to land. I'll try finding it - bonus points if anyone else can too. I heard that too... I'd be inclined to say that has more to do with size/scale than geometry...www.WingsuitPhotos.com Quote Share this post Link to post Share on other sites
Remster 30 #9 February 10, 2004 QuoteSo, if we got a large enough big way, we might be able to land it without ever having to pitch out!!! Has anyone though of this before? Remster Quote Share this post Link to post Share on other sites
pullhigh 0 #10 February 10, 2004 I'd sure hate to be the guy that went low on that attempt... Quote Share this post Link to post Share on other sites
happythoughts 0 #11 February 10, 2004 Because the air escapes easily around one person. However, when the air from 2 people tries to squeeze between them, it slows down and is more turbulent. Skydivers lay on a column of air pressing up. Water goes around one rock easily. Same amount of water builds up pressure when going between 2 rocks because it can't get through as fast. Quote Share this post Link to post Share on other sites
skydiverek 63 #12 February 10, 2004 QuoteSo, if we got a large enough big way, we might be able to land it without ever having to pitch out!!! NASA scientists calculated, that if 200 people linked in freefall, they could land without opening their parachutes. All without using wingsuits; just normal RW jumpsuit. The trick here is that there must not be any gaps (or 'holes') in the formation - just body next to body creating a continues surface. Imagine whatching a successful attempt - 200 people descending slowly as a human canopy and landing unharmed! Quote Share this post Link to post Share on other sites
billvon 3,107 #13 February 10, 2004 >Imagine whatching a successful attempt - 200 people descending >slowly as a human canopy and landing unharmed! The last guy might have a problem getting in. Quote Share this post Link to post Share on other sites
rehmwa 2 #14 February 10, 2004 not direct reply to BV here 200,,,,,,, you might want to do another search, it was in the thousands or tens of thousands ... Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants Quote Share this post Link to post Share on other sites
mjosparky 4 #15 February 10, 2004 At the 1978 nationals at Richmond, some guy that went to a local college was going around saying they had computed, what ever that means, that if we could build a 99 way box that you could land it. At that time we were still struggling with a 50 way. I listened to him for awhile and decided if I was on it I am afraid they would land a 98 way. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
diablopilot 2 #16 February 10, 2004 QuoteI cannot say that it was genuine but I remeber reading that if we got a bigway of X then the vertical decent speed would be low enough to land. Boy, it would suck when someon droped a grip!---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
The111 1 #17 February 10, 2004 Quote>Imagine whatching a successful attempt - 200 people descending >slowly as a human canopy and landing unharmed! The last guy might have a problem getting in. If the premise is that they have to close all air gaps between each other (not sure if that's possible), I'd imagine they'd get together first, then close the air gaps. Again, I have no idea how they would go about "closing air gaps", but that at least addresses how the last guy would get in.www.WingsuitPhotos.com Quote Share this post Link to post Share on other sites
nightjumps 1 #18 February 10, 2004 Whatever NASA comes up with in numbers, it still wouldn't work. Let's say it's 10,000 for the sake of argument. You launch a perfect 10,000 way chunk. You'd still have the same effect as launching a pice of flat paper. Eventually its going to start oscillating from side to side. THe greater the distance to the ground the more side-to-side its going to get as it spills air. Sooner or later, someone's not going to be able to hold on or even if it remained a perfect formation, it may crash on a an angle equivalent to the side of the piece of paper... I'll pass on this one. Quote Share this post Link to post Share on other sites
The111 1 #19 February 10, 2004 Paper has no muscles or brain. Skydivers do. I'm still not saying it would definitely be possible to control the formation, I'm just saying that your logic is kinda similar to a whuffo who imagines that solo jumpers tumble out of control on every skydive.www.WingsuitPhotos.com Quote Share this post Link to post Share on other sites
billvon 3,107 #20 February 10, 2004 >Eventually its going to start oscillating from side to side. Happens with regular big-ways as well. It takes a while to learn to deal with waves and pulses, but it's doable. It would stand to reason that you can learn to do the same with more drag. Quote Share this post Link to post Share on other sites
nightjumps 1 #21 February 10, 2004 I should probably leave this one alone. Quote Share this post Link to post Share on other sites
bmcd308 0 #22 February 10, 2004 I bet Ron would talk really bad about the jerk that pulled from the center when he chickened out at 2 grand, causing everyone else to go in. Or maybe he would talk bad about everyone else for being such giant morons that they went in trying to land a formation. Brent EDIT: I spell like AggieDave. ---------------------------------- www.jumpelvis.com Quote Share this post Link to post Share on other sites
yoink 321 #23 February 10, 2004 That'd be fantastic! The only RW formation ever where the cameramen have to hop n pop in order to film the bugger.. Quote Share this post Link to post Share on other sites
Remster 30 #24 February 10, 2004 QuotePaper has no muscles or brain. Skydivers do. Well, kinda... lmaoRemster Quote Share this post Link to post Share on other sites
JohnRich 4 #25 February 10, 2004 QuoteBecause the air escapes easily around one person. However, when the air from 2 people tries to squeeze between them, it slows down and is more turbulent. You can feel this phenomenon yourself by sticking your hand out the door of the plane while in flight. If you put your palm into the wind, fingers together, you get a little drag. Then open your fingers up a little bit, and you'll feel even more pressure on your hand. In both cases it is the same surface area, but with fingers open a bit, you create more air turbulence and drag. I played with this for a while practicing Style, to see what hand configuration would give the maximum resistance for whipping out fast turns. A closed, cupped hand is not the best, as one might imagine! Quote Share this post Link to post Share on other sites
