millertime24 8 #1 November 17, 2008 When figuring out ones WL do you add the weight the main canopy into the equasion or not? Ive talked to 2 different experienced jumpers (both over 5000+ jumps) about this. One said you add the wieght of the main (about 7lbs in my case) and the other said you dont. Any thoughts?Muff #5048 Quote Share this post Link to post Share on other sites
Remster 24 #2 November 17, 2008 Yes, you add the weight of the main. Where do you think the weight of it goes?Remster Quote Share this post Link to post Share on other sites
millertime24 8 #3 November 17, 2008 I was trying to understand why someone would say that you wouldn't and thought maybe since it supports the weight of the jumper (in an oppisite direction) then that might be why, but I truely dont know that much about the physical aspect of canopy flight.Muff #5048 Quote Share this post Link to post Share on other sites
ozzy13 0 #4 November 17, 2008 QuoteWhen figuring out ones WL do you add the weight the main canopy into the equasion or not? Ive talked to 2 different experienced jumpers (both over 5000+ jumps) about this. One said you add the wieght of the main (about 7lbs in my case) and the other said you dont. Any thoughts? You add all gear you have on at the time of the jump in to the equation.( Helmet. rig and everything that goes with the rig , cameras ect.) What ever is going to be hanging from that said canopy including weight of the canopy is part of the wing loadingNever give the gates up and always trust your rears! Quote Share this post Link to post Share on other sites
millertime24 8 #5 November 17, 2008 QuoteQuoteWhen figuring out ones WL do you add the weight the main canopy into the equasion or not? Ive talked to 2 different experienced jumpers (both over 5000+ jumps) about this. One said you add the wieght of the main (about 7lbs in my case) and the other said you dont. Any thoughts? You add all gear you have on at the time of the jump in to the equation.( Helmet. rig and everything that goes with the rig , cameras ect.) What ever is going to be hanging from that said canopy in the air is part of the wing loading Right. But is that wing itself part of its own loading?...Now my heads staring to hurt.Muff #5048 Quote Share this post Link to post Share on other sites
ozzy13 0 #6 November 17, 2008 Quote Quote Quote When figuring out ones WL do you add the weight the main canopy into the equasion or not? Ive talked to 2 different experienced jumpers (both over 5000+ jumps) about this. One said you add the wieght of the main (about 7lbs in my case) and the other said you dont. Any thoughts? You add all gear you have on at the time of the jump in to the equation.( Helmet. rig and everything that goes with the rig , cameras ect.) What ever is going to be hanging from that said canopy including weight of the canopy is part of the wing loading Right. But is that wing itself part of its own loading?...Now my heads staring to hurt. YES now your head can stop hurting Never give the gates up and always trust your rears! Quote Share this post Link to post Share on other sites
diablopilot 2 #7 November 17, 2008 The main masses 7 pounds no matter if it's packed, open, flying or on the ground.---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
shropshire 0 #8 November 17, 2008 As I understand it yes... it's your All up weight out of the door. (.)Y(.) Chivalry is not dead; it only sleeps for want of work to do. - Jerome K Jerome Quote Share this post Link to post Share on other sites
kingbunky 3 #9 November 17, 2008 when you're figureing out weight and balance for the plane, you count the wings in the take-off weight don't you? they're holding up everything, even themselves. same for your 'wing'. "Hang on a sec, the young'uns are throwin' beer cans at a golf cart." MB4252 TDS699 killing threads since 2001 Quote Share this post Link to post Share on other sites
linebckr83 3 #10 November 17, 2008 Yes. Airplanes are the same way. When calculating an aircraft's wingloading, the weight of the wings is also considered since they have to support themselves as well and not just the fuselage. So generally just add your gear's weight. Keeping it simple."Are you coming to the party? Oh I'm coming, but I won't be there!" Flying Hellfish #828 Dudist #52 Quote Share this post Link to post Share on other sites
millertime24 8 #11 November 17, 2008 Quote Yes. Airplanes are the same way. When calculating an aircraft's wingloading, the weight of the wings is also considered since they have to support themselves as well and not just the fuselage. So generally just add your gear's weight. Keeping it simple. Ah. Makes sense now. Thanks all.Edit: I wasnt sure if aircraft weight included the actuall wings themselves (not the fuel in them mind you). Now I know.Muff #5048 Quote Share this post Link to post Share on other sites
peek 20 #12 November 17, 2008 QuoteWhen figuring out ones WL do you add the weight the main canopy into the equasion or not? Ive talked to 2 different experienced jumpers (both over 5000+ jumps) about this. One said you add the wieght of the main (about 7lbs in my case) and the other said you dont. Any thoughts? It was always my understanding that the weight of the main was _not_ included, but I have no references, and have no idea where to find any. Maybe some manufacturer (with a knowledge of the history) could enlighten us. Quote Share this post Link to post Share on other sites
Skwrl 56 #13 November 17, 2008 Oooooh! So one way to increase my wingloading is to cutaway! Cooool... Skwrl Productions - Wingsuit Photography Northeast Bird School - Chief Logistics Guy and Video Dork Quote Share this post Link to post Share on other sites
JerryBaumchen 1,080 #14 November 17, 2008 Hi Gary, I don't know about that 'knowledge of the history' you speak of but as an engineer we were always taught to use 'worst case' situations. Therefore, the worst case ( weightwise ) would be if he had to make an emergency bailout, then the reserve would have to support everything that he was wearing. Just my thoughts . . . JerryBaumchen Quote Share this post Link to post Share on other sites
Andrewwhyte 1 #15 November 17, 2008 Steel is cheaper and stronger than aluminium so why don't they make aircraft wings out of them? Answer: because it is heavier. Quote Share this post Link to post Share on other sites
ozzy13 0 #16 November 17, 2008 QuoteQuoteWhen figuring out ones WL do you add the weight the main canopy into the equasion or not? Ive talked to 2 different experienced jumpers (both over 5000+ jumps) about this. One said you add the wieght of the main (about 7lbs in my case) and the other said you dont. Any thoughts? It was always my understanding that the weight of the main was _not_ included, but I have no references, and have no idea where to find any. Maybe some manufacturer (with a knowledge of the history) could enlighten us. After further investigation into this I am told you are right that its the weight suspended from the wing that is your wing loading. Its just easier to teach a student to put all gear on. Get on a scale and weigh yourself and divide it by the canopy size to get their wing loading. In the big picture does it really matter. We are talking about 7 pounds and that's not going to make much of a difference in most cases. So the right answer is NO you don't add it in. (At least that's what I'm told from several places)Never give the gates up and always trust your rears! Quote Share this post Link to post Share on other sites
pilotdave 0 #17 November 17, 2008 That's not correct. The weight of the main IS most definitely included. A wing has to support not only the weight suspended from it, but it's own weight too. A 747's wings weigh an awful lot because they're full of fuel. Your canopy might not weigh so much, but the principle is the same. What really throws off discussions of wingloading is that we have no idea how big our canopies are. There are a lot of different ways to calculate the square footage that should be used in a wingloading calculation. But we usually just use the size the manufacturer tells us. For airplanes, the wingloading is calculated using the projected area of the wing (like the size of the shadow cast when the sun is directly above) and it can include the part of the wing that goes through the fuselage. So dihedral will affect the wing area used to calculate wingloading. So yeah, the 7-lbs of main probably doesn't make much difference unless two people are trying to compare their exact wingloadings using the same canopies. Wingloading would technically be affected by loosening a chest strap too... if we used the same calculation that is used by aerospace engineers. Those several places that told you otherwise need to do some reading on dropzone.com. This has been discussed a million times. Dave Quote Share this post Link to post Share on other sites
hackish 8 #18 November 17, 2008 Well actually decrease your wingloading. You'd be losing the weight of your main, lines, risers, bridle, d-bag, pilot chute, reserve pc, reserve bridle, reserve freebag. You'd also be losing whatever falls out of your underwear after crapping yourself leading up to the cutaway... I was very surprised at how light a rig was on my back after landing under a reserve. -Michael Quote Share this post Link to post Share on other sites
pilotdave 0 #19 November 17, 2008 I'd say a cutaway increases your wingloading to infinity. Deploying a reserve is another story... depends how big it is. Dave Quote Share this post Link to post Share on other sites
ozzy13 0 #20 November 17, 2008 I always thought that you did add the main . I am getting a different answer from every person that I ask lol.People with Thousands of jumps and many years. I put a email into PD and Precision to see what they have to say.Never give the gates up and always trust your rears! Quote Share this post Link to post Share on other sites
millertime24 8 #21 November 17, 2008 QuoteIn the big picture does it really matter. Nope. Numbers are just that...numbers. I'm just one of those crazy people who ABSOLUTELY must know how everything works and why.Muff #5048 Quote Share this post Link to post Share on other sites
ozzy13 0 #22 November 18, 2008 QuoteQuoteIn the big picture does it really matter. Nope. Numbers are just that...numbers. I'm just one of those crazy people who ABSOLUTELY must know how everything works and why. I actually meant the difference with the main or with out the main included is not going to make that much of a difference 210/149 = 1.40 With main 203/149 = 1.36 without main My wing loading with or without main included Again in the grand scheme of things not a big difference I would still like to know for sure which is correctNever give the gates up and always trust your rears! Quote Share this post Link to post Share on other sites
bfilarsky 0 #23 November 18, 2008 I don't see how the main could be ignored.... the main is holding itself up, as well as the jumper. No reason it wouldn't matter. As others have mentioned, its the same in aviation - the weight of the wing is just as important as the weight of any other part of the airplane. For instance, fuel is stored in the wings, and I can sure as hell tell the difference in performance between full fuel and a light fuel load. Quote Share this post Link to post Share on other sites
pilotdave 0 #24 November 18, 2008 If you didn't include the weight of the canopy as part of the total weight of the "system," would you include the drag of the canopy in the total drag of the system? It simply makes no sense to ignore it. There's no difference between a skydiver being suspended under a canopy and a plane being held up by its wings. From a wingloading perspective, the length of the suspension lines doesn't matter. If someone designed a canopy that the skydiver sat on top of, would the wingloading calculation be any different? Dave Quote Share this post Link to post Share on other sites
BUBLHED 0 #25 November 18, 2008 IMHO wingloading is the amount of load that is placed on the wing. This does not include the actual weight of the wing, but does include everything suspended from the wing. We count the weight of the entire main assembly for two reasons 1) Makes calculations easier. 2) lines,risers,toggles,etc. must be accounted for as they are suspended wgt. So what exactly does the canopy weigh without everything attached to it? Who knows. I would think that it is maybie half the weight in this case 3.5 lbs. so that really wouldn't make any real differance to the average size jumper. Then again I could be wrong ATTACK LIFE ! IT'S GOING TO KILL YOU ANYWAY!!!! Quote Share this post Link to post Share on other sites