Surf 0 #1 December 11, 2003 Jumping student gear you find yourself under a large canopy at light wing loading at 13,000 agl. Resigned to a long ride down you point yourself to the DZ (your spot is fine for an opening at 3500 AGL) And the DZ starts moving away from you. The uppers are backing you. Holding rear risers slows your backing, but you're still going backwards. What options do you have? Spiralling? Would front risers help here? My theory is that by changing the angle of attack you can trade some of that altitude in for forward speed. Anyone having experience with this please help me understand what s going on here. "Nothing is written"- T.E. Lawrence Quote Share this post Link to post Share on other sites
Remster 24 #2 December 11, 2003 QuoteHolding rear risers slows your backing, but you're still going backwards. Strange.... If you fly into the wind, holding your rears should make you land even shorter. Rear risers are good if you are flying downwind, not upwind and need to make up more ground. Full flight or front risers should be better for flying into the wind.Remster Quote Share this post Link to post Share on other sites
Jib 0 #3 December 11, 2003 QuoteHolding rear risers slows your backing, but you're still going backwards. Wouldn't rear risers make the problem worse? You could try front risers, but 13k is a long time to hold them. Are the winds lower any better? (Did you check winds aloft before takeoff? Probably or you wouldn't be jumping lightly loaded student gear in the first place) Keep pointing toward the DZ and PLAN. Figure our where you could land and where you would not want to be. Then, spiral down and see if you're still going backwards, re-assess where you can land making sure you always have an out downwind, try fronts and repeat until you move forward or have to land. -------------------------------------------------- the depth of his depravity sickens me. -- Jerry Falwell, People v. Larry Flynt Quote Share this post Link to post Share on other sites
Surf 0 #4 December 11, 2003 Yeah, thats what I thought. Any instructors, what kind of instruction do you give for this situation? "Nothing is written"- T.E. Lawrence Quote Share this post Link to post Share on other sites
chuckbrown 0 #5 December 11, 2003 Whenever you jump you should ALWAYS know what the winds aloft are (both speed and direction). If you're planning on dumping out of the plane you should know what the winds are at altitude and adjust your exit spot accordingly. You should also make sure the DZ manifest or the pilot knows you're opening high, so that other aircraft are looking out for you. But, if you're blind sided by the winds, like the other posters say, starting looking for an alternate landing spot immediately. Quote Share this post Link to post Share on other sites
rigging65 0 #6 December 11, 2003 NOTE* THIS IS NOT A RECOMMENDATION FOR STUDENTS, but... We've done test drops (and other black bag stuff) that required us to open high and sit around up there burning off altitude. When I wanted down, I'd simply stall the canopy out and wait. It's gets you down at least a bit faster, and it's fun!... As for the winds...if you let yourself get downwind on a large canopy from high altitude, well, at least you've got time to look for an alternate LZ! "...and once you had tasted flight, you will walk the earth with your eyes turned skyward. For there you have been, and there you long to return..." Quote Share this post Link to post Share on other sites
GravityGirl 0 #7 December 11, 2003 Not a continuous spiral, but do a few 360s in one direction. Stop. Then the other. In otherwords, don't get dizzy. Bleed off as much altitude as you can untile you get to a "normal" deployment altitude. Keep you eyes open. For air traffic. If you try to play with risers for 13,000 feet, you may not have enough arm strength to flare. ~~~~~~~~~~~~~~~~~ Peace and Blue Skies! Bonnie ==>Gravity Gear! Quote Share this post Link to post Share on other sites
billvon 2,400 #8 December 12, 2003 >What options do you have? 1. Go to full flight; don't use the brakes or rear risers. 2. Reduce drag. Pull your legs up, loosen your chest strap, kill your slider (if possible.) Note that this may not change your airspeed much, since your canopy is _very_ stable in airspeed (i.e. it wants to fly at a certain airspeed) but you will improve your glide ratio and that will improve your forward speed a little bit. Also note that forward speed is NOT the same as airspeed; in freefall your airspeed is 120mph but your forward speed is zero. 3. You might try front risers. They increase forward speed a little; it may be enough to keep you from backing up. Quote Share this post Link to post Share on other sites
DALAILAMA 0 #9 December 12, 2003 Spiraling is sometimes worse than simply holding what you've got. and doing nothing. Remember if you are on a large docile student canopy and you are backing up under a light wing loading, then most of the times if you begin to spiral, you simply increase your distance from the DZ due to your downwind portion of your spiral your ground speed is increased. Your crosswind portion is still pushing you downwind and if into the wind you are backing up, then spiraling is not much difference. If you think front risers will wear you out too much then there is the option of reaching up and grabbing both outside A lines and pulling them down. It is simular to the front risers without the pressure. If you have the chance try this you can see the considerable difference in your ground speed. Good Luck and Better spots to you!"Dropzone.com, where uneducated people measuring penises, has become an art form" Quote Share this post Link to post Share on other sites
Aviatrr 0 #10 December 12, 2003 Quote If you fly into the wind, holding your rears should make you land even shorter. Rear risers are good if you are flying downwind, not upwind and need to make up more ground. Where'd you come up with this? Rear risers(in the proper amount - which is not much) actually allow the canopy to fly slightly faster and flatter. Not much, but a little. Try this. Jump with somebody else at the same wing loading. Fly side by side, then try using different control inputs and see what happens. Try rear risers, front risers, and brakes. You might be suprised how your canopy reacts. DO NOT do this with two inexperienced skydivers! If possible, find a local CRW jumper to help you with this. Mike Quote Share this post Link to post Share on other sites
Dougjumper 0 #11 December 12, 2003 Precisely, using rear risers changes the Canopy's Pitch or angle of attack. Different Parachutes may or may not react differently. I do know when I was short and was last on a load to exit I would open high use about an inch or two of rear risers and I could outfly just about anyone on my DZ and make it back. Thats flying a Xaos 78 21 cell loaded at 158 lbs. As for using Front risers --gonna have a whopping good time and get down a little faster.. The glass is half full or half empty doesn't matter. Let go and have the Lord guide your path. He will take care of it all. Quote Share this post Link to post Share on other sites
Brian425 0 #12 December 12, 2003 I cannot give you any advice about flying you canopy. Please be careful about doing spirals on student gear. My coach always warns me not to do more than 3 spirals with the student cypress. After 3 hard spirals, you run the risk of a cypress fire (on the student model) It's just something to think about if you are ever really in this situation. The only time you should look down on someone is when you are offering them your hand. Quote Share this post Link to post Share on other sites
testpilot 0 #13 December 12, 2003 Quotecypress fire (on the student model) You should not be doing spirals under 1000 ft If you spiral down you will be blown in the direction of the wind and will only get penetration into the ground. Dave D830 http://www.skydiving.co.za Quote Share this post Link to post Share on other sites
pilotdave 0 #14 December 12, 2003 Not sure I understand. When you're last out, assuming an upwind jumprun, you're the farthest upwind of the airport. Are you talking about using rear risers when you're downwind of the airport? Dave Quote Share this post Link to post Share on other sites
nathaniel 0 #15 December 13, 2003 Quote Rear risers are good if you are flying downwind, not upwind and need to make up more ground. Really? It's been my gut feeling that it depends on the wind speed...going upwind when the winds are light being productive to an extent. In the original example being pushed back with no input is definitely over the threshold.... I never did the math tho... Perhaps someone physics-enabled could clarify? nathanielMy advice is to do what your parents did; get a job, sir. The bums will always lose. Do you hear me, Lebowski? Quote Share this post Link to post Share on other sites
kallend 1,625 #16 December 13, 2003 Quote>What options do you have? 1. Go to full flight; don't use the brakes or rear risers. 2. Reduce drag. Pull your legs up, loosen your chest strap, kill your slider (if possible.) Note that this may not change your airspeed much, since your canopy is _very_ stable in airspeed (i.e. it wants to fly at a certain airspeed) but you will improve your glide ratio and that will improve your forward speed a little bit. Also note that forward speed is NOT the same as airspeed; in freefall your airspeed is 120mph but your forward speed is zero. 3. You might try front risers. They increase forward speed a little; it may be enough to keep you from backing up. If actually backing up rather than just falling short of the landing zone, then reducing drag won't help and may hurt. See this thread for a full discussion: www.dropzone.com/cgi-bin/forum/gforum.cgi?post=788037#788037... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
lazyfrog 0 #17 December 13, 2003 QuoteNOTE* THIS IS NOT A RECOMMENDATION FOR STUDENTS, but... We've done test drops (and other black bag stuff) that required us to open high and sit around up there burning off altitude. When I wanted down, I'd simply stall the canopy out and wait. It's gets you down at least a bit faster, and it's fun!... As for the winds...if you let yourself get downwind on a large canopy from high altitude, well, at least you've got time to look for an alternate LZ! I think at some point you should learn how to stall and try and re-open... I know the mentality is different in skydiving, but in paragliding, we used to pull each line, groups of lines etc to induce collapsing, and try and open again, stalls, flatspins, negative turns etc... and that was before reserves existed for paragliders. and for the alternate LZ, why not go for a cross country and try and cover the max distance, with a light loaded canopy, you might catch thermals and establish a new distance record at your DZ WOW, I think I'm talking about a different sport here... ---------- Fumer tue, péter pue ------------- ourson #10, Mosquito Uno, CBT 579 Quote Share this post Link to post Share on other sites
billvon 2,400 #18 December 13, 2003 >If actually backing up rather than just falling short of the landing zone, > then reducing drag won't help and may hurt. Agreed. The only times it will help is if you are backing up very slightly, and the small extra speed you get can "stop" you - or the winds are light and you want to cover a little more ground. If you are backing up more quickly, front risers may help, both because they increase your speed a bit and get you down more quickly. And when you get down more quickly, you back up a shorter distance. Quote Share this post Link to post Share on other sites
Surf 0 #19 December 14, 2003 Just like to say thanks to all who participated here, it's nice to see a thread not turn into a flamefest and actually discuss these things in a civil manner. "Nothing is written"- T.E. Lawrence Quote Share this post Link to post Share on other sites
mr2mk1g 10 #20 December 15, 2003 When I did an intentional hop+pop at 13k under my old Sabre 190 the best thing I could do to stay where I wanted to be was to do radical 360's starting facing the wind and ending facing the wind. That way I used the speed built up in the turn to burn my way through the headwind a little. As soon as my forward speed had slowed again I would do another 360. This also had the advantage of getting me down lower quicker than just sitting there would have done, thus getting me into a lower wind speed environment. This is probably the best thing to do as it combines holding into the wind and getting down fast into lower wind speeds with the added benefit of increasing your canopy's forward speed for the periods when you are holding into wind allowing you to actually make a little headway during those segments of your flight. The effectivness of this method will of course decrease with a less docile canopy which takes longer to turn and builds up less speed while doing so. IMHO this would still be the best way to deal with the situation however. Quote Share this post Link to post Share on other sites
billvon 2,400 #21 December 15, 2003 >When I did an intentional hop+pop at 13k under my old Sabre 190 > the best thing I could do to stay where I wanted to be was to do > radical 360's starting facing the wind and ending facing the wind. I am amazed that you got your canopy to go over twice its normal speed for so long. (To make any headway while doing 360's you have to more than double your average speed to make up for the time spent going backwards.) Quote Share this post Link to post Share on other sites
Ron 7 #22 December 15, 2003 QuoteWhere'd you come up with this? Rear risers(in the proper amount - which is not much) actually allow the canopy to fly slightly faster and flatter. If you use the risers to flatten the glide, it will not speed up. It will slow down. If I was in a Cessna 150 and the engine goes out. Once I reach my best glide (Which BTW is what a canopy is lined at) if I pull up more I will not speed up. I will slow down. I will also not make any more distance across the ground. Same with a canopy. If you are backing up: 1. Turn into the wind, DON'T spiral. You will end up losing much more distance with every spiral. 2. Try to locate a landing area behind you and make your way to it. 3. You can try FRONT risers, but I bet most people can't hold the front risers long enough under a big canopy to make much progress. Brakes are rear risers will slow your forward speed, and that is the opposite of what you want."No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334 Quote Share this post Link to post Share on other sites
alan 1 #23 December 15, 2003 QuoteOnce I reach my best glide (Which BTW is what a canopy is lined at) All manufacturers do not trim all canopies the same and mfgr's trim some models differently. Typically, most canopies are trimmed slightly nose down from best glide. They do this for a variety of reasons, including but not limited to, attaining desired opening characteristics, higher pressurization, and stability. Some canopies are trimmed closer to best glide than others.alan Quote Share this post Link to post Share on other sites
Ron 7 #24 December 15, 2003 OK its still not going to speed up if you lessen the angle of attack of the wing."No free man shall ever be debarred the use of arms." -- Thomas Jefferson, Thomas Jefferson Papers, 334 Quote Share this post Link to post Share on other sites
pilotdave 0 #25 December 15, 2003 How will pulling rear risers lower your angle of attack? Dave Quote Share this post Link to post Share on other sites
