popsjumper 2 #26 May 11, 2007 Quote>A standard pattern, determined before the load, is sooooo simple. That works better in places where the winds do not shift violently and rapidly. If we tried to implement that at Perris, you'd see a lot of potential for 15kt downwinders. Nice pick, Bill. How about some more of it for context? "...A standard pattern, determined before the load, is sooooo simple. We here call our landing pattern at the beginning of the day and it stays that way all day unless the winds change more than 90 degrees and then the DZO or S&TA announces the change and makes sure the entire load knows it before takeoff. You fly the pattern in the main landing area. You want to do anything else? Go over to the alternate landing area. Winds change after takeoff? DZO calls up to the pilot. ..."My reality and yours are quite different. I think we're all Bozos on this bus. Falcon5232, SCS8170, SCSA353, POPS9398, DS239 Quote Share this post Link to post Share on other sites
billvon 2,396 #27 May 11, 2007 >Sure - but didn't you also say that manifest radios the pilot if there >are large changes in wind direction, so that they can warn the jumpers? Manifest is across the runway and behind the packing areas, so they don't have a great view of what's going on in the landing area. You could hire a guy to stand out there, relay the information to manifest, and have manifest call the plane - but if you're going to do that, you might as well just pay someone to hold the tetrahedron in one direction! They do that during some record attempts just to make sure. >Another (possible) solution is to have several "standard directions" >based on wind conditions? That way , if there IS a change in wind, >everyone knows what the change is and where they should be setting up? At Perris there are only two legal patterns/directions - left traffic to the south and right traffic landing to the north. Quote Share this post Link to post Share on other sites
phoenixlpr 0 #28 May 11, 2007 QuoteReally? When did that go into the BSR's? Tongue Do you have a BSR about common sense? You might have an attitude problem if you board the plane without having a plan. QuoteAnd if that "experienced and responsible jumper" that is first down decides to do a downwind swoop, then what? Sooner or later you collect all possible exception of the "rule". Quote Share this post Link to post Share on other sites
mnealtx 0 #29 May 11, 2007 I wasn't necessarily speaking of Perris with my examples, but just throwing the idea out there and wondering how viable the idea might be.Mike I love you, Shannon and Jim. POPS 9708 , SCR 14706 Quote Share this post Link to post Share on other sites
phoenixlpr 0 #30 May 11, 2007 Quote > I think 1st man down is a completely hokie rule Wonderful, I'm not the only one. I think that "first person down" sound bite is even more inadequate than the "45 degree" sound bite. You can't know how to setup for your own landing until you see someone else land. Well, you have the same information about the wind like to first/lower one does. I guess it would not be to hard to see the pattern he/she is setting up and just follow it. Quote Share this post Link to post Share on other sites
mnealtx 0 #31 May 11, 2007 QuoteQuoteReally? When did that go into the BSR's? Tongue Do you have a BSR about common sense? You might have an attitude problem if you board the plane without having a plan. You obviously think that the way YOU do things is the way EVERYONE does things (or perhaps how everyone SHOULD do things). I'm still a newb (obviously), but I don't recall ever seeing an "in plane" brief of landing directions. I *do*, however, make it a point to find out the standard landing direction for any dz I visit and the standard pattern direction (LH or RH).Mike I love you, Shannon and Jim. POPS 9708 , SCR 14706 Quote Share this post Link to post Share on other sites
billvon 2,396 #32 May 11, 2007 > You might have an attitude problem . . . Let's see if we can discuss this rationally without resorting to attacks. Quote Share this post Link to post Share on other sites
damion75 0 #34 May 11, 2007 Quote you might as well just pay someone to hold the tetrahedron in one direction! They do that during some record attempts just to make sure. I may be missing something here, but what is the problem with the 'traditional' arrow / tetrahedron on the ground to mark both wind direction and landing direction? In light winds you don't need someone to hold it in one position - a length of chain and a weight works quite well at several DZs. The DZ controller / CCI / S&TA needs to stay heads up to move it if it is chained down and the direction changes, but that is not such a big job. For all of the reasons SKR and Erica stated, I am not a fan of first man down (apart from everything else, it encourages racing to be that first man down). So why does the direction marker not work? If it's good enough for record attempts... *************** Not one shred of evidence supports the theory that life is serious - look at the platypus. Quote Share this post Link to post Share on other sites
lili 0 #35 May 11, 2007 Quote Well, you have the same information about the wind like to first/lower one does. I guess it would not be to hard to see the pattern he/she is setting up and just follow it. With this statement, it may be that I am not as intelligent as some people, or maybe they have an ability to predict the future, but different people are happy turning at different heights, and have different wing loadings/canopies/glide ratios, and set up differently, swoopers or not, and I don't always find it easy to work out who is going to be the first down, or which direction they are going to land, unless it is me I am not super experienced, but if at 1200 jumps I am up there on half breaks (and I'm not alone), waiting to work out my set up because it depends on someone else, I can't imagine that that is a good scenario. This situation does not encourage me to spiral down as I am concerned about someone else doing the same intending to land the other way, or starting a swoop to go from being above me to below me and landing the other way. It makes me join a game of who can stay up high the longest to make setting up as easy as possible once I have seen the landing direction. Also, it is probably irritating the swoopers to have us up there so long, when it is unnecessary and clogging up airspace. I like the idea of fixing a tetrahedron in light and variables to show the landing direction, and there is always landing further out as an option for people that want to land in a different direction. Lx Quote Share this post Link to post Share on other sites
popsjumper 2 #36 May 11, 2007 Not having put a lot of thought into it, the arrow idea seems, on the face of it, not a bad idea if you are not going to use the logic of a pre-set landing pattern. WRTO Bill's (paraphrasing) "violent wind direction changes", it may cause confusion in the pattern when it changes radically while you are under canopy and it would be no different than people chasing a windsock. But it not changing, then it's simple to tell which way to set up for and everybody sees the same thing. Somehow I get a mental picture of Perris and Eloy trying to set up landing patterns through the Dust Devils with the tetrahedron spinning like a roulette wheel...now THAT would be interesting....stupid, but interesting. My reality and yours are quite different. I think we're all Bozos on this bus. Falcon5232, SCS8170, SCSA353, POPS9398, DS239 Quote Share this post Link to post Share on other sites
rehmwa 2 #37 May 11, 2007 Quote > I think 1st man down is a completely hokie rule Wonderful, I'm not the only one. Lots of people agree with us. It makes more sense than the 45 degree farce (even if not by much). At least it's a plan. Just nowhere near as good as just having a landing direction establish by the DZ on those types of days. However, I do what the local DZ says (Have a plan that everyone knows - be ready for those that don't follow it). I just prefer a set landing direction than to leave it up to whatever random idiot gets down first. Especially if he's trying to gratify his downwinder urge at the expense of less experienced jumpers. It's more predictable than "every man for himself" and much less predictable than just having an agreed upon landing direction for light and variable days. When wind's a good 10mph or more, it's not an issue. Into the wind = landing direction and everybody can tell. Edit: Maybe we should have a list of odd, but well intentioned, safety ideas: 45 degree rule Smaller canopies are better for those having landing issues Follow the first man down Vertical separation is important in exit order Only freeflyers swoop Tracking perpendicular to jump run is something we can count on Trusting everybody on the load to dump at preassigned altitudes is something we can count on An open aircraft door is a good thing in a crash any more? ... 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
billvon 2,396 #38 May 11, 2007 >In light winds you don't need someone to hold it in one position - a > length of chain and a weight works quite well at several DZs. Well, if you let the wind shift it (at least at Perris) sometimes it will be pointing at 90 degrees to both 'legal' landing directions. If you lock it down, and the wind changes suddenly, it could take five minutes to get someone out there to change the direction - and that happens a lot during the summer. That would be a lot of downwind landings. I've often thought that manifest could have an "antenna rotator" control that could pre-position the tetrahedron on light wind days, but haven't been able to figure out the mechanics of that yet. In light winds you don't need someone to hold it in one position - a length of chain and a weight works quite well at several DZs. >If it's good enough for record attempts . . . It definitely is - if we had someone out there whose job it was to do it. Quote Share this post Link to post Share on other sites
mnealtx 0 #39 May 11, 2007 The rotator control would work... but the ones that I've been familiar with (heavyweight comm antennas) required someone to climb the tower to disengage them in high winds... maybe some sort of solenoid clutch would work?Mike I love you, Shannon and Jim. POPS 9708 , SCR 14706 Quote Share this post Link to post Share on other sites
billvon 2,396 #40 May 11, 2007 > but the ones that I've been familiar with (heavyweight comm antennas) > required someone to climb the tower to disengage them in high winds... >maybe some sort of solenoid clutch would work? Or a teeter plate that would tend to hold it in one position or the other, but could still be rotated by manifest. (Wouldn't work in high winds - but then again, in high winds you _want_ it to move freely.) Quote Share this post Link to post Share on other sites
champu 1 #41 May 11, 2007 Quote Somehow I get a mental picture of Perris and Eloy trying to set up landing patterns through the Dust Devils with the tetrahedron spinning like a roulette wheel...now THAT would be interesting....stupid, but interesting. A couple years ago, before Elsinore sacked their tetrahedron, I remember being the third person down after a jump. As I was coming off my left front riser, I saw, out of the corner of my eye, the tetrahedron spin 270 one direction, snap to a halt, then spin 180 the other direction and snap to a halt again. At the time I remember thinking, "hmm... that's odd..." and a few seconds later as I was just about at the end of my flare, my canopy lifted me about 15 feet back into the air, spun into a line twist and threw me to the ground 40 feet to the left of where I would have touched down. As it turns out, you can't see dust devils when they are over grass. Quote Share this post Link to post Share on other sites
rehmwa 2 #42 May 11, 2007 Quote tetrahedron spin 270 one direction, snap to a halt, then spin 180 the other direction and snap to a halt again. ........ as I was just about at the end of my flare, my canopy lifted me about 15 feet back into the air, spun into a line twist and threw me to the ground 40 feet to the left of where I would have touched down. My worst set down is very similar - a 4-way comp in Minnesota, DZ had two windblades. Up high, both are pointing left. At about 300 feet, one of then snaps a 180 (blades are now pointing in the opposite direction). At about 100 feet, the 2nd one snaps a 180). At about 35 feet, me and a teammate get 'elevatored' straight into the turf. Ouch. Both of us saw it coming and knew we were in trouble. Couldn't really do a thing about it either other than make sure we weren't close to each other. ... 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
Eule 0 #43 May 11, 2007 QuoteI've often thought that manifest could have an "antenna rotator" control that could pre-position the tetrahedron on light wind days, but haven't been able to figure out the mechanics of that yet. I think a key question here is: how much mass and/or friction can you add to the rotating assembly of the tetrahedron before it affects the performance? If the tetrahedron is light enough and has enough spare torque, how about permanently coupling (no clutch) a permanent magnet DC motor to the tetrahedron shaft. If the motor is open circuit the shaft freewheels. Hit the motor with DC of one polarity to go clockwise and the other polarity to go counterclockwise. Short the motor leads and it acts as a brake. I think the power supply needs to stay next to the motor, like a deep-cycle RV battery next to the tetrahedron, or a power supply off of a nearby 120 V AC line. A little box next to the motor with relays in it does the switching, and a low-voltage cable (direct bury phone wire, or sprinkler system wire, or similar) runs back to manifest where the control panel is. The control panel has a toggle switch for free/controlled and two pushbuttons for CW and CCW. EulePLF does not stand for Please Land on Face. Quote Share this post Link to post Share on other sites
mnealtx 0 #44 May 12, 2007 Nice idea - add some sort of indicator so that you know in what direction it's pointing in manual control/lock, and you're set!!Mike I love you, Shannon and Jim. POPS 9708 , SCR 14706 Quote Share this post Link to post Share on other sites
itllclear 1 #45 May 12, 2007 QuoteSomehow I get a mental picture of Perris and Eloy trying to set up landing patterns through the Dust Devils with the tetrahedron spinning like a roulette wheel ... now THAT would be interesting .... stupid, but interesting. Welcome to the desert during the summer! That's exactly what happens. It's not uncommon @ Elsinore to see windsocks at the opposite ends of the runway pointing straight out .. at each other! I have a great memory of having the wind at my landing spot be 180 off what the nearest windsock was showing. Feet, knees, nose, the canopy landed in front of me. My friend was 500 feet above me, saw my landing and thought how stupid I was for landing downwind, He landed next to me in the other direction ... feet, knees, nose and the canopy landed in front of him. The winds had done a 180 between the time I landed and he did. What works for a one Cessna DZ along the coast, with steady on shore winds, may not work at a multi turbine DZ in the desert. A downwind landing is more survivable than a canopy collision. This has been debated many times on many forums, maybe the mods should lock this thread and direct folks to the others? BSBD. Harry"Harry, why did you land all the way out there? Nobody else landed out there." "Your statement answered your question." Quote Share this post Link to post Share on other sites
