popsjumper 2 #101 August 16, 2005 Quote You don't want to depend upon your altimeter - you want to recognize altitude from looking at the ground with your eyeballs too. However, the way to learn that is to use an altimeter for reference, and note how the ground looks at different altitudes. You can't learn that without the altimeter for reference. That's how you prepare yourself for an altimeter failure some day, so that you trust your eyeballs. Evidently you missed the part where I said: "Use the alti to help you learn what different altitudes look like." Thanks for the affirmation of the value of this statement. QuoteFlat desert land with nothing but low scrub brush can make your altitude appear drastically different from rolling hills with 100' tall forest trees. The reference points you use on the ground for determining "size", and therefore altitude, vary. You missed the part where I said: "and it looks very much the same." Two things: - John, I'm sorry to hear your depth perception is off...keep an eye on your altimeter - flatlands or trees. If your perception is off by that much where you would bounce over one and not the other....keep a sharp eye on the altimeter. But even over new terrain, your hard deck should not be so easily confused to the point of bouncing. - We learned early on as babies how to use our eyes to determine "size"....now, as as skydivers, we may want to learn how to use our eyes to determine "altitude" and that includes, different terrains. QuoteHighly experienced people have cutaway too high over open water and died. An altimeter will prevent that. Typical lame arguement....people have died playing tiddlywinks, I imagine. And I would modify your statement to say, "Looking at an altimeter could assist in preventing that." Sounds as though you are saying one must depend on the alti to save your butt over water....depend on it John and it will fail just when you need it. (Some law of physics or social justice, I believe. *G*) Anyway, I don't know of any altimeters that are accurate enough and/or readable enough to depend on that low to the ground/water. And if I'm that low, I'm looking at the horizon or the water, not my alti. However, aside from that....hmmm...cutting away too high? As in procedures to escape your main in water landings? If so, maybe my water training was deficient...we were told to cut (if necessary) when our feet hit the water or just before. The whole point of all of this is to use the alti to help yourself learn the visuals.....NOT to say don't use one ....and to say jumping without an alti is not a life/death event. Some great points brought up earlier, John, were that an alti is really good for break-off altitude....and really good on your wrist when you're trying to clear troubles. Thanks for your opinions.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
popsjumper 2 #102 August 16, 2005 Quote I trust my Neptune, and I know that if it fails it wont "stick" at 6,000 ft.. If it fails, I'll have immediate knowledge that it's failed as soon as I look at it instead of a false reading. Good stuff, yep. Some people have strong opinions that defy reality favoring mechanical devices, but so far, nobody can say an Neptune has "stuck" at 6k....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
MarkM 0 #103 August 17, 2005 Quote Good stuff, yep. Some people have strong opinions that defy reality favoring mechanical devices, but so far, nobody can say an Neptune has "stuck" at 6k.... First time my Neptune ever died it stuck at 11.5k on the plane ride up. Second time it died it stuck at 5k on a canopy ride down at night(though since the backlight had died, it was pretty obvious it died). Oh, and that second Neptune lock up was a friend's. Mine kept freezing up that night on the ground as soon as I turned on the backlight so I had to borrow his and break it Neptunes can and do stick. The screen basically locks ups and you have to take the battery out and put it back in to fix it. In all my cases it was a low battery that caused it, but I'm sure it can happen due to other reasons. Personally I think skydivers should always have two altimeters. That way when one fails, you have a backup and between the two you can err on the side of caution. Maybe it's a visual and an audible. Maybe it's your eyes and your time sense. Whatever's really reliable for you. But I think any single source of altitude awareness will eventually let you down. Quote Share this post Link to post Share on other sites
EvilLurker 2 #104 August 17, 2005 QuoteBut I think any single source of altitude awareness will eventually let you down. Yeah, my eyes ain't so good on a night jump. Like most things, there's got to be some common sense involved. Having an altimeter is good, having a fairly decent idea of what "low" looks like is better, just in case the altimeter malfunctions. I trust my eyes more for that, but they're not as accurate as a functioning altimeter regarding breakoff and hard deck. Quote Share this post Link to post Share on other sites
popsjumper 2 #105 August 17, 2005 Thanks, Mark...I stand corrected. Was the lock-up caused by dead batteries or was it just defective units?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
Sky15 0 #106 August 17, 2005 I'm not sure if I ever have, if I have it's only been probably once for some strange reason. Of course, I just started using a dytter recently when I got my full face. Found it uncomfortable in the frap. I am surprised at how many people do seem very dependent on audibles. And couldn't believe it when a 4 way team in practice jump had all 4 Cypresses fire. There is something to be said for going back to visual basics of looking at the ground and altimeters, I think. Not to mention, if you have a malfunction, anyone is suseptible to loss of altitude awareness due to temporal distortion, thinking they have time they don't, and we read about many low cutaways from even experienced people. For this canopy situation alone, I think visual altimeters are important. I train my AFF students from day 1 that in ANY emergency/problem situation (airplane engine failure, freefall emergency, parachute emergency) first action is to check and know altitude. (Obviously, in a/c emergency they are trained to listen to the jumpmaster for instruction, but I want to instill in them from the beginning the importance of altitude awareness.) I would have a major problem with lower experienced people not wearing visual altimeters. Personally, I think maybe they should not use audibles at first either, so that they do not become dependent on them and to encourage them to read the visual altimeter during a skydive. Just my .02 Quote Share this post Link to post Share on other sites
MarkM 0 #107 August 17, 2005 Low batteries. The battery indicator on the Neptune didn't used to work very well, but they've made it better with recent software updates. Quote Share this post Link to post Share on other sites
goose491 0 #108 August 17, 2005 I have made a few jumps without one. Hop N' Pops mainly, once on a big tracking dive. I didn't think much of it.... other than: "It would be nice to have one." Personally, I think it's stupid to jump regularily without some form of altitude determining device. Your eyes are NOT your first altimeter... they are your first altitude guesstimaters. lol. Great if you can get your break off altitude and pull time from nothing more than visual confirmation with the giant rock. But I like to have my Alti on me for three reasons already mentioned but worthy of repetition: 1) Pulling around pull time is great but pulling at pull time is better 2) During an emergency exit, it's nice to know how high you are 3) Always good to know exactly where you are relative your hard deck when fighting a malfunctioning main. N My Karma ran over my Dogma!!! Quote Share this post Link to post Share on other sites
EvilLurker 2 #109 August 17, 2005 Quote1) Pulling around pull time is great but pulling at pull time is better 2) During an emergency exit, it's nice to know how high you are 3) Always good to know exactly where you are relative your hard deck when fighting a malfunctioning main. I'm thinking not many people would argue with any of those. This IS dropzone.com, though, so stand by. Quote Share this post Link to post Share on other sites
Fast 0 #110 August 17, 2005 QuoteQuote I trust my Neptune, and I know that if it fails it wont "stick" at 6,000 ft.. If it fails, I'll have immediate knowledge that it's failed as soon as I look at it instead of a false reading. Good stuff, yep. Some people have strong opinions that defy reality favoring mechanical devices, but so far, nobody can say an Neptune has "stuck" at 6k.... I had one lock up at 4k. Was working fine on the ground, when I went up it was ok, after I got out I looked at it under canopy and it was locked at 4k. Turns out the batteries were bad, but it gave no indication of that going up. Like mentioned the battery indicator sucks. Anyways, I think the best thing is having some awareness of how the ground looks to know that its time to break/pull w/o needing some device, electronic or mechanical, to tell you that.~D Where troubles melt like lemon drops Away above the chimney tops That's where you'll find me. Swooping is taking one last poke at the bear before escaping it's cave - davelepka Quote Share this post Link to post Share on other sites
nate_1979 9 #111 August 19, 2005 Quote Like mentioned the battery indicator sucks. Or, the battery indicator sucked but has been fixed now with software updates. FGF #??? I miss the sky... There are 10 types of people in the world... those who understand binary and those who don't. Quote Share this post Link to post Share on other sites
burbleflyer 0 #112 August 20, 2005 QuoteI thinkit is fun to mess with tandem or AFF students. I keep asking them over and over "What altitude are we at?" The look on their faces when I tell them I don't have one is always funny. You are my hero. Quote Share this post Link to post Share on other sites
rwieder 0 #113 August 20, 2005 QuoteWould you, have you? Yes & Yes-Richard- "You're Holding The Rope And I'm Taking The Fall" Quote Share this post Link to post Share on other sites
EvilLurker 2 #114 August 20, 2005 QuoteOr, the battery indicator sucked but has been fixed now with software updates. Somehow, having an altimeter that has shown the need for "software updates" to work correctly doesn't leave me with a warm, fuzzy feeling. It seems like they're wide open for a lawsuit if somebody craters while using an older version. Quote Share this post Link to post Share on other sites
RogerRamjet 0 #115 August 20, 2005 QuoteHighly experienced people have cutaway too high over open water and died. An altimeter will prevent that. Quote Typical lame arguement.... I'm sure John meant that water is pretty much featureless and looks the same from 10,000 to 200. I didn't use an altimeter after about 300 dives due to a stuck one nearly taking 4 of us out. I learned to eyeball 3500 += 200 ft and 2000 += 100 ft and stopped wearing one. I proved I could do this to more than one skeptic. However, if I were to make jumps over water or desert, I would wear and use one; you simply cannot judge altitude by sight over featureless terrain. ----------------------- Roger "Ramjet" Clark FB# 271, SCR 3245, SCS 1519 Quote Share this post Link to post Share on other sites
happythoughts 0 #116 August 20, 2005 Ok... after reading the thread... I've made a few jumps without an altimeter. I have a couple of good visual cues. I could jump without it. I jump with a wrist mount and an audible. After reading the thread, the thing that I've been trying to figure out is, what is the point of jumping without one? What is the value ? Quote Share this post Link to post Share on other sites
kelpdiver 2 #117 August 20, 2005 QuoteSomehow, having an altimeter that has shown the need for "software updates" to work correctly doesn't leave me with a warm, fuzzy feeling. It seems like they're wide open for a lawsuit if somebody craters while using an older version. The good and bad thing about lithium batteries is that they deliver nearly full voltage until just before they're dead. Not easy to meter. Lawsuits - they'll argue that the skydiver should be looking where they're going. Quote Share this post Link to post Share on other sites
EvilLurker 2 #118 August 20, 2005 QuoteThe good and bad thing about lithium batteries is that they deliver nearly full voltage until just before they're dead. Not easy to meter. But my Sony camcorder uses one and it gives me a pretty accurate "time remaining" count? Plus, the unit either has an accurate way within the hardware to determine remaing power or it doesn't. If it doesn't, no kind of software upgrade is going to fix it. QuoteLawsuits - they'll argue that the skydiver should be looking where they're going. I hope there's not one that tests that theory. Quote Share this post Link to post Share on other sites
nate_1979 9 #119 August 20, 2005 QuoteQuoteThe good and bad thing about lithium batteries is that they deliver nearly full voltage until just before they're dead. Not easy to meter. But my Sony camcorder uses one and it gives me a pretty accurate "time remaining" count? Plus, the unit either has an accurate way within the hardware to determine remaing power or it doesn't. If it doesn't, no kind of software upgrade is going to fix it. Well, considering that it is fixed, I guess there is a way that software can be updated to fix it.. All the hardware has to do is be able to measure the battery voltage, ... A software update would only have to find a way to change how it takes those voltage readings to find a new more accurate way to test the battery... In the case of Neptune I'm guessing that a good way to put the battery under load for the test was the use of the backlight (which it does now). Like someone else posted, I'd rather they put the unit out and let us use it, but make it upgradable (because I love it) rather than put units through a bunch of alpha testing and release the thing in 2012. JMO... FGF #??? I miss the sky... There are 10 types of people in the world... those who understand binary and those who don't. Quote Share this post Link to post Share on other sites
EvilLurker 2 #120 August 20, 2005 QuoteI'd rather they put the unit out and let us use it, but make it upgradable (because I love it) rather than put units through a bunch of alpha testing and release the thing in 2012. JMO... I don't have a problem with anyone using it, as long as they're aware of the fact it may (currently) have reliability problems. I wouldn't be in favor of using it where students are involved. Quotea good way to put the battery under load for the test was the use of the backlight (which it does now) That makes sense, with a known load on the battery you can determine the state of charge pretty accurately. I stand corrected, that CAN be considered a software upgrade. Quote Share this post Link to post Share on other sites
MarkM 0 #121 August 20, 2005 Quote I don't have a problem with anyone using it, as long as they're aware of the fact it may (currently) have reliability problems. I wouldn't be in favor of using it where students are involved. Actually the only two problems I've really seen with the Neptune have been the battery indicator issue(which they've since fixed) and minor cracking issues with the case. Considering all the calculations it has to do to work properly(it auto zeroes itself during the day, but has to know when you're in a plane, has to detect when you're in freefall, has to detect when you're under canopy), it's had suprisingly few issues. I can't wait to see what they do with the Titan. Then we can have threads like "Skydiving without live feed heads up display GPS and freefall speed indicators". Quote Share this post Link to post Share on other sites
EvilLurker 2 #122 August 20, 2005 QuoteThen we can have threads like "Skydiving without live feed heads up display GPS and freefall speed indicators". LOL, I can't wait. Quoteand minor cracking issues with the case. Hell, I had that happen to my old Altimaster after a year. They were under new ownership and wouldn't honor the previous companies warranty, so I trashed it. Quote Share this post Link to post Share on other sites
Eule 0 #123 August 20, 2005 QuoteQuoteThe good and bad thing about lithium batteries is that they deliver nearly full voltage until just before they're dead. Not easy to meter. But my Sony camcorder uses one and it gives me a pretty accurate "time remaining" count? The Neptune uses a lithium manganese dioxide primary cell, while your camcorder uses a lithium ion rechargeable battery. Just the battery for the camcorder is as big or bigger than a whole Neptune. In the camcorder battery, there is room for a chip dedicated to keeping tabs on the battery - that's what InfoLithium means, and that's why there are "extra" contacts on the battery, for the battery to talk to the CPU in the camcorder. The chip in the battery could do anything from a simple voltage check to a complete measurement of the energy put into and taken out of the battery (like the watthour meters the electric company uses) and I'm pretty sure it's closer to the latter. You can get battery management chips that understand primary cells, but you'd have to build it into the Neptune, and space may be at a premium. The Neptune takes a CR2450 battery which is 24 mm diameter by 5 mm thick; an option would have been to have it take two CR2425 batteries which are half as thick and use one as "primary" and the other as "reserve". Run on primary until the battery test fails, then turn on an indicator on the screen and run from the reserve. You'd have to put a battery in it twice as often, but the reliability might be better. The argument between "right first time" and "mostly right first time, issue updates later" is ongoing in the computer world. My day-time job is as a computer geek and I get to deal with both philosophies. My life would be simpler if more people chose the "right first time" one, but having sat in front of the compiler with both the salesman and my boss breathing down my neck, I understand why the "issue updates later" one is also popular. :) Eule Quote Share this post Link to post Share on other sites
JohnRich 4 #124 August 22, 2005 Quotethe thing that I've been trying to figure out is, what is the point of jumping without one? What is the value ? It's "cool". Quote Share this post Link to post Share on other sites
Shark 0 #125 August 23, 2005 QuoteQuotethe thing that I've been trying to figure out is, what is the point of jumping without one? What is the value ? It's "cool". ....even cooler at night. Quote Share this post Link to post Share on other sites
