dnewcomer

I was trial jumping a rig I considered buying for water jumps. My regular rigs all have BOC PC, but water rig had a leg strap PC bag. I thought about it 100 times on ride up and practiced reaching for leg bag to remind myself, but still reached for BOC at pull time. (Duh!) Took me a couple of seconds to remember..........."leg strap PC." I had plenty of time to get PC out. I can still remember the momentary confusion when I reached for the BOC and nothing was there. The reason these things happen is because your brain is almost working instinctively in FF.....probably even more so if you have >500 jumps. Your body is running like a plane on "autopilot" if everything is happening in the usual way. Some people spent to last few seconds of their life reaching for a deployment handle that wasn't there, then pulled silver too late. LESSON: Always plan to open a little higher when jumping a rig with different deployment system than you're accustomed to. Give yourself plenty of altitude/time to figure it out. COROLLARY: If you're jumping any rig for the first time, plan to open a little higher to give yourself extra time to deal with the unforeseen. D--

In skydiving, as in skiing double-black diamonds, rock/ice climbing, scuba diving, etc. it is always safest to err on the conservative side. If you thought the 220 landing was fast, imagine what it would have been like flying a 150? I'd go with the larger reserve for now. BTW, why did you have to pull silver? Keep safe out there! D-- www.newconthenet.com

The term "minor canopy collision" is an oxymoron (like "honest politician"). Who would consider any canopy collision with a freefaller to be "minor"??? D--

Two Comments: #1 -- We all have a volume of knowledge that might be thought of as a occupying a sphere of certain size. Individuals with lots of knowledge have enough information to occupy a very large sphere......yet they can see there is an even larger body of knowledge just outside the perimeter of that sphere that they do not know. People with little knowledge have enough information to fill only a small sphere, so they don't see much knowledge on the perimeter of that small sphere that they do not know. They think they are the masters of everything that can be known about......anything. It may seem paradoxical, but the more you learn, the more you realize how little you know. (Notice this is not the same as saying: "The more you learn, the less you know.") #2 -- Someone once said, "Wisdom does not necessarily come with age. Sometimes age comes alone." This may apply to some long-time jumpers who have been in the sport for many years. The people I listen to most carefully when they talk are those with 8,000 or more jumps who have never had a serious accident and are still jumping canopies >150 sq ft and wing-loaded

R-- I believe I am safer (but I wouldn't get into a pissing contest about it). I've jumped w/o an altimeter due to unforeseen circumstances (as most skydivers have), but I wouldn't do it or recommend it on a regular basis. I use every sensory clue I can get (as you do) to determine when it's pull time, including altimeters. I wouldn't want personal hubris or ego to get in the way of good judgement. I hear you. I understand what you are saying. You are an exceptional person if you feel you could jump routinely without using an altimeter and be as safe as when you jump with one. IMO this would be inadvisable for most skydivers. Blue ones. D--

R-- I don't want to let your comment about jumping without any altimeter at all go unanswered. (I am assuming I understand correctly what you said.) Here is another opinion for consideration...I don't mean to be telling anyone else what to do. We all have to make these decisions on our own. This is not a criticism directed at a person, but rather a criticism of a practice. I hope it is received in the spirit that it is offered. IMHO it is extremely poor judgement for anyone to routinely jump without an altimeter other than one's own visual sense. It doesn't really matter how experienced you are or how many jumps you have made. I furthermore believe it is borderline good judgement to jump with only an audible altimeter, although I am aware many very experienced skydivers do this routinely. When people do this, they should realize they are increasing their risk for an accident. Electronic devices, including audible altimeters, are notoriously unreliable. Mechanical aneroid altimeters can fail, but they are more reliable than audibles. Knowing when to pull is more than watching your altimeter or listening for a tone. When going up in the plane, notice what altitude the bottoms of nearby clouds are. If they're at 5,000' (which is common in the northeast), you're going to have to start thinking about pulling ~8 seconds after you pass below the surrounding clouds. If you're skydiving in a 4-way and everyone else is tracking (you agreed to track at 4,000') but your altimeter still reads 5,500', something is wrong. When you're jumping solo, watch for the people who exited before you.....if you're free falling past open canopies 500 yards downwind and your audible didn't go off, something is wrong. Keep your eyes and ears open, and try to be ready for every contingency (not using any altimeter at all IMHO is not being prepared). If all the gadgets you are carrying with you to tell you how high you are have failed, err on the side of opening early unless that creates a significant danger for others. Having said that, if I am doing a 4-way RW with people I know well and realize I have not got my altimeter on the ride to altitude, I will probably alert everyone else and jump anyway, depending on them to know when to track & pull. If anyone ever has a skydiving accident and it is discovered that he/she was not carrying an altimeter of any type, I think we can all imagine what conclusions will be drawn.....irrespective of the actual cause of the accident. Keep safe out there. D--

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Scott, Other than the student rig I learned on, Triathlons are all I've jumped (175 and 130). I had the same problem you had....at first. Then after trying numerous suggestions from various "experts" that failed, someone with 14,000 jumps told me I wasn't flaring fast enough (for a Tri) to get the lift I needed to keep my canopy in level flight until it's speed bled off. Tri's do not fly or flare like elliptical canopies. I tried flaring much faster and found he was right. I usually pull the toggles about 3/4 of the way in one second --- this gets me to level flight. Then I finish the flare when my canopy starts to drift downward. If you do this properly, you should not have to run out your Triathlon landings even under no wind conditions. I agree with Ari and Andy....practice flaring at altitude to get the feel of the flare and how your canopy behaves with various toggle inputs. Find the speed of flare that "levels out" your canopy's flight path. That's the rate of toggle input you'll want to apply when landing. If you pull toggles too fast, you'll get so much flare you'll go upward. Also to get the max. flare, you always want to be landing at max. glide, so don't try landings in partial brakes. The faster you're coming in, the more lift you'll get when you flare. Some people may not agree with this advice, but it worked well for me and others flying and landing Triathlons. Good luck and keep safe. Dave

Art, You are sooooooooooo right! When I got divorced in PA, she got the mine and I got the shaft. PA judges seem to hate husbands, maybe men in general. Don't know why. Dave

IMHO no helmet is going to prevent major head trauma in a high-speed collison (60-120 mph) with the ground, a fence, or another skydiver. That having been said, helmets DO afford some protection from head lacerations, ear injuries, etc. during minor bumps. I used to wear a helmet without ear coverings and had a few ear abrasions. PA DOT-approved motorcycle helmets provide much more protection but are bulky and not very practical for sport skydiving. I personally choose to wear my MC helmet when riding my Harley. To wear or not to wear is an individual decision in skydiving and MC riding (most states). If you never wear a helmet while skydiving, sooner or later you are probably going to have at least a minor head injury that could have been avoided with protective head gear. It's the nature of the sport. But consider: You never see a rider in a professional motorcycle race without a helmet.....and they don't go much faster than skydivers. Most people who choose to not wear head gear when asked about it say, "I don't want to wear a helmet. And I'll do as I damn well please." OK. Some individuals never let good judgement get in the way of their very large egos. D--

Short answer: atmospheric pressure at sea level is 1013.25 millibars or 29.92 in. of Hg (same pressure as is exerted by a column of water about 33 feet high). At 18,000 feet altitude, assuming everything being equal (temp., for instance), the pressure exerted by the atmosphere is about 1/2 of sea level, or ~500 mb.......At 14,000 feet, approx. 3/4 of sea level. Based on this information, the vertical vector (downward movement) of your canopy's flight path should be about 1.3 times as fast at 14,000 feet altitude compared to sea level. Since the air density is only about 3/4 of sea level, the canopy does not have as many molecules of air to ride on, therefore it descends faster. These numbers are rough estimates only. At high altitudes, it is much colder than at sea level, and this compensates somewhat for the lower density based on altitude alone, but the overall effect is much thinner air so you will still come down much faster. D--

In this context I did not mean to imply anyone who ever makes a skydive without a helmet is literally "crazy" (as insane) and was only using this word as a figure of speech. Sorry if it offended some people who choose to skydive from time to time without a helmet. Everyone has a right to his own opinion about wearing a helmet or not as long as his behavior doesn't compromise anyone else's safety. D--

You are right! I was a trauma surgeon for 15 years. I can tell you and any neurosurgeon will agree: little protection from high impact injuries is afforded by skydiving helmets. State approved motorcycle helmets in PA have three to four times the padding of any skydiving helmet on the market. The best you can hope for is that the helmet will prevent some head lacerations. When your head (even in a well padded helmet) traveling at a high rate of speed, >20 mph for instance, hits another object, the helmet's motion in space is stopped abruptly and your brain impacts the inside of your skull just as if it had impacted the object. Putting your head in a doorway and closing the door on it with or without a helmet is a meaningless test. A more accurate test would be to allow someone to hit you in the head with a full baseball bat swing with and without your helmet.......obviously this is inadvisable and foolish. But it illustrates the minimal protection you get from a helmet in high impact head trauma. Helmets can provide some protection in low impacts, therefore we would all be crazy not to use them every time we skydive.

IMHO it would be extremely dangerous and probably inadvisable for an inexperienced skydiver (perhaps

B-- I believe this thread represents the best reason DZ.com exists. Too bad everyone who ever exits a plane to make a skydive is not going to read it. The idea of making copies of this info for wide distribution at DZ's on Safety Day is a good one. Maybe the USPA should send a memo or email out to all DZ's, DZ owner/operators, and S&TA's emphasizing that the "45 Deg. Rule" is invalid and should never be used or recommended as a technique for determining exit separation distance. It would seem that this should be part of their goal to maximize the safety of the sport. D--

Chris, I hope you didn't hurt yourself typing that post. I've been told by experienced skydivers out there (often with many thousands of jumps) about the virtues of the "45 deg. rule." OK...they're wrong. Obviously not everyone is reading the threads on DZ.com. I guess this proves the adage, "Knowledge and wisdom don't necessarily come with experience; sometimes experience comes alone." It's amazing how many so-called experts can disagree on a major issue -- but none of them ever seems to be in doubt about his or her opinion. I believe a few upstart engineers have even recently questioned the 100 yr old theory of how an airfoil creates lift. (My God...the Holy Grail of aerodynamics!!! Isn't anything sacred?) There will probably never be a "precise" formula that can accommodate all variables to accurately determine exit separation on all jump runs. The necessary information is imprecise by its very nature. It would be easier to write the formula needed to send a landing craft to Mare Imbrium. The best anyone can do will have to be a generality that gives a reasonable margin of safety for all situations -- whatever that may be. Dave

QuoteHow about this, we get all the engineers. They put their heads together, and after the loud dull thud, come up with a formula that takes all the different variables, aircraft speed and direction, different wind layers of speed direction and altitude, different fall rates etc. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Unfortunately all this data is too imprecise to plug into a consistent, reliable formula: (1) For starters the "winds aloft" info is obtained from ascension balloons released by the NWS at various sites (not at your DZ), and even THEY say their data is inexact at a given point in time. Also winds are variable throughout the day -- they only release two balloons to measure the winds twice a day from each specified weather station. (Check out http://aviationweather.gov/products/nws/fdwinds/dynamic/boston_fd1.shtml). (2) Another point: taking into account the imperfection of ascension balloon technology, there is rarely a great deal of difference in wind speed and direction at altitudes between 3,000' and 12,000'. If you study the NWS wind charts regularly, you will come to realize this is so. (3) Various RW 4-ways can fall at significantly different rates: 110 mph or 122 mph, a difference of 17'/sec (the faster grp will be covering 600+ more feet of FF than the slower before opening). The fall rate difference can be even greater for bigger ways depending upon the spread of participants. (4) Not everyone tracks as well as the next guy. How far from the center of the formation do you calculate an "average" track from a 4-way? 8-way? etc. to plug into the formula? I suggest a formula with the "KISS" approach and err on the side of safety -- something that will apply to all situations. Here's a starting suggestion: If the ground speed of the aircraft is 60 knots or more (>101'/sec), count 10 seconds between groups of one or two jumpers; for groups of three or more, add one additional second of space for each jumper (4-way would need 14 seconds); plus for each 10 knots slower than 60 knots ground speed, add 2 seconds of time (for 50 knots, you'd space solos 12 seconds; 4-way would need 16 seconds). This formula would be used for any skydivers...flat, FF, sit, hydbrid, etc. It's conservative, but safe. Can anyone suggest any good mods. of this formula? Our jump pilots should probably be making a second pass more often than they do now. Dave

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ John, I don't think you can write a formula that would apply to every contingency because it depends on the number of jumpers exiting in each group, not the whole load. For example, an 8-way will need more room to track from the center of their formation before opening, so they need more time space before and after their exit. If everyone is exiting solo, it would be possible to write such a formula. That rarely happens at a commercial DZ. There are numerous solo's, 2-ways, 5-ways, 3-ways, all-size ways, etc. -- not to mention flatflyers compared to free-flyers -- exiting on any jump run. I believe the 45 degree rule is useful, but when there are very large groups (15-ways) that may be tracking in layers, even the 45 deg. rule may not allow for enough separation. The tendency for most people is to exit too soon after the group before them. We should all err on the side of safety (waiting) even if the pilot has to go around. Dave

------------------------------------------------------------ Chris, How about Tues. or Thurs. afternoon? I can be at Crosskeys by about 1 PM, weather permitting. Send me a PM if you like. Dave

My first BASE was the same way..My first Solo in a plane the same way. It takes a EVENT outside of what I EXPECT to scare me. A "normal" skydive never did. Low pulls...Yes. Mals...Yes. Some jackass in freefall 10 feet from my canopy...Yes. Some jackass cutting me off on final...Yes. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ron, OK.....doesn't the possibility that any of these things could happen on any given skydive create some apprehension? I would think so. I believe many people on this thread are talking about the same thing, but some are calling it "fear".....others not. --------------------- Skydiving is an extreme sport like Class V white-water kayaking; skiing the double-black diamond runs; deep sea scuba diving; or rock/ice climbing. To survive in extreme sports requires athleticism, coordination, judgement, knowledge, and courage. Someone once said, "There can be no courage if there is no fear." I agree. Dave

It's going to be 5000ft jumps. ~~~~~~~~~~~~~~~~~~~~~~~~~~ Chris, I'm basically a low-time jumper, but I have done a few heli. jumps. I'd recommend wearing a FF suit if you have one -- you'll be able to get stable sooner after going out at 5G because the suit will provide more air resistance. If you're sure you'll go to 5G this shouldn't be an issue....but what if cloud ceiling is low and you jump at 3G? I once did a heli. jump from 3G in shorts and a tee shirt and didn't get stable soon enough for me to pull at a comfortable altitude. Canopy was out by 1,600 though. Since then, I never do balloon or heli. jumps without a FF suit on. If the heli. is going forward at 60+ knots, it doesn't matter as much because the forward movement of the heli. allows you to catch air right away. Have fun! Dave

Pedro, Skydiving very risky. But consider: some people have 10,000 or 15,000 jumps and were never seriously injured. How can that be? Is their luck going to run out soon? Short answer: They are VERY careful! We can do things to minimize our risk (and they really work, when applied properly). Dave

Syn, Kudos! You started a very thought-provoking thread -- it appears to have stimulated some serious introspection. Skydiving isn't the only very dangerous "extreme sport," in fact, scuba diving, white-water kayaking, and rock/ice climbing may be even more dangerous. I find participants in those activities to be very similar to skydivers in psyche and character. They often think the same thoughts and ask themselves the same questions you have raised. In my profession, I am forced to deal with illness and death -- usually from serious diseases such as cancer, but sometimes from trauma. Trauma deaths commonly occur in young people and are usually very unexpected. I believe death is Nature's way of reminding each of us of our own mortality. It forces us to stop and look at our daily thoughts and lives in a different, better way. We consider what is important to us in life. Skydiving is a similar reminder, because you realize a serious mistake unanswered could be fatal. A mis-step in skydiving isn't like mishitting the ball in a tennis match with a friend...no serious consequences there. So...why do we do it? Why take the risk? For the excitement; the physical and intellectual challenge; the emotional high; the friendships; the fun; the travel; the beauty; the scenery; the sensory overload; the experiences unique to a two or three mile freefall -- with friends. All these and more. Participating in sport skydiving is an experience only a few people on the planet ever indulge. But what an experience!! When I did the 30,000 ft skydive at the WFFC last August, I felt it was an experience of a lifetime. And so it was!! In Antoine de Saint-Exupery's fable of THE LITTLE PRINCE a child of the royal family of a tiny planet visits Earth to seek the meaning of life. He fails to find it with his eyes, so he begins asking others where to pursue his vision. No one has the answer until a wise fox tells him: "It is only with the heart that one can see rightly. What is essential is invisible to the eye." Follow your heart, Syn. You've got to trust your instincts even if they go against reason. Dr. Alfred Adler once said, "The chief danger in life is that you may take too many precautions." How true. Blue ones, Dave "The meaning of life is adventure." --Alfred North Whitehead

Dan, this question comes up all the time in various DZ forums and you'll get as many opinions as there are well-intentioned JM's, AFF instructors, and "experts." None of the usual advice helped me when I had this problem at about jump #10. It is difficult for someone with 1,000-5,000 (or more) jumps to relate to this problem because stability for them while flat-flying is as natural as breathing for you. In very inexperienced skydivers (under 10-20 jumps), flat spins can be so rapid and violent that the jumper may lose consciousness -- the high centrifugal force caused by the spin disturbs normal body blood flow. This may be more common in static line students because they don't usually jump closely with others on their first few skydives. A few suggestions you'll hear: (1) go into a track and the spin will stop; (2) hit your heels or feet together to be sure a knee is not down; (3) keep your arms where you can see them -- are they symmetrical? (4) breath slowly, relax and arch more; (5) have someone watch or video you in a spin to see what is happening. There is certainly merit to all of these, but if you're a beginning jumper, it is almost impossible to go into a track or see where your body parts are while in a violent spin (3 or 4 revs per second). Moreover, it will be difficult for others, even on a slo-mo video, to see what is happening. (Been there, done that.) In addition when you're in the spin, it has been my experience your body has a tendency (without your awareness) to flex sideways toward the spin which aggravates it. I consider myself a low time jumper, but I can tell you what worked for one person from personal experience: pull your arms and legs in for one or two seconds, then open up again and assume a relaxed arch. I believe the main reason this works is because you are totally resetting your body parts and repositioning whatever it was that caused the spin. It has been suggested to me that this could increase the spin rate because of "preservation of angular momentum." (Think of an ice skater in a scratch spin pulling in his arms.) In actuality, I know that doesn't happen --- but I'm not sure why. The possible explanation may be that you don't stay tucked for long enough time for that effect occur, and when you restore the normal "flat-fly" box position, the wind resistance stops your turning. Hope this info is helpful. In a very short time you'll look back on this problem and wonder how it happened at all. Bl. sk. Dave