pccoder 0 #26 March 20, 2004 I hear ya. PcCoder.net Quote Share this post Link to post Share on other sites
USPA 0 #27 March 20, 2004 Hmm.. slept now and come to think of it you're right. My theory only stands when you're not on terminal velocity. But that leaves me with 2 questions: 1) Does blood go to your head? 2) If not, why?The trouble with skydiving; If you stink at it and continue to jump, you'll die. If you're good at it and continue to jump, you'll see a lot of friends die... Quote Share this post Link to post Share on other sites
piisfish 135 #28 March 20, 2004 QuoteTherefore, "your stomach goes into your throat." I had that on my 1st tandem... and I'm quite sure I'm not the only one in that case...scissors beat paper, paper beat rock, rock beat wingsuit - KarlM Quote Share this post Link to post Share on other sites
Fireflyer 0 #29 March 22, 2004 QuoteThe only "dropping" sensation that I have experienced in this sport is "dropping" all my cash into the manifest cash drawer each weekend....... i second THAT Quote Share this post Link to post Share on other sites Fireflyer 0 #30 March 22, 2004 QuoteThe plane is already moving us forward at nearly 100 mph, so the downward transition is gradual and pretty much imperceptible. stick your hand out of your car window at 60 mph. it gets slammed back pretty hard. if you exit right, you surf that oncoming wind right on down... nuff said... Quote Share this post Link to post Share on other sites JohnMitchell 14 #31 March 22, 2004 Another way to look at it, is that you are weightless during Freefall, and so is your blood.Nope, you are only weightless for those first few seconds when you leave a balloon, base jump, or cutaway from a slow malfunction. In regular freefall, whether on your head or belly, your are laying on a cushion of air, and weigh the same you would laying on a bed. If you belly fly, then kick over into a rag doll dive, you'll feel kinda weightless for a few moments while you accellerate, just like that funny feeling when the elevator starts down. Once you're up to speed, everything feels normal even though you're still dropping. Also, when you first jump out of an airplane, although you don't feel weightless because of the relative wind (you're already going about 100 mph across the sky when you exit), your gravity vector is not pointing straight down at the earth, but actually out in front of the airplane, explaining why formations fly "on the hill." If you were to take that clear, water filled space ball on your jump, you'd see the water rush forward on exit, as the wind accellerated you backwards, just like you slam forward when someone slams on the brakes in a moving car. I love the physics of this sport. There's a lot to it. Quote Share this post Link to post Share on other sites
Fireflyer 0 #30 March 22, 2004 QuoteThe plane is already moving us forward at nearly 100 mph, so the downward transition is gradual and pretty much imperceptible. stick your hand out of your car window at 60 mph. it gets slammed back pretty hard. if you exit right, you surf that oncoming wind right on down... nuff said... Quote Share this post Link to post Share on other sites
JohnMitchell 14 #31 March 22, 2004 Another way to look at it, is that you are weightless during Freefall, and so is your blood.Nope, you are only weightless for those first few seconds when you leave a balloon, base jump, or cutaway from a slow malfunction. In regular freefall, whether on your head or belly, your are laying on a cushion of air, and weigh the same you would laying on a bed. If you belly fly, then kick over into a rag doll dive, you'll feel kinda weightless for a few moments while you accellerate, just like that funny feeling when the elevator starts down. Once you're up to speed, everything feels normal even though you're still dropping. Also, when you first jump out of an airplane, although you don't feel weightless because of the relative wind (you're already going about 100 mph across the sky when you exit), your gravity vector is not pointing straight down at the earth, but actually out in front of the airplane, explaining why formations fly "on the hill." If you were to take that clear, water filled space ball on your jump, you'd see the water rush forward on exit, as the wind accellerated you backwards, just like you slam forward when someone slams on the brakes in a moving car. I love the physics of this sport. There's a lot to it. Quote Share this post Link to post Share on other sites
CanuckInUSA 0 #32 March 22, 2004 Quotestick your hand out of your car window at 60 mph. it gets slammed back pretty hard. if you exit right, you surf that oncoming wind right on down... nuff said... I love it when a 38 jump ????? tells me what it's like to exit from an airplane. Sorry if I sound a little testy here, but I never said what you quoted me as saying. Try not to worry about the things you have no control over Quote Share this post Link to post Share on other sites
USPA 0 #33 March 22, 2004 see my discussion with billvonThe trouble with skydiving; If you stink at it and continue to jump, you'll die. If you're good at it and continue to jump, you'll see a lot of friends die... Quote Share this post Link to post Share on other sites
Fireflyer 0 #34 March 22, 2004 QuoteQuotestick your hand out of your car window at 60 mph. it gets slammed back pretty hard. if you exit right, you surf that oncoming wind right on down... nuff said... I love it when a 38 jump ????? tells me what it's like to exit from an airplane. Sorry if I sound a little testy here, but I never said what you quoted me as saying. take it easy big guy! i am sorry i didn't click rickfri59's initial post to which (I know) that's where that comment was initially posted. i just didn't feel like backing the browser up and used your link as I saw you commented on the original thread too. at what jump number do you start thinking your opinion is more correct? would i have more credibility than my 38 jumps allows if i told you i have a degree in physics? prolly not eh? Quote Share this post Link to post Share on other sites
CanuckInUSA 0 #35 March 22, 2004 Quoteat what jump number do you start thinking your opinion is more correct? Some people have more natural freefall talent than others, some people have more natural canopy control skills, and some people have experienced more in this sport due to doing different and/or specialized training as well as experienced more because they have travelled to different DZs. Jumps numbers are nothing more than numbers. They show that you have a certain amount of experience, but they do not show what sort of talent or knowledge you may have. Obviously people are allowed to express their opinions here (heck I've spent more than a lifetimes worth giving my two cents around here), so I'm not against people talking about their experiences and/or knowledge. So don't confuse me as one of those people who will say you need X number of jumps before you are allowed to say anything. But when I wake up groggy on a Monday morning and read something about a newer skydiver telling me what it's like to exit from an airplane in a context that it sounds like they are directing the comments to me, I take notice. Don't worry dude ... no harm done ... Try not to worry about the things you have no control over Quote Share this post Link to post Share on other sites
billvon 2,394 #36 March 22, 2004 >1) Does blood go to your head? I think it does, but it's a pretty minor effect. It's not even like standing on your head, it's more like lying down, since when you are really in 'freefall' (i.e. not at terminal yet) gravity is reduced, so your heart doesn't have to work hard getting blood to your head _or_ your feet. Quote Share this post Link to post Share on other sites
Reginald 0 #37 March 23, 2004 I felt a falling sensation 2 times. The first couple of seconds out the door on my first tandem and on Helicopter jumps. I don’t feel a falling sensation anymore going out the door on a plane. Boy did I ever feel it going out of a helicopter, thought! A falling sensation is created by acceleration. The falling sensation is the same effect (although perceived slightly differently) as acceleration in a car. Picture this debate in terms of acceleration in a car. If you step on the gas you might feel the acceleration. Once you get to a constant speed there is no feeling of acceleration. So in any case you would only feel liked you are falling for the first few seconds of a jump. If you accelerate slowly you won’t feel anything. I believe the poster is correct about downward acceleration being slowed down going out of a plane because of the drag caused by the forward wind. In a helicopter you don’t get this and hence the feeling of falling. I would think there is enough downward acceleration going out of a plane to get some sensation of falling but experienced jumpers probably don’t notice as much as newbies since they are desensitized to it. Or I could be full of ****."We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP Quote Share this post Link to post Share on other sites
relyon 0 #38 March 23, 2004 Quote... The only time you don't get this is on helicopter, balloon and BASE jumps, since you don't have much drag to cause that acceleration. I've noticed it on cutaways too. Bob Quote Share this post Link to post Share on other sites
JohnMitchell 14 #39 March 23, 2004 QuoteQuote... The only time you don't get this is on helicopter, balloon and BASE jumps, since you don't have much drag to cause that acceleration. I've noticed it on cutaways too. BobYep, but you got more cutaways than most people have jumps, don't you? Quote Share this post Link to post Share on other sites
JohnMitchell 14 #40 March 23, 2004 Quotesee my discussion with billvonYes, I was reading the exchanges back and forth. That's where I scammed the idea of the water in a clear ball demonstration. I also agree with that guy who said that the blood does rush to your head, but your so amped you just don't notice it. I know I am. Quote Share this post Link to post Share on other sites
nael 0 #41 March 24, 2004 QuoteI felt a falling sensation 2 times. The first couple of seconds out the door on my first tandem I have only done one tandem and I felt like I was falling for the first couple of seconds too. Can anyone explain why that is? Has it got something to do with being nervous?www.TerminalSports.com.auAustralia's largest skydive gear store Quote Share this post Link to post Share on other sites
Erroll 49 #42 March 24, 2004 QuoteYou have nothing around you to gauge it with. When on a motorcycle you see the trees wizzing past If there were stationary objects in freefall then you would really get that falling sensation. I only get it if I go low. I have fallen past massive, thick and very high clouds on more than one occasion. All that did was to illustrate just how fast I was moving, having a stationary point of reference. It did not cause a 'dropping sensation' at all. I think the easiest analogy is the elevator. When it starts dropping your body (supported by your feet) starts going down with the elevator instantly, while your intestines follow a fraction of a second later. The same principle applies when the pilot gives you negative G's. Your body and your intestines do not move as one during initial acceleration and there-in lies the key. Rapid acceleration is the primary cause of the 'dropping' sensation'. In my opinion, of course. Quote Share this post Link to post Share on other sites
velvetjo 0 #43 March 25, 2004 Here's a stab at an answer from another perspective. I got my instrument rating last year, and the FAA's Instrument Flying Handbook does a pretty good job of describing how & why we experience spatial disorientation in instrument conditions. Some of the concepts seem to apply here too. Sorry in advance if I screw any of this up, it's from memory. First, the body maintains spatial orientation in 3 ways: vestibular, postural and visual. Vestibular orientation refers to the semicircular canals in the inner ear, which sense the movement of fluid and interpret it as turning movement in 3 separate axes. Postural orientation is the interpretation by the brain of forces felt on muscles, joints, and skeletal structure. Visual orientation is the brain's interpretation of a visual image. When these 3 senses disagree with one another, it's a trigger for spatial [dis]orientation, and some can be fooled easier than others. An example is an extended turn and/or altitude change in clouds initiated very slowly, so that the vestibular and postural cues indicate straight & level flight but the airplane is actually turning and/or climbing or descending. This is basically how a graveyard spiral occurs. There are several other examples of similar spatial disorientation illusions, but the important idea is that all of these types of orientation come into play. So based on all of that, my guess is that the absence of forward throw from the aircraft in balloon jumps, etc., may cause some people to have the dropping feeling due to the lack of postural cues (relative wind pressure in this case). I'd also guess that during a normal jump, all 3 senses tend to agree on the same orientation, which suppresses the dropping feeling. Any thoughts? Lance Quote Share this post Link to post Share on other sites
pajarito 0 #44 March 25, 2004 How does that work in the scenario of a person jumping off the high diving board? You feel the “falling sensation” due to what? By the way, what I’m referring to when I say “falling sensation” is described when you say “your stomach is going into your throat” or something like that. As far as the spatial orientation, vestibular, postural, and visual should all agree. My guess, earlier, was that the falling sensation was due to the anticipation of impact. In the case of a balloon jump where someone might experience the falling sensation, I would think that’s just the body’s natural reaction that is similar to one jumping off the high diving board. However, a skydiver just ignores it. Kind of like a free-climber ignoring the natural “panic” when he looks down from the rock. Some may in fact experience the falling sensation doing a regular jump out of an airplane. I don’t, however, I believe an earlier poster said that he experienced it doing a tandem jump. I really like your answer, though, and it makes sense. I’m a student pilot now and that is very interesting. What do you think? Quote Share this post Link to post Share on other sites
Fast 0 #45 March 25, 2004 QuoteHow does that work in the scenario of a person jumping off the high diving board? You feel the “falling sensation” due to what? By the way, what I’m referring to when I say “falling sensation” is described when you say “your stomach is going into your throat” or something like that. As far as the spatial orientation, vestibular, postural, and visual should all agree. My guess, earlier, was that the falling sensation was due to the anticipation of impact. In the case of a balloon jump where someone might experience the falling sensation, I would think that’s just the body’s natural reaction that is similar to one jumping off the high diving board. However, a skydiver just ignores it. Kind of like a free-climber ignoring the natural “panic” when he looks down from the rock. Some may in fact experience the falling sensation doing a regular jump out of an airplane. I don’t, however, I believe an earlier poster said that he experienced it doing a tandem jump. I really like your answer, though, and it makes sense. I’m a student pilot now and that is very interesting. What do you think? You are feeling the acceleration that your body is going through as you begin to move faster towards the water. Like said above the amount of "falling sensation" that you feels depends on the different vectors of movement and I would suspect at least minimally the degree to which you are prepared for the acceleration. The body notices it more when you have a sudden change in movement due to acceleration. Gravity is always acting on us, but as long as there is a force stoping it from moving us we do not accelerate. When the force is removed that prevents us from being moved we accelerate. If you are on a platform that gradually starts moving down with no jolts and slowly speeds up you wont feel the effects of it as much as if the platform suddenly droped out from under you. If there were no other cues such as being able to see that you were moving it would be hard to detect a very slow acceleration.~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
Reginald 0 #46 March 25, 2004 QuoteI don’t, however, I believe an earlier poster said that he experienced it doing a tandem jump.Quote Yeah, i just made it up because I like to lie to strangers on the internet. "We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP Quote Share this post Link to post Share on other sites velvetjo 0 #47 March 25, 2004 QuoteHow does that work in the scenario of a person jumping off the high diving board? You feel the “falling sensation” due to what? Yeah, I'd think that a high dive would be similar to a balloon jump for lack of postural cues - no relative wind force. I'm not sure how fear vs. acclimitization works into the equation, but it sure makes sense that they'd be factors too. Lance Quote Share this post Link to post Share on other sites livendive 8 #48 March 26, 2004 QuoteI think the reason you don't feel the same falling sensation like you do jumping off a 15ft diving board is due to the fact that there is no anticipation of impact. You're up too high. You know you're really not going to impact but your body instincts tell you that you might even though you're ignoring them. Therefore, "your stomach goes into your throat." That's my guess. As a TM, don't you get that falling sensation during the trapdoor? I certainly do (except on the occasional jumps in which there is no noticeable trapdoor, thanks to Insta-Canopy). Blues, Dave"I AM A PROFESSIONAL EXTREME ATHLETE!" (drink Mountain Dew) Quote Share this post Link to post Share on other sites gerrcoin 0 #49 March 26, 2004 I've seen some video of exits of students. In some you can clearly see the jumper kicking his legs. Aparently it's a fairly common thing in the first couple of jumps. The jumper isn't conciously aware of doing it. So I guess that there may be some sense of falling but most people are not aware of it because of the adrenaline or excitment, and then adjust to ignore it as they get more used to jumping.IMO.However when jumping from an aircraft there is already the sensation of pressure on your chest (if arched) which may fool the brain into thinking that the body is being supported, and as there is no visual cue of ground rush the sensation of falling may easily be ignored. On BASE, balloon or heli drops that pressure is no longer there. It's a theory anyway. Quote Share this post Link to post Share on other sites Erroll 49 #50 March 26, 2004 Quoteand as there is no visual cue of ground rush the sensation of falling may easily be ignored.. I disagree with fact that a visual cue is responsible for the 'dropping sensation'. (See my earlier post) about falling past clouds). An elevator in a high rise building accelerates quite rapidly from being stationary. Being inside the elevator, you have absolutely no visual cue, yet the falling sensation (your stomach in your throat) is very real. Quote Share this post Link to post Share on other sites Prev 1 2 3 Next Page 2 of 3 Join the conversation You can post now and register later. If you have an account, sign in now to post with your account. Note: Your post will require moderator approval before it will be visible. Reply to this topic... × Pasted as rich text. Paste as plain text instead Only 75 emoji are allowed. × Your link has been automatically embedded. Display as a link instead × Your previous content has been restored. Clear editor × You cannot paste images directly. Upload or insert images from URL. Insert image from URL × Desktop Tablet Phone Submit Reply 0 Go To Topic Listing
velvetjo 0 #47 March 25, 2004 QuoteHow does that work in the scenario of a person jumping off the high diving board? You feel the “falling sensation” due to what? Yeah, I'd think that a high dive would be similar to a balloon jump for lack of postural cues - no relative wind force. I'm not sure how fear vs. acclimitization works into the equation, but it sure makes sense that they'd be factors too. Lance Quote Share this post Link to post Share on other sites
livendive 8 #48 March 26, 2004 QuoteI think the reason you don't feel the same falling sensation like you do jumping off a 15ft diving board is due to the fact that there is no anticipation of impact. You're up too high. You know you're really not going to impact but your body instincts tell you that you might even though you're ignoring them. Therefore, "your stomach goes into your throat." That's my guess. As a TM, don't you get that falling sensation during the trapdoor? I certainly do (except on the occasional jumps in which there is no noticeable trapdoor, thanks to Insta-Canopy). Blues, Dave"I AM A PROFESSIONAL EXTREME ATHLETE!" (drink Mountain Dew) Quote Share this post Link to post Share on other sites
gerrcoin 0 #49 March 26, 2004 I've seen some video of exits of students. In some you can clearly see the jumper kicking his legs. Aparently it's a fairly common thing in the first couple of jumps. The jumper isn't conciously aware of doing it. So I guess that there may be some sense of falling but most people are not aware of it because of the adrenaline or excitment, and then adjust to ignore it as they get more used to jumping.IMO.However when jumping from an aircraft there is already the sensation of pressure on your chest (if arched) which may fool the brain into thinking that the body is being supported, and as there is no visual cue of ground rush the sensation of falling may easily be ignored. On BASE, balloon or heli drops that pressure is no longer there. It's a theory anyway. Quote Share this post Link to post Share on other sites
Erroll 49 #50 March 26, 2004 Quoteand as there is no visual cue of ground rush the sensation of falling may easily be ignored.. I disagree with fact that a visual cue is responsible for the 'dropping sensation'. (See my earlier post) about falling past clouds). An elevator in a high rise building accelerates quite rapidly from being stationary. Being inside the elevator, you have absolutely no visual cue, yet the falling sensation (your stomach in your throat) is very real. Quote Share this post Link to post Share on other sites
