Skydiving is the single most exciting sport there is. Nothing even comes close to the exhilaration you feel when floating on a cushion of air, and flying your canopy safely to the ground. It’s also very misunderstood, and filled with many common fallacies and misconceptions that keep most people from trying this beautiful sport. It’s heavily regulated by national organizations and in comparison to past decades and studying statistics, it’s surprisingly safe! To participate in it regularly, you’re required to obtain sufficient training and a license. It can be a long, expensive process to get your license, but once you do, the feeling of accomplishment is like no other. I highly suggest you try it at least once in your life.
Skydiving Myth: Skydivers pull a rip cord
Actually, rip cords pretty much went out with the round chute back in the early 1980’s. Skydivers using modern day “rigs” (the entire contraption of harness, container and canopies), throw out a pilot chute which is tucked into a pocket on the bottom of the container, just above your butt. The pilot chute is a small parachute attached to a “bridle” which is attached to the main chute. As the pilot chute is deployed, it catches the wind and pulls the closing pin which releases the packed main chute, pulling it from the container, so it will inflate… we hope. You can find a more detailed description of this process here.
There are some dropzones who still use rip-cord gear when teaching their students. Once they’re properly trained however, they graduate to the common bottom of container design. A reserve deployment does use a rip cord to activate the chute, but this is an entirely different design and we hope we never have to pull that handle.
Skydiving Myth: You can talk or yell to each other during freefall
Despite what you’ve seen in movies like Point Break and Cutaway, you cannot hear another skydiver during freefall. Perhaps if you were to yell into his year, you may hear a little but you certainly can’t have any type of conversation. The wind traveling past your ears at well over 100mph pretty much makes you deaf to all sounds. Additionally, it would be very hard to fight during freefall as well.
Skydiving Myth: When you deploy your chute, you go back up.
This is a common fallacy. One thing a skydiver cannot do is go back up. What you’re seeing when a skydiver deploys and goes up is an optical illusion. You’re actually seeing the videographer shooting the skydiver continue falling away from the one deploying who is obviously slowing down. By the way, that’s me you see deploying!
Skydiving Myth: If you’re ever knocked unconscious in free fall, you’re dead
Another common fallacy; it’s understandable how this could be perceived however. Think about it… if you’re ever knocked out by a mid-air collision with a fellow skydiver, who’s going to deploy your chute? Well, most skydivers jump with a device known as an Automatic Activation Device (AAD). It’s a small, air-pressure and speed sensitive unit that will cut the closing loop of your reserve chute so that it deploys automatically. They are usually set so that if you drop below 750 feet above ground level at over 78mph, it goes off. If you are unconscious, your landing will likely be rough and you may injure yourself or perhaps still die, but landing without any chute at all would be far worse. Some skydivers choose to jump without one because they are a mechanical device that can fail and possibly misfire, although they rarely do. The odds of it working when needed far outweigh the odds of it malfunctioning and deploying your reserve when you don’t want it to. You can read more about how these amazing units work here.
Skydiving Myth: Everyone falls at the same speed.
Despite what some people think, everyone falls at a different rate and the speeds will vary depending on weight (heavier people fall faster), body position and clothing (baggy jumpsuits slow you down, tight fitting suits go faster). The average terminal velocity in the belly down position is around 120mph. Some of the more advanced freeflying positions like “Head Down” or “Sit Fly” can push a jumper to over 200mph! Essentially the less amount of surface area to the wind, the faster you go. It takes a lot of work to contort the body in an arch (to speed up) and cup (to slow down) in order to catch up and stay with a group.
Skydiving Myth: A skydiver always packs his own chute
A good skydiver learns to pack his own chute early on in his/her skydiving career and continues to do so. However, there is no legal obligation to pack your own chute. There are trained packers who work at drop zones and will pack your chute for you. Generally the cost is around 5 to 7 dollars per pack. Many skydivers however, choose to stick to packing their own chutes because they know how they like it packed (there are small variations for smoother openings) and ultimately, who are you going to trust with your life? Yourself or some kid working the summer for 6 bucks a pack? If you choose to use the packer, be sure to tip them well!!
Skydiving Myth: You can deploy your chute at any altitude
I had an argument with a friend who was reading about military HALO operations, (High Altitude, Low Opening) and insisted that these military skydivers would freefall all the way down to between 100 and 50 feet then deploy their chute and land safely, this of course, is simply not possible. Freefall speeds can be anywhere from 100 to 160mph depending on varying scenarios; that’s over 170 feet per second! A good main parachute needs about 600 to 800 feet to open for two reasons. First, it needs to inflate. The cells are closed end and a great deal of air needs to fill the cells before the chute is operational. Second, it needs to opens fairly slowly to keep from injuring or even killing the skydiver. A hard opening chute can kill a person when they go from 120mph to 18mph in only two or three seconds. Hard openings are usually a result of packing error. Fatal hard openings are extremely rare but a ‘normal’ hard opening can make you see stars, and bruises! Minimum opening altitudes (as regulated by the USPA and CSPA) are 2500feet for A licensed skydivers and 2200feet for B, C, and D. Reserve chutes are designed to open much faster due to their necessity to do so quickly. [Image Source]
Skydiving Myth: You need to wear oxygen masks at very high altitudes
Only on the plane. Hypoxia can set in quickly at 18,000feet, so it’s necessary for planes to supply it when climbing to that altitude and beyond. The most common high altitude jumps are between 10,500 and 14,000 feet. Some larger drop zones with larger planes, will offer special “extra-high” jumps of 22,000 feet. This of course costs “extra-cash”. Some fancier planes offer masks, but more often it consists of a small hose coming out of the ceiling of the plane and you simply put it in your mouth up until you jump. Once you’re out, you’re only at that altitude for a short time, so extra oxygen on the jump itself isn’t necessary.
Skydiving Myth: The higher the altitude, the more dangerous the jump.
Actually it’s the opposite. Skydivers want as much altitude as possible. Not just for the extra freefall time, but also it gives us extra time correct a correctable problem that may arise. It takes about 1480 feet to reach terminal velocity (around 120mph). Whether it’s a 1500 foot fall or 15,000 foot fall, having a bad chute or no chute at all – the outcome is not going to be good. Ultimately, there is no “safer” altitude for a high speed impact. And considering the 600 to 800 feet it takes for a chute to open, I’ll stay above 3000 feet when I jump, anything lower would just be crazy!
Skydiving Myth: It’s possible to survive a terminal velocity impact
Everyone has heard the story: A skydiver jumped from 15,000 feet, his chute didn’t open and he landed in a muddy field and only broke his leg, or his back, or only ended up in a wheelchair, but he survived! There’s always something wrong with the story however. Many times it’s completely made up. But in almost all these cases, there was “something” out, meaning there was a tangled mess of a chute (malfunction) or both chutes (double malfunction – extremely rare!) trailing behind the jumper. This can slow your descent down considerably. An impact into soft ground or trees at 45mph is certainly survivable. You won’t enjoy it, but you have a better chance of survival.
Contributor: Skydiver
Muttley, (102), and Skydiver,
Firstly, Skydiver, thanks for a truly interesting ‘insider’ list.
Muttley, I immediately thought of that Lancaster survivor, which I knew to be true and verified. Unfortunately, I’d only read the outline details in passing, and decided not to post on that basis. Thanks for recounting the whole fascinating story. Appreciated by this particular pedantic aircraft history nut! It’s well known too that WW1 airman often chose to jump from burning and aircraft in pre-parachute days and die free-falling rather than be incinerated. There is even a photo of a German observer in a billowing trench coat alongside his burning biplane, but it may well be a fake, like various images of the era. So far as I know, there is no record of any such having survived TV. There is also a terribly graphic account in one of the air war autobiographies of a Hurricane flight commander ordering his pilots to switch off their intercoms. This was to shut out the terrible screams of one of their number trapped in the cockpit of his buring machine.
Spectating. Looks like I’m the only one so far who will comment on the pleasure of watching at air displays, etc. Curiously, observing this sport, although engrossing, is in many ways the opposite of exciting, except for the moment those tiny dots come hurtling out of the plane. It’s like flowers opening and then drifting down like plumed seeds, to draw similies from my own profession.
The other morning we were driving in the very clear, bright early light past the Chilean army camp in open mediterranean scrub terrain on the way in to Santiago. We noticed a largish prop. plane coming towards us quite low and in a straight line. Obviously nothing regularly commercial. Suddenly black dots detatched and a whole drift of khaki flowers began to float down into a cleared area. We and everyone else on the motorway stopped and drew into the hard shoulder to enjoy the free static-line spectacle.
It reminded me of something equally but infinitely less pleasantly memorable I witnessed on a Surrey heath about 40 years ago. This time I was driving along a British motorway, the M3, I think, in late evening autumn sunshine. I caught the loud sound of a very low-flying, large aircraft. Rather against the light I saw a Blackburn Beverly transport not many hundreds of feet up off to one side and heading in the same direction. Suddenly, our came the static-liners, with very little time between opening and landing. One dot just seemed to carry on at the same speed to the ground. I shook my head in disbelief. No, impossible .. I only thought I saw that. Morbid imagination. Next morning I read in the paper, “Yesterday evening, during a low-level parachute drop on ….. Common … Next of kin have been informed.”
Someone needs to go back to school. “speeds will vary depending on weight (heavier people fall faster)”. The force of gravity is the same on all objects regardless of mass and weight. The surface area of a heavy person is greater, providing more resistance, thus SLOWING THEM DOWN. No matter what you may think you have observed, what you “informed” us about is a complete crock of mathematical BS.
The only thing you leave out is Military. We do indeed go out low, static line I have been out at about 900ft. The highest I ever went out was around 1300ft this is normal, but since your main pulls out of the d-bag at the end of the static line it does not matter. The Military improved reserve parachute system (MIRPS) does indeed open fast (~100ft) I know this because they throw a dummy off the 250ft tower at Ft Benning and it is under full canopy well before it hits the ground. I have never opened one, and never seen one opened by someone who needed to, just chicken *****s who poped it after a twist or got drug on the ground. Plenty of injuries, mostly bad landings, people slip in the tub too. The most dangerous time for a military sky diver is before he clears the aircraft. If your reserve is accidentally deployed before you leave the aircraft you will most likely die and mash anyone in front of you into jelly as well between you and the door… The static line on it is at least 15 ft and the tower is only 250ft to the swing arm…. So to all you civilian *****s that have spent thousands to jump out of a cessna at 5000 feet I say you haven’t lived until you have stepped into the pitch black void with 160 pounds of crap strapped to you from the door of a jet aircraft travelling at around 120mph over uncertain terrain you can’t see in the company of 60 or so other unfortunate “volunteers” with more balls than sense.
Myth 9 “Perhaps if you were to yell into his year,” his year? wtf?
This might be a waste of electrons, since the point has been ignored so many times here, but:
“Heavier” people (denser people in the scientific meaning of word “dense”) fall faster than “lighter” (less dense) people. It’s mass vs. surface area applied against the approximately 120 mph relative wind created by falling toward the earth through the atmosphere. So: tall, *thin* people fall slower than tall *thick* people and *short* thin people fall faster than *tall* thin people. And a parachute deployed drifts to earth (Thank God) while a parachute inside its container falls pretty much like a rock (which will usually fall faster than a human of any shape, since it has no arms, legs or jumpsuit fabric to slow the fall).
I’m a relatively short, thick person and fall a LOT faster than some of my relatively short, thin friends.
Very very dense people (in the pejorative sense of the word) post knee-jerk negative statements without researching their facts.
Thanks again, skydiver. Great list.
125. Joe: Are you a plumber?
Skydiver- I am curious as to where you are… looks pretty flat. Florida, maybe?
Seque,
What gave it away?
122. mathemagician
For the 100th time… read post #110 and read the link I provide and stop trying to use grade 2 science to explain University level laws of motion.
“123. cmf
The Military improved reserve parachute system (MIRPS) does indeed open fast (~100ft) I know this because they throw a dummy off the 250ft tower at Ft Benning and it is under full canopy well before it hits the ground.”
No dispute there. Commercial reserves should open in less than 300 or so depending on whether it’s a high or low speed malfunction. B.A.S.E. canopies are designed to open just as fast as MIRPS, but the jumper isn’t falling at 178 feet/sec when they deploy… do the math, let’s say you jump out of a plane (not static line) at 1800 feet, you reach terminal velocity of 120mph (178ft/sec) with about 300 feet left. Now let’s say you deploy your MIRPS at 100 feet; This gives you .56 seconds to go from 120mph to nearly zero and stop from slamming into the ground. This would produce 10G’s of immediate jerk force against your body. Not at all survivable. Hop ‘n’ Pop’s and static lines don’t enter into the argument because speed on deployment is very low.
“127. Nicosia”
I am near Toronto, in Canada. It’s still pretty flat but not nearly as warm right now.
128. Joe: Seque, What gave it away?
****
Stab in the dark, Joe, stab in the dark.
thanks for the info. I’ve always thought about jumping but always wussed out. I feel a little bit safer with the idea now maybe I might go for a jump this summer.
Unless i wuss out
Alex-guitar4hire.blogspot.com
Nice list.
Having recently taken up skydiving myself it’s nice to see some of the myths dispelled. The knee jerk reaction of friends and family is expected but unwarranted. Once people know the training and focus on safety involved they can see most of their concerns are ill founded.
In response to the comments about it being expensive I have this to say; it may be expensive to work up to the first license but thereafter it isn’t TOO expensive. Once I have my license I can jump for £20 a time. I have some friends that smoke cigars and regularly send more than that up in smoke, others spend it on booze on a single night. If you want to try it but don’t want to spend a lot on something you’re not sure about then sign up for a tandem jump for charity, if you raise enough money you can get the jump for free.
Skydiving is fun, exhilarating, safe and well worth the money. Until you actually do it I find it hard for someone to comprehend what it’s like, the feeling is impossible to completely explain.
I don’t like heights but I’d rather skydive than climb a high ladder, people find this weird but I feel safer skydiving than climbing a ladder
grubthrower, On AFF courses you don’t have to jump with someone strapped to you or even in particularly close contact. In the UK the first few jumps are with instructors that jump out with you whilst holding onto your harness. They hold on during the freefall stage and let go just after you throw the pilot cute. If you progress through your first few levels quickly they no longer hold onto you. It’s worth getting past that for the experience.
The most common time you jump with some strapped to you is when you do a tandem jump which tends to be how most people start. I only did one of those for charity which got me hooked and I started the AFF course.
Equipment failures that require a reserve deployment up quite uncommon. One of my instructors has done over 7000 jumps and only had to pull the reserve once. Some minor equipment failures such as end cell closure can be overcome. AFF training includes extensive training on how to recognise and overcome these issues and is practiced in drills. From the very first jump you go up prepared and safe.
Skydiver: I too am near Toronto, Canada. Maybe I catered one of your functions?
Wow Skydiver, I can’t believe how much you’ve had to defend this list. I thought the DZ.com Forums were bad. This is ridiculous!
This list is featured on neatorama today! Thought someone should know.
Felix…. sorry but you are dead wrong and #6 is correct. I am a skydiver and I know it to be true. I can fly in a sit or headdown so “vertical” with way less drag and a big boy flying on his belly can keep up with me. Someone my weight and size could not do that. What your refering to is true but in a perfect vaccuum where wind and other factors do not play a part. If you are a small person and want to fly in a formation with other heavier skydivers guess what we do….. throw a “weight” belt on you which increases your fall rate.
I think everyone arguing the whole “weight issue” in freefall, are using the wrong arguements. I keep seeing “oh no, heavier people do fall faster because of wind resistance and such”. Well of course that would slow them, size, shape, and drag would all slow them, but the statement that “a heavier object falls faster” is ridiculous., drag and shape are completely different issue’s than weight, and as for the guy who stated the “archimedes principle” states that heavier people fall faster, thats silly too, as the archimedes principle relates to object traveling through a fluid, not air…AND it’s still reffering to size, shape and drag, not simply weight.
Oh, and BTW, Gallileo wasn’t standing inside a vacuum when he did his experiment, this isn’t just true in a vacuum. Everyone seems to be voicing their own arguement whether it relates to the original item in question or not, lol.
I had skydiving on my “bucket list” so last June 22nd I went out with a 21 year old co-worker and went through training and I was number 8 in line. Gave me plenty of time to “chicken out”. Couldn’t do that with all those youngun’s watching. By the time it was time for me to jump, it was dusk. I ended up with the prettiest time of evening to be able to see the horizon and lights forever. I jumped tandum but I would do it again today and hope to again sometime soon. I told no one, family or friends until afterward so they wouldn’t talk me out of it. It was the most awesome experience and I’m 62 years old.
Skydiver – Great list. I worked in skydiving full time for four years. I would always dread it when people asked me what the drogue parachute was for because inevitably I’d end up tryig to explain to them why it is a tandem falls faster than a solo. Dumb looks abound.
“there is no legal obligation to pack your own chute”
#5 is somewhat misleading in some places ( like Quebec Canada) you are legally required to have a chute packing license and if you don’t you have to have someone else with it to pack your chute.
139. rob
You’re right, it is a little misleading. I was actually informed by my rigger that this is also true in the US, however it doesn’t change the myth that only the person jumping the chute is the one who must pack it. I’ve bribed a few of my fellow jumpers with beer to pack for me.*
I added this as a myth because before I started jumping I used to hear and repeat “only YOU are allowed to pack your chute”. I had almost 20 jumps before I packed my own.
*Disclaimer – Skydivers do not drink and jump… ever! The beer light does not come on until the sun goes down…. and only if we’re not doing night jumps.
137. denm7510
*sigh* sorry but you’re wrong.
Let’s post this AGAIN! And please READ IT!!
http://www.glenbrook.k12.il.us/gbssci/phys/mmedia/newtlaws/efar.html
great list! I went skydiving last summer, got it as a gift, and would recommend it to anyone. I also enjoyed the parachute ride down, much more fun and softer than landing in a plane. I went tandem and got to pull the chute, but didn’t pack my own, the company I went diving with did it for me. It’s in a company’s best interest not to have injuries so they do what they can to make it as safe and as fun as possible.
I spent 3 years with the 82nd Airborne back in the 90′s and just managed to get in my 65 jumps (and complete Advanced Airborne School) and qualify as a Master Parachutist. Later did some sport jumping after leaving the Army, so I’ve seen both sides.
During Airborne School at Ft Benning, GA, the instructors would constantly pop off that jumping was “the best thing you could do with your pants on,” and were they ever right! The roar of the plane-a C141 Starlifter–was followed by the utter silence after the canopy opened. Never was I so happy as when I felt the tug of the chute opening and looked up to see a perfectly round canopy! My heartbeat had to be pushing 200 beats/minute all the way down (which from 1250 ft went way too fast). By the way, some of my classmates were petite women, and I saw a few of them FLOAT UP because they caught some thermal updrafts that very hot day (over 100 degrees F). Two jumps the first day, two the next, and a night jump to complete school and get our jump wings–a really great day!
Over the next few years I was fortunate to jump all over the southeastern US, in high deserts in Utah and California, in jungles in Panama, snow in Alaska, and just west of Cairo, Egypt. In daylight we’d jump at 750 feet, but they gave us another 250 ft for night jumps, supposedly for slower reactions at night. We’d even do fog and light rain as long as we had the final 100 ft clear so we could see the ground. We hit like a ton of bricks in those SMALL parachutes (just enough wind resistance to get MOST of you to the ground quickly without BREAKING any bones MOST of the time), but as my sergeants would say, “Any jump you can walk away from is a good jump.”
Sport jumping is COMPLETELY different. It’s all about fun. You walk to the plane, stroll back from the DZ, and at the end of the day have a hot shower and cold beer. I’ve been a scuba diver, whitewater rafter and mountain climber for years, but jumping is still the greatest thrill I’ve found. I heartily recommend that you try it at least once. Do a tandem jump or an accelerated free fall, but put your knees in the breeze the first chance you get!
Most Army jumps are night-time “mass tacs”: 6+ aircraft putting out jumpers as fast as possible and as low as possible because paratroopers are legal targets per international laws of war (but not pilots who bailed out).
My biggest jump was Operation Bright Star in November ’81; we flew nonstop from Ft Bragg, NC to Egypt and donnned chutes inflight without ever touching ground. After 12 hours in the plane we jumped and went right into a 20 mile tactical march. We were guinea pigs so the brass could confirm it was possible to fly us halfway around the world into a combat situation without using a forward staging base. I know it was the longest day of my life.
A friend was a platoon leader with the Rangers that combat jumped into Grenada in ’83; he told me they jumped at 500 ft with no reserves because there wouldn’t be enough time/elevation to use them if the main failed. (Another friend, Frank Hardy, USMA ’78, died in training HALO jump at Ft Bragg. RIP)
144. ex-paratrooper: What an exciting story! I’m sending it to my husband who is a retired Air Force Major, he was a navigator in the old C 130′s and the like. He’ll love your tale.
Thank you for your service to our country. My condolences on the loss of your friend.
Regarding number 2 on the list – “Altitude Dangers”.
Actually, at insanely high altitudes sky-diving can be lethal. At high altitudes there is a risk of going into a “flat spin”.
The USAF looked into this during the 1950s, resulting in Project Excelsior. See the Wiki article here: http://en.wikipedia.org/wiki/Project_Excelsior
Note that for most recreational sky-diving this isn’t an issue.
Very interesting list, especially ex-paratrooper`s story.
weight will not cause you to fall faster.
reduced volume will
streamlining of exposed surfaces will
never weight
there’s a typo on number 2. Year should be ear.
and apparently i quoted the wrong number. It’s on number 9. sorry!
Great list btw. We’re scheduled to go and skydive this summer. *whew*
I like this list, but while these myths are interesting, they are hardly “fascinating.”
You guys should really leave physics to the physicists, and reserve judgement until you have actual experience.
btw: Heavier, smaller people fall faster. PERIOD.
Terminal velocity landings don’t exist. It is not possible. PERIOD.
I think you should also add the myth that you get a “falling” feeling for the entire jump, when realistically, the feeling of acceleration fades to nothing as you approach the terminal velocity.
If you would like to speak to someone in person about skydiving, visit your local drop zone! An instructor will help you for sure. …and while you’re there, you might as well go skydiving!
RE: 77 Skiffo.
I have done two jumps. Both were not good form and I had to repeat 2 – which I did not do. I stopped at 2. So, you wanted to know how difficult it is to make yourself jump. After 8 hours of classroom work, I went up with 2 jump masters. When the door of the airplane opened at 12,500 feet, I froze – figuratively speaking. I could not move. So, I went back down – in the airplane. I later did jumps no. 1 & 2. I never went back even though I had a good friend with over 5,000 jumps. I would go and watch but I never tried it again. It did nothing for me, plus the cost as Skydiver has noted is very high.
Hope this helps.
For everyone that has a hard time believing weight does not matter as far as fall rate is concerned, lets try a thought experiment.
We have a feather. We make a perfect mold of said feather and fill the mold with lead. Now we have the real feather and the lead feather.
Both have the same surface area and both have the same volume(The volume of any solid, liquid, plasma, vacuum or theoretical object is how much three-dimensional space it occupies). The only difference is weight(using Mass as a measurement in this example is not appropriate since the mass of an object remains constant throughout the universe whereas weight is a function of gravitational forces and we are talking about skydiving on earth).
So, we have two objects whose surface area and volume are identical but their weight is different. Take these two object to the top of a ten story building and drop them off. Which do you think will hit first. Of course, the lead feather will.
And before anyone disagrees because it may be said “the real feather will be affected by winds variations so it’s not a true test”. I would say precisely. The real feather will feel the effect of the wind or “Terminal velocity” sooner than the lead feather because it weighs less. It will be more at the mercy of the wind because of less weight.
Remember the the two feathers are identical in every way except weight.
Also, if anyone doubts that I have no experience with skydiving and thus no experience dealing with jumping with people of different weights, here is my resume. Started jumping in 1999, I have nearly 4900 jumps and I am an instructor(static line, tandem master and accelerated freefall(AFF) instructor.
Yes, people do fall at different rates in an atmosphere(not a vacuum) because of weight.
to SkydivingInstructor
I’ll bet you $100 if you dropped two identically sized balls of identical dimensions but different masses–but both of SUBSTANTIAL mass–you would find the heavier ones does NOT fall faster. Drop for example, a lead ball (200 lbs) and a steel ball (100 lbs.). Galileo did this from a tall building with, I think, a wooden ball and one of iron, a few hundred years ago and they landed simultaneously. The substantial mass for both objects overwhelms the minor impact of wind resistance.
In the club where I did my sport jumps the fastest jumper was always this guy who was about 5’10″ and 170 lbs. He wore a tight fitting suit, kept himself tucked in, and really zoomed. He consistently fell faster than guys weighing 100+ lbs more.
To ex-paratrooper:
I’ll take that bet. Galileo performed no such experiment.
A biography by Galileo’s pupil Vincenzo Viviani stated that Galileo had dropped balls of the same material, but different masses, from the Leaning Tower of Pisa to demonstrate that their time of descent was independent of their mass. While this story has been retold in popular accounts, there is no account by Galileo himself of such an experiment, and it is generally accepted by historians that it was at most a thought experiment which did not actually take place.
Just like that apple that fell on Newtons head and how it proved gravity. Didn’t happen.
Galileo proposed that a falling body would fall with a uniform acceleration, as long as the resistance of the medium through which it was falling remained negligible, or in the limiting case of its falling through a vacuum.
So, as stated above, “as long as the resistance of the medium through which is falling remained negligible”. At a freefall speed of 120MPH the winds is not considered negligible, it is in fact a very strong force. If you drop two object from a short distance(say under 50 feet) then they will drop at ABOUT the same rate because they have not reach there full speed or “Terminal velocity”. (A free falling object achieves its terminal velocity when the downward force of gravity (Fg) equals the upward force of drag (Fd). This causes the net force on the object to be zero, resulting in an acceleration of zero.)
This is all high school physics and I have a hard time believing people still cling to these misconceptions. Also, all of this information is easy to look up on the internet if you have the time and are not to lazy.
Also in your example you state “the fastest jumper was always this guy who was about 5′10″ and 170 lbs. He wore a tight fitting suit, kept himself tucked in, and really zoomed. He consistently fell faster than guys weighing 100+ lbs more.”
This is all true and easy to explain.
A tight fitting suit creates less drag and therefore less wind resistance. You can also wear suits of different material types to create more of less drag. Go to any of the manufacturers web sites that sell skydiving jump suit, read the types of material and explanations.
Also, keeping yourself “tucked in” reduces your surface area which creates less drag which also has less wind resistance.
As far as your “guys weighing 100+ pounds more” is concerned, that’s easy to explain also. I am 5’6″ about 170lbs and have jumped with people that are about 6’3″ 205lbs. This person weighs more and fall slower but he had on a baggy suite(more drag) and had a lot more surface area than I did(Much taller).
As I originally stated, if you have two objects with the same surface area and the same volume, the heavier object will fall faster.
I’ll still take that bet. Prove me wrong with facts though, not anecdotal science or untrue story’s from century’s ago.
Nice description SkydivingInstructor.
ex-paratrooper, it’s been explained ad nauseum in this thread as to how this works. I’ve provided a link -twice- that explains the science behind it and why it works. Here it is again.
http://www.glenbrook.k12.il.us/gbssci/phys/mmedia/newtlaws/efar.html
Even if Galileo did perform that experiment from the Leaning Tower of Pisa, it’s only 182 feet high. Nothing of substantial weight can reach terminal velocity from that height. Two objects of different weight, dropped from 182 feet will hit the ground at almost the same speed, I say “almost” because the incremental difference of time between impacts would be so minute, it would be imperceptible to the naked eye, so it would appear they hit at exactly the same time. It’s pretty simple if you just read about it.
Now pay SkydivingInstructor his $100.
@ Skydiver
Cheers for that link!
I questioned it at first but reading through that helped understand why it happened. Come to think of it, i’d seen it before in Myth Busters where he lets a handful of pennies go in the air.
I take it these pennies would decelerate back to their terminal velocity (providing he was traveling at his TV) over time? Please correct me if i’m wrong
Great article btw! Still wouldn’t do it, I just know I’d chicken out
Kudos
#102 Muttley
You quote the “official” German document saying ““true in all respects,namely that he made a descent from 18,000 feet”
What a pile of poopoo. German military document stating any distance in something other than metric? Right.
Just looking, (158),
Instead of making a ***** of yourself trying to shoot down Muttley on a nit-picking technicality, why don’t you look up the huge amount of official data which supports the event? (As noted by Muttley, but ignored by smart-arse you.) Information provided by the Germans for British authorities would have been in translation and with data in current British standards anyway.
Here is something from the records of the club set up for those who owe their lives to parachute descent from aircraft:
“The Caterpillar Club.
RAF Sgt. Nicholas Alkemade, who during World War II bailed out of a RAF Avro Lancaster without a parachute and landed uninjured in a snow-drift, was refused membership because a parachute had not been used.”
So congratulations, Just looking. You’ve landed in your own pile of poopoo at TV without the bog-paper opening, and without surviving.
#50 video is sick!
also cool, dude that flew across the channel, mentalist!
#159 Anon. I mean, Muttley. It’s you, right?
You’ve provided less than nothing to prove the veracity of the story. Translated documents, especially official translated documents, NEVER substitute units of measurement. At best, there might be a note with conversion, not complete disregard for the original document’s numbers and units.
As far as “official” records for The Caterpillar Club, quoting wikipedia is NOT an official source. Try again.
No, I’m not Muttley, but from what I’ve managed to discover I support his post fully. He may not still be around to answer. If he is and does, I’ll leave you to him.
So the data about the Caterpillar Club is not correct because it came from wiki? So all the info presented by Muttley is wrong because you consider it so.
Provide conclusive proof of equal quality against the Alkemade incident and you’ve made your point. To challenge evidence you have to disprove it, not attack the presentation of those who state it. And that means disproving compound supporting evidence in this case, including from those who had every reason not to believe it themselves.
Or why not go visit his grandson at Loughborough and tell him his grandad was a *****ing liar?
If someone were to make a weak, poorly worded case for the Theory of Gravity and supported it with a quote from Wikipedia, you then claim the Theory is false, eh?
(Not that I’m implying Muttley’s case is poor, since I don’t even know where his source or sources came from. In fact, regardless of the ‘official’ German report, there are various reliable accounts in the English language which state his bale-out altitude at 18,000 feet.)
None of us accompanied Alkemade on his flight, his fall, or his landing. None of us knew him directly or indirectly, or have any first-hand knowledge of him or his circumstance. Pray tell us then, on what basis you reject the investigations of those who did and do (many of them technical experts), both at the time and subsequently?
Oh I get it. Of course. All those fellas realised there would be a Guinness Book of Records after the war ended. So the Gerries and the Limeys decided to cook up the story to get a good entry.
Or maybe you are still in your same pile of steaming, squire.
still just looking, (161),
I forgot to prefix your details on my reply to yours. When/if it comes out of moderation it will replace this as post Nº 162.
still just looking, (161),
ADDENDUM
“They also found the altimeter ‘fused’ at 18,000 feet – the height at which it ‘blew’ establishing a minimum height from which Alkemade could have jettisoned.” (That would depend whether the Lanc was falling by then, or still climbing, of course. Not that it would make the slightest material difference to Alkemade’s TV under the circs.)
Probably there’s “a note with conversion” to meters of the altimeter measurement in the official German language version of the incident, so fatboy Göring would understand.
Kindly suggestion: just stop posting still just looking.
Talking of TV without ‘chute. Can one of you experts put me straight on something?
Presumably you guys always operate over terra firma. But it has occurred to me it would be ‘better’ to free-fall over water than land, should the awful choice occur. Perhaps that’s a childhood memory legacy of seeing a muscular fairground fella dive from about 100 feet into a tiny barrel of aitch-two-oh! On the other hand water must surely be little different from a brick wall if you hit it at around 120+ m.p.h. To stand any chance of survival, your entry alignment would need to be absolutely mm perfect.
Is there any accepted record of this ever having happened?
164. Anon,
Your guess is right — at 120 mph (actually at a lot less speed, smacking water is about the same as smacking concrete. And to enter the water with a vertical body orientation also means you’re falling with the same vertical postion and thus, your fall rate is much higher than 120 mph. Either way, you’re pudding. If you could survive, you’d surely be unconscious, and (assuming you were skydiving and not just falling out of an aircraft) you’d be wearing your rig, which adds weight and limits mobility, so you’d probably drown (I can’t help but think of Butch and Sundance here).
165. Anon: I see that Joe has answered your question, but I’ll add something that might be a tad more tangible.
Consider the number of people who jump from San Francisco’s Golden Gate Bridge (much, much lower than the altitude of an aeroplane from which one would skydive), and the fact 1300 people have died in that fall, while only 26 have survived.
Joe, (166), and segue (167),
I didn’t have any but the most lingery of lingering doubts. Perhaps falling through the rigging and sails of an extremely tall-masted tea clipper might help!
Trying out mere air resistance of a sudden from a sports car or train travelling at 100 m.p.h. or so is pretty sobering.
However, to see what the human body can survive, try spending a little less time at LV and watch more ‘World’s Most Amazing Videos’ instead (joke). And those are only what have been captured as images. That’s what caused me to wonder.
It takes almost 1500 feet for a person to reach terminal velocity. If the likelihood of surviving a plunge from the Golden Gate is fatal more often than not, a terminal velocity impact would be even less likely. I’ve never heard of it happening either.
I do remember the story of a military paratrooper a couple of years back who, while under canopy, decided to show off for his wife and son while doing exhibition maneuvers at an air show. He thought it would be fun to cut away his chute at ten feet above the water he was supposed to land in. Depth perception over water can be very misleading and when he cut away, he was just a little over 100 feet above the surface; he did not survive the fall.
Skydiver,
A good motto for anyone in extreme sports could be: Showing off may gain you a Darwin Award!
By the way, I hope no one thought so, but under no circumstances was I intending to imply that anyone (sane) would be stupid enough to leave an aircraft deliberately at altitude with a view to diving straight into water and surviving.
In fact from what I’ve read about wartime survival parachute descents into sea, this is by no means a doddle. I believe it’s important not to let the ‘chute billow down on top of you if poss.
sure you can survive. I did – fractured pelvis and some SPECTACULAR bruising after my radio died, the wind came up and my chute didn’t quite deploy properly.
I chose not to land on the highway
or in the hydro lines 
and picked a field. A fallow cornfield. Hit with enough force that a dry cornstalk pierced right through my doc marten boot.
6 weeks on crutches.
never again – i admire people who skydive and do it well, but me? Never again.
loved the list and the comments that followed, learned some stuff. jumped 3 times static line. first time at the dz jump master asked what i thought, i said um ok. he looked at me amazed and said what do you think of *****? welll thats another thing. but it just didnt do much for me , jump out and float around oh well. should have continued because i know now free fall is where its at and some of the vidoes ive seen make me want to try again. cerified scuba, sorry too noisy, i prefer snorkel but thats just my 2 cents
I don’t remember if someone commented #3 (“You need to wear oxygen masks at very high altitudes”) but in some countries you must use an oxygen tank after exiting a certain height (e.g. >6000m in Sweden, and >9000m requires the jumper to breath pure oxygen 30 minutes before the plane takes of to get rid of the nitrogen in the blood). When you switch from the airplane oxygen to your own supply you must hold your breath: you don’t want that nitrogen.
So Skydiver, what are you jumping? Main, harness, etc.
Hi cat… I know a “cat” who skydives and lives in Australia. You don’t happen to be the same one I know from STI are you?
The oxygen mask one is, of course going to depend on various factors but I was referring to standard fun jumps that require no special permissions or circumstances. I didn’t know about the Swedish law, that’s interesting but seems a bit extreme to have oxygen on in anything other than the plane at that altitude.
I jump a 210 Saber2 and a Javelin container.
In regards to Jumping,HAHO,HALO,LALO I have done them all for many years, as far as HAHO all I can say is the sky(stratosphere) is the limit, and of course depending on your equipment ie; O2, heated suits etc…and you can glide onto your target many miles away undetected, for myself the farthest was 15km away,so you figure out the math lol… can’t say much else. As far a LALO it can be done at 300 ft but you must deploy your chute while standing on the ramp of a A/C ie (C-130) and let your chute drag you out. As far as basic standard military static line jumps are usually done at night at an altitude of around 1100 ft, but we have gone down to as low as 750 without any equipment ie rucksack etc…I have heard the Brits have gone as low as 550ft. Just some interesting fact, have a good one!!!
Felix, I thought that too, I thought physics would lead to teh same fall rate – not true. I’m a former tandem instructor and longtime skydiver. If you and I had the exact same body frontal area, fell with the same exact body position but I was 50 lbs heavier than you, I would fall measurably faster. Why do you think they have to use a drogue chute on a tandem rig? You have the frontal area of 1 person with the weight of 2. Trust me, if I had a hard time getting the drogue out, we started going real fast.
recommended reading: “Into The Silk’ story of the irwin(?)parachute company and the ‘Catapillar Club’. about the members who used a canopy to save their lives. it also talks of saves without a ‘chute. it also confirms Alkemades WW2 story but there is the added information that he went through fir trees that were on a STEEP SLOPE and burst out of a deep snow drift at the bottom breaking his nose and leg.
I weigh 70kg rigged up i am resonably tall. when i was doing 4 way dives with stocky heavier guys or gals i must wear weights to keep up other wise i tend to float in the formation. the speed difference is quite noticable as well as i get to my terminal speed earlier than them they keep accelerating for a couple of seconds longer dragging me along. on the other end on large group skydiving as the numbers build the formation it actually slows down and i have no trouble flying wide and not going below 30 plus jumpers in the formation. i just love to exit last and dive swoop flare and dock with a grin from ear to ear.
Ozzie
throwing myself at the planet (and missing) since 1975
what this guy is a tool i jumped a ripcord rig the other day… stupid stupid man
ffs your all completely insane jumping out of a perfectly good plane
Maybe I’m missing something, but the disagreements about whether people can live through falls from high altitudes are pointless. Clearly they have on very rare occasions, but it’s all about SURVIVABLE deceleration to a SURVIVABLE impact speed – whether by a parachute (partially or fully opened) or by an incredibly lucky sequence of events, such as falling through fir branches and then onto the edge of a snowdrift, etc.
No deceleration from terminal, no dice.
Nice list, Skydiver. Although I think you’re being a bit hard on packers and those who use them!