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By rallyant
#17684
Our club held a water landing night to try and prepare us in case we ever have to make an emergency water landing.
of the 16 of us that had a go, 10 "died" and had to be saved by the divers.

Not the best quality pics but i thought id share them with you.

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Glen
Last edited by rallyant on Wed Aug 01, 2007 9:36 am, edited 1 time in total.
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By xerxes
#17685
Wow, I'm glad that's not my glider. I'm guessing most folks coulden't get out of the harness in time. Personally, if I'm underwater I'm cutting my way out. Looks like fun though!
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By boarini2003
#17688
What a great idea. Can you discuss with us, what were the leading propblems leading to death?
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By designbydave
#17689
That is AWESOME! And at a public pool? Nice Hang Gliding promotion guys :thumbsup:

Please do share the procedure for surviving a water landing.
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By rallyant
#17695
One of the guys there actually did land about a mile out to sea not to long ago, very nearly died from it.
I always thought id cut myself out too. but after that night im not so sure.

It only took me 15 seconds from the time i jumped of the edge until i was out and breathing again, it wasn't long but it was worse than i thought, I did not take a breath before i went under, i wanted to make it realistic/worst case scenario.
I fumbled getting my shoes threw the legs loop, a knife here might have helped, but you would still have to find and get your knife onto them after unbuckling and unzipping.

Another method used was unhooking, but the harness floats quite well. something i had not thought about, and it makes everything harder regardless of the method used.

last year they tried the knife and used string, but just as many "died"

The main thing is to get as prepared as you can before you hit the water, IF you get the chance.
Unbuckle, unzip, get your shoes off?, cut the hang straps and fall the last X feet to the water or fly in the A frame and climb right out the harness all together. depends how much time if any you have.
But we all agree, DONT land in the water :) or if you must, head out past the breakers and land in the calmer water.
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By gerg
#17696
Ditto! That is indeed awesome! Glad someone decided to sacrifice their glider for the cause... :shock:

I'm not surprised by the low number of "survivors"... But please do share any tips/techniques used...

E.g. did you guys have the chance to cut your way free? (lots of old hang straps?) or was it just get out of the harness or undo the carabiner? I'm trying to imagine how I'd get out with my pod harness.

EDIT: Well, looks like you answered a lot of the questions.. :) Thank you!
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By rallyant
#17697
designbydave wrote:That is AWESOME! And at a public pool? Nice Hang Gliding promotion guys :thumbsup:

Please do share the procedure for surviving a water landing.
thats what i thought. unfortunately they give us the pool space in the off season when theres almost no one there :(
boarini2003 wrote:What a great idea. Can you discuss with us, what were the leading propblems leading to death?
I think panic was probably the biggest problem. Following that, it was shoes getting stuck on the Leg loops .
With no shoes and bare legs, once you were unzipped, unbuckled and arms clear its simply a matter of swimming forward and out. But with pants and shoes you really need to relax, grab the loops with your hands and remove one leg at a time.

With a single surface glider like we ere using there is plenty of space under the wing for quite a while, so you could take a breath if in calm water, but to make it realistic i pretended i was in a double surface glider.

the other thing that struck me was how DAM hard it was to pull that glider from the water! there is NO WAY with all of us pulling we would be able to get the glider with pilot up. it was VERY hard to lift until the wing surface had separated from the water.
I now understand why people have died just walking along the beach with there gliders, to close to the water.
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By rallyant
#17700
gerg wrote:Ditto! That is indeed awesome! Glad someone decided to sacrifice their glider for the cause... :shock:

I'm not surprised by the low number of "survivors"... But please do share any tips/techniques used...

E.g. did you guys have the chance to cut your way free? (lots of old hang straps?) or was it just get out of the harness or undo the carabiner? I'm trying to imagine how I'd get out with my pod harness.
It was an old glider that has not been used for a LONG time. not worth using again these days.

I was not there, but im told that last year they had the chance to cut themselves free, they used rope instead of hang straps. But they were no more successful.

One of the other survivors on this night undid the carabiner to escape, I will have to ask again, but the comments i remember were that the fact the harness floats so well it was hard to turn over and find the carabiner, and even once free of the glider its still difficult to get out of the harness
sg wrote: When you said the harness floats which makes it harder, in what way?
Do you get pinned under the sail via floatation???

What method of escape did the survivors use? Was there a pattern???
At the start of the night i had planed in using the unhook method, but it was noted that the harness did float and pin you up against the sail/keel, so rather than take my chances fumbling for the carabiner i decided to just get out of the harness. Even then, because of the floating harness you are doing this in a head low - feet hi( against the keel) position. The harness just flows your shoes and grabs there every move.
Try putting your hand in a plastic bag underwater and pulling it out, if you can imagine?. It has this kind of effect.
I dont know if all harnesses would be like this tho?

Only 1 of the survivors used the unhook method, im not sure what most of the others did tho. good question. i will have to find out. or maybe this is a good time to get them on this forum :)
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By boarini2003
#17704
Very interesting discussion. Back in Guatemala I witnessed many water landings at Lake Atitlan where the LZ is pretty tight. Novice pilots would fly wearing shorts, easy to take off shoes and most importantly, an inflated inner tube tied or taped to the crossbar and control frame junction on the underside of the wing. This was enough to keep the wing afloat. It sounds crazy but it worked. So well in fact, that there was a student whose first mountain flight was done at this site. He was told to just fly straight out into the lake, while a boat followed closely under him.
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By axo
#17707
Ok... i guess someone else must have thought about this.. so i don't see why you were not using this simple system.

Enter the SNORKEL . :mosh:

If there is people flying near water, and the risk of landing on it exists... then why not discretely adapt a 2 or 3 feet piece of plastic or rubber pipe that goes from the kingpost through the hole in the sail down to anywhere at reach of the head of the pilot??? This would give the pilot a way to do things without getting so desperate for air, and in real life conditions, i bet you will not land on clear water like that pool, but a lake or the sea where you can't see much of what you are doing.

Here is an example.
Looks like it is lunch time for someone else!!
:owned:
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By xerxes
#17709
Sweet, that's awesome. You could even use one that has one of those valves at the top to keep water out of the pipe. :rofl:

This just reminded me of something I once heard: If your using a long piece of tubing as a snorkle, make sure to breath IN through the pipe, and OUT through your nose, into the water. If you exhale through a long enough pipe, there can be enough room in it to contain an entire lungfull, so you would just be recycling your depleted air, and pass out.
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By tony7kp
#17710
axopro wrote:Ok... i guess someone else must have thought about this.. so i don't see why you were not using this simple system.

Enter the SNORKEL . :mosh:

If there is people flying near water, and the risk of landing on it exists... then why not discretely adapt a 2 or 3 feet piece of plastic or rubber pipe that goes from the kingpost through the hole in the sail down to anywhere at reach of the head of the pilot??? This would give the pilot a way to do things without getting so desperate for air, and in real life conditions, i bet you will not land on clear water like that pool, but a lake or the sea where you can't see much of what you are doing.

Here is an example.
Looks like it is lunch time for someone else!!
:owned:
anyone who scuba dives / snorkles can tell you that this wouldnt be very feasible. In order to have a snorkle that goes to the top of the sail, you will need a pretty long piece of tube. And there is a limit to how much air the human lung can take in and out, which limits the length of the snorkle to only a foot or so. there is also limitation on the diameter of the snorkle, but thats not a problem here. But either way, with a tube that long, you'll be able to get about 1 breath of air, then you'll be breathing in your co2 from then on, which won't really help. so its good for one extra breath. that seems pretty pointless. if you're really worried about water landing, you can buy an emergency air kit which is the size of a small camera or so, and it'll be enough to give you air for the time to escape. Also it'll be much easier than trying to fit a snorkle system into your glider.
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By steve555
#17718
That’s awesome!
I’ve always wondered what that would be like. :shock:
I’m not sure what would scare me more, a tumble or a water landing.

Apparently my instructor and his friends had to do water landings during a demo in down town Pittsburgh at the regatta festival. He said they tucked floats up under their wing tips so as not to lose their gliders. When I asked about change in glide performance he said that (to the best of his recollection) there really wasn’t any noticeable difference.

As far as the snorkel idea goes it would be worth it to put it on there just to see the look on other pilots faces after they ask “dude what’s that tube for”. :mrgreen:
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By PilotGuy
#17720
You don't need to worry about the length of the snorkel, you're not going to suffocate yourself by breathing in and out of it.

The average male lung capacity is 6 liters, of which you can inhale and exhale 4.5 liters at a time. If you had a 1 inch diameter tube, which is a pretty generous size and about the max you can comfortably get your mouth around, your snorkel could be 28 feet long before you'd completely fill it with your own air. So a 5 or even 7 foot tube up to your kingpost would be no problem, you'd rebreathe a little bit, but still get fresh air. And even if you were rebreathing, it takes a while for recycled air to reach toxic levels of CO2, and you only use 25% of the oxygen in the air with each breath. And besides, you're not going to be hanging out under your wing, you're just going for a breath or two to get out of the harness and keep yourself calm. I say go for the snorkel.
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By tony7kp
#17723
PilotGuy wrote:You don't need to worry about the length of the snorkel, you're not going to suffocate yourself by breathing in and out of it.

The average male lung capacity is 6 liters, of which you can inhale and exhale 4.5 liters at a time. If you had a 1 inch diameter tube, which is a pretty generous size and about the max you can comfortably get your mouth around, your snorkel could be 28 feet long before you'd completely fill it with your own air. So a 5 or even 7 foot tube up to your kingpost would be no problem, you'd rebreathe a little bit, but still get fresh air. And even if you were rebreathing, it takes a while for recycled air to reach toxic levels of CO2, and you only use 25% of the oxygen in the air with each breath. And besides, you're not going to be hanging out under your wing, you're just going for a breath or two to get out of the harness and keep yourself calm. I say go for the snorkel.

although I say your math is correct, you are making wrong assumtions. when you have a tube that long, you have "dead air" trapped between the two ends of the tube and as the tube get longer, the more dead air you have. as you try to "clear" the tube, you will still have all that co2 that you are trapping. and if the tube is really long, you will just suck in 90% of that dead air thats now co2 back in. and even though you are also correct in using only 25% of the oxygen per breath, with that level of dead air, you will be out of breath and unconcious within a couple of breathes. the maximum length any snorkle should be to have no real dead air is approx 17inches, which is no where close to what you will need to reach the top of a glider.
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By xerxes
#17724
From Wikipedia:

"The maximum usable length of the snorkel tube is around fifty centimetres (twenty inches). A longer tube would place the lungs in deeper water where the surrounding water pressure is higher and the lungs would be unable to inflate when the diver inhales, because the muscles that expand the lungs are not strong enough to operate against the higher pressure.[citation needed] Snorkels also create what is called "dead air space." When the user takes in a fresh breath, some of the previously exhaled air remains in the snorkel and is recycled into the lungs, reducing breathing efficiency and causing CO₂ retention. The greater the volume in the device, the more this problem is magnified."

I think we need to add a solar powered air compresser and a regulator to the rig :lol:
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By axo
#17727
xerxes wrote: ... If your using a long piece of tubing as a snorkle, make sure to breath IN through the pipe, and OUT through your nose, into the water. If you exhale through a long enough pipe, there can be enough room in it to contain an entire lungfull, so you would just be recycling your depleted air, and pass out.

This is correct only IF you are using a LONG piece of tube with the capacity to contain an entire lungful as you said. I think it would be the way to do it in case of an accident with the glider. I was teach the opposite by a professional diver in Brazil in case you use the regular snorkel and you are using it in the sea.
The thing is that when water is shaky, moving and waving above you, the snorkel will get some water in it, so your lungs... at least that you blow hard and fast through the pipe and breath a deep amount of air and keep it on you a little longer, then again, blow fast and hard to get any water out of the pipe. Thats the way i did it and worked fine.


tony7kp wrote: anyone who scuba dives / snorkles can tell you that this wouldnt be very feasible. In order to have a snorkle that goes to the top of the sail, you will need a pretty long piece of tube. And there is a limit to how much air the human lung can take in and out, which limits the length of the snorkle to only a foot or so[

Wrong... first because as xerxes said you would only take air IN from the pipe and not OUT. Second we are not talking about a 10 foot piece of thick pipe going from the TOP of the kingpost down to the end of the A frame. 2 feet of pipe in between would be ok and being 1 inch thick or less can be enough to give extra time to unlock the carabiner or find the knife in one of the pockets in your harness. It wont be the easiest and smoothest way to breathe but thats not the point. You are not going to stay looking at the corals on a hang glider for such a long time right?

steve555 wrote: As far as the snorkel idea goes it would be worth it to put it on there just to see the look on other pilots faces after they ask “dude what’s that tube for”. :mrgreen:
Yes... so you can tell them that tube is to have an extra option to save your life in case of an accident and look at THEIR faces. If they laugh then they are the kind of people that fly and live their lives to show off to their neighbors what they got this month, and probably the ones that tried to go beyond their skills to show off and ended badly injured or fitting tight in a "nice and high performance looking" coffin.
If you use a clear pipe nice meticulously attached from behind the tubes to also not create more drag, I'm sure it wont really be much noticed to be there.

I believe the glider would start sinking at some point but the Snorkel Ultra 3000 XR could have made those 10 "dead" guys in the pool test to be a lower estadistic number.

Now i agree with the emergency air kit as well. I think i saw it somewhere before.

Fly safe!
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By PilotGuy
#17728
I agree that a snorkel in the usual sense of the word probably shouldn't be more than 20ish inches, because it does get damn hard to move your chest beyond that depth, but we're not worried about depth, we're worried about extending the time that you can remain below a few inches of water. So the assumption that a snorkel can only be 19 inches is incorrect because that is based on pressure, not on rebreathing the air.

However, if you base the rebreathing distance based on the volume of air that a person uses while sitting still and reading hanggliding.org, then the usable distance goes way down from the 28 feet I quoted before. OSHA recommends that people not spend more than 10 minutes in an environment of 3% or higher CO2. The average exhaled breath contains 5% CO2, and atmospheric air is very low, about 0.036% CO2. So if you exhaled 500 ml of air and only wanted to rebreathe half of that to keep yourself at around 2.5% CO2, your tube would be a maximum of 19.5 inches which just so happens to be the max recommended snorkel length.

But we're not talking about idle breathing, we're talking about big sucking breaths, during which you move 9 times more air than during idle breathing. 9 times 19.5 inches is 14 feet, half of the 28 feet I quoted earlier. 28 feet was the length of tube through which you'd be breathing nothing but your own air, with no fresh air coming in. 14 feet would mean half dead air, half fresh air, which would keep you at something like 2.5%, which OSHA says will give you a headache if you stay there for more than 10 minutes.

Chop that in half again, since you only need to go maybe 7 feet to the top of your kingpost, and you're breathing 25% dead air, 75% fresh air, for a CO2 concentration of perhaps 1.5%. Add to that the fact that like I said before, you're only taking what, maybe 5 breaths through this thing? Nowhere near the 10 minutes that OSHA recommends against for "worker comfort and safety". I think a snorkel would do more to keep you calm than keep you breathing. And if you still don't trust a few feet of snorkel, just breathe in through the tube and out in the water.

Either way, I still say go for the snorkel, if you feel like you need one.
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By PilotGuy
#17729
sg wrote:One thing that is not realistic about this simulation is there is no forward speed. When that control bar hits the water, the nose is gonna whack into the water sending you PRONE thru the control frame.
I think I would try to flare like normal and just drop into the water. That would give you the lowest forward speed and leave it up to you to decide the exact second that you'd take a big breath and go in. I think that trying to grab the trailing edge and pull yourself back might be a good plan, you're already going to be reaching and looking back to cut your main or unhook.

On a double surface if you're running out of time you might be able to unzip the bottom surface along the keel and find a pocket of air up inside the wing. Just poke your head up and smell the salty brine. :)
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By tony7kp
#17730
when breathing through a snorkle, even at a situation like that, its actually more dangerous to take such deep breaths. so you should never take the max breath under water and is suggested to only take in about half the breath. so your calculations should still be divided by half, but yes, it is still feasible but still not safe. but like its been said, this is probably for the last min resort from drowing so who cares. i still rather have an emergency air kit. i think its much easier and safer to carry if you are that worried about landing in water