Article on High Altitude jumps

[chaoskitty 0]

I'm looking for an article on high altitude jumps. Risk, preparations, things that can happen that wouldnt normally happen on regular skydives.. etc.
Basically, trying to educate a low timer who wants to make a high alti jump.

[chuteless 1]

I don't know "exactly " what you are looking for, but Ive done about 6 HALO jumps, highest 36,916 during the day, and 30,571 during the night.

A word of advice ( based on an incident I witnessed) never ask the military for anything unless you intend to do everything totally in accordance with their type of training etc.

I once saw a letter to the Candn military, from a guy who wanted to do a HALO, and he said he had "scrounged" some equipment....WRONG WORD TO USE, he may have got it at a garage sale. His lettter was filed in the waste basket.

Find iout where you can get an HAI (High Altitude Indoctrination) course...they are available to the public. Military people could direct you.

You should have at least one ride in the altitude chamber...Ive had a dozen up to 43000 feet.

Ask military if they canm direct you to purchase a bailout bottle, and plan on a console supplying all on board the aircraft, with at least one person (experienced) with a walkaround bottle.

A good Oxygen mask is a MUST, with a good attachment to your helmet )again ask military...they have everything or know where a civilian can purchase it.

Best of luck to you.

Bill Cole D-41

[kelpdiver 2]

how high are you talking? 30? 24? 22? 20?

[chaoskitty 0]

21,000 feet. I'm just looking for some information to fwd to another jumper. Her instructors cleared her to make the jump. Shes very current but also very new. I just wanted to give her some info so she can make a better informed decision, and prepare herself, rather than just trusting its OK for her to do because her instructor said so.

[kelpdiver 2]

ah, that's a funny altitude. Much of the articles are really geared toward 30k jumps where demand regs and prebreathing is necessary. Some believe the same steps are necessary/prudent for 24k.

I did a 24k jump in a fast King Air 2 months back and it went very well. We just used the simple nose masks, started breathing from 6 or 7k. However, the affects of taking off the mask were instant and one two way couldn't count to 12s, waited nearly 30. That put me on a long spot and the three of us landed out. Airspeed is higher up there, so depending on the location, could be a concern. Temperature may also be, depending. Other than gloves, I was in standard gear. I keep forgetting to wear more than thin socks and running shoes.

In December I had a far less good jump, going to 18k in a slow climbing C206. I think we started on O2 at 12 or 13, and I was sharing my mask with another guy. And it was 45F on the ground. Perhaps -20 at full, same as my 24k jump. So I was getting hypoxic, lips getting a touch of blue. And definitely getting dumber by the moment. Jump run direction was changed midflight - either I didn't hear or didn't understand, and I was opening the door. And my exit in the roll up door of the cessna was not a good one, reserve flap came close in contact with the door edge as I peeled out, making the TM inside a bit nervous until I cleared the tail. My mind started clearing up as I passed 15.

USPA sim suggests B license for an 18 and a C for above 20, but that's probably overkill. Greatest concerns to me are the O2 system and spotting issues. Should be outs readily available. Judgement will be impaired at exit time.

[diablopilot 2]

http://skydance.net/sd/highj.htm

http://skydance.net/sd/highalt.txt

One of the most profesional operations I've seen.

----------------------------------------------
You're not as good as you think you are. Seriously.

[chaoskitty 0]

Very good! Thanks!

[kallend 1,623]

Quote

21,000 feet. I'm just looking for some information to fwd to another jumper. Her instructors cleared her to make the jump. Shes very current but also very new. I just wanted to give her some info so she can make a better informed decision, and prepare herself, rather than just trusting its OK for her to do because her instructor said so.

What's wrong with the stuff in the SIM?

...

The only sure way to survive a canopy collision is not to have one.

[chaoskitty 0]

Nothing at all. Just seeing what else is out there.

[MikeForsythe 0]

This is the group that is at Rantoul. Very professional. http://halojumper.com/

Time and pressure will always show you who a person really is!

[chuteless 1]

If you go from an in aircraft console oxygen supply to a bail out bottle, you would be on the bailout bottle while in the door and there would be no impairment . The only difference is the bailout is 2000psi, while the console is a demand regulator.

Bill Cole

[kelpdiver 2]

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If you go from an in aircraft console oxygen supply to a bail out bottle, you would be on the bailout bottle while in the door and there would be no impairment . The only difference is the bailout is 2000psi, while the console is a demand regulator.

Bill Cole

Bill - this outfit did not use a bailout bottle for the 24k jump. Others do, like Skydance. $500 versus 50. So I kept my mask until the group in front of me exited, did my 12 count, and went out.

Does anyone uses a bailout for a 21k exit?

[billvon 2,400]

>Does anyone uses a bailout for a 21k exit?

Heck, we didn't use bailouts for 26K exits.

I have, however, been wondering about how to do that. I recently purchased the smallest refillable oxygen bottle/regulator assembly known to man, and it was still pretty bulky. If you could find a way to store half a liter of oxygen in a low pressure bladder (a bean can sized balloon, for example) and dribble it out over the first 30 seconds of freefall from high altitudes, it would go a long way towards solving a great many problems with high altitude skydives.

[monkycndo 0]

Just did a 24K jump this weekend. I don't smoke and didn't drink the night before. We were on O2 at 2K and kept it on till 24K except to adjust my helmet. Some people were effected. Our prejump instructions were to keep the mask on the whole way up and keep our body movements to a minimum. I dropped the mask just as I went through the door. I followed the advice and never felt any symptoms of hypoxia.

50 donations so far. Give it a try.

You know you want to spank it
Jump an Infinity

[kelpdiver 2]

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Heck, we didn't use bailouts for 26K exits.

So what was done to mitigate the risk of decompression illness? The scant material I could find suggested that 25k was the threshhold where jumpers not on constant true 100% O2 could get into trouble. A slower ascent rate or supplemental O2 alters the point, whatever it may be. But all the good available science focuses on water, not air.

with the large group exits (presumably?) you were doing, did everyone just drop their mask/hose on Ready!?

[kelpdiver 2]

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J Some people were effected.

hah - I bet your lips were drooling just like everyone else! Everyone is affected on that run.

I wish they wouldn't do that load at 7 in the morning - lack of sleep is a factor along with hydration and motion.

[LouDiamond 1]

I have had this discussion several times before and despite what goes on in the civilian skydiving world, you cannot fool with physiology, you are simply rolling the dice each time you do it incorrectly. A good article that covers a lot of the questions people have can be found HERE
Scroll down to the portion titled "How does altitude affect your body" if you are not up to the physics behind this subject. It amazes me how lightly people take this subject simply because they have done a high altitude jump before. But as they say..."ignorance is bliss.."


Be sure to read the effects at different altitudes and what effects rapid ascent(king air ride) can have on your body.


Another article with more information on DCS can be found HERE
be sure to read the part about 100% O2 and the "Predisposing factors" and don't forget about Murphy when considering the info in that article.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[LouDiamond 1]

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I recently purchased the smallest refillable oxygen bottle/regulator assembly known to man, and it was still pretty bulky

Is THIS what you are refering to? The 36 is pretty small(coke can size)

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[kelpdiver 2]

You wrote the same thing in the wingsuit section, didn't respond to either of my posts in reponse. That was with regards to a 20k jump...21k is effectively same in this.

"This article seems focused on the risks to high altitude decompression in a pressurized aircraft. It still points to 25k as the threat altitude, even in the pressurized vessel. This is rather different from an open air craft where people are breathing at least enriched oxygen. Bolting to the surface from 100ft will cause bubbles, or microbubbles to form. A slow ascent on nitrox is far more gentle to the body.

I'm not seeing the risk at 20, at least not from nitrogen. Skymonkey - did they test Ron for a PFO? A lot of unexpected DCS cases are attributed to that common heart defect. I was a bit concerned about the higher 23-24 runs without prebreathing, but I've not been able to find much more than 'DCS cases have occurred.' Meanwhile several operations do it without for 40-50$, and Davis does 24k with for $500. ($600 for the 30k load) "

Prior to that, I wrote:

"At 20k, nitrogen really isn't an issue, is it? 25k is the threshhold where decompression sickness becomes a concern, with more susceptible people being at risk a tad lower. At 20, you just need excess oxygen (and hopefully a quick climbing plane) to avoid a big hypoxia deficit.

Do you know many cases of skydiver DCS? What sort of hits are they taking - the scratchy skin or joint pain of a type 1...any type II hits to the CNS?
(going to search on you and high altitude now)"

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I'm open to hearing more on the subject, but so far I think you're overstating the risks substantially wrt decompression concerns.

[LouDiamond 1]

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I think you're overstating the risks substantially wrt decompression concerns.

I am merely trying to show what the possible outcomes are and educate those who have no accurate idea what is involved. The incident of DCS may be small but it is still a possibility. Throw in the uncertainty of lack of sleep, fluids, and excess alcohol/drug intake associated with most boogies, where these types of jumps usually occur, and the numbers you see in those reports will no doubt be lowered substantialy and vary from person to person. Having seen guys fall out on the floor at "normal" skydiving altitudes and others have altitude related health problems after having gone through an extensive physical and chamber ride I don't kid myself about the realities of flying at altitudes even as low as 12.5. Denying or playing down the Physiology of high altitude exposure is like saying gravity isn't really constant.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING

[billvon 2,400]

>So what was done to mitigate the risk of decompression illness?

Fairly high flow rates starting at 12K; that's about it. We had no problems with decompression illness but a few problems with hypoxia.

>with the large group exits (presumably?) you were doing, did\
>everyone just drop their mask/hose on Ready!?

For the most part. On the arizona record I stayed on O2 until the base exited (I was a late diver) and on the thailand record I was on until about 5 secs before exit.

[chuteless 1]

I think such a proposition as you describe is totally irresponsible.

Either use proper equipment or stay on the ground.

The bailout bottles of the military are about 2 inches in diameter and 12 inches long, they are under 2000 psi and will get you down to opening altitude without any problem. They weight about 1 pound. That is hardly an inconvenience.

I have done 22K + without a bailout bottle, and on one jump we shared a walkaround botrtle to altitude.

Over 30 K pre breathing IS necessary and a console in the plane and a bailout bottle.

"A balloon bladder...allow it to dribbkle out ( while freefalling at 150 MPH) what nonsense.

Do this and you will have a death or two to investigate.....and serve as a terrible wakeup call

Bill Cole

[billvon 2,400]

>Do this and you will have a death or two to investigate.....and
>serve as a terrible wakeup call

Since we _don't_ do this now and haven't had many problems, I can't see how adding more oxygen to the equation is going to hurt.

[kelpdiver 2]

so again, let's talk specifics, not what happens in a unplanned decompression of a passenger plane at 35k.

How many skydiver DCS (not hypoxia) cases are you familiar with in the 20-24k range, and what type (I or II) was it?

There is absolutely no DCS risk at 12.5. Hypoxia, sure. Let's keep the two issues clearly separate.

[LouDiamond 1]

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How many skydiver DCS (not hypoxia) cases are you familiar with in the 20-24k range, and what type (I or II) was it?

I know of 4 cases, not sure of the type on 2 of the cases. I witnessed 2 of those cases where we had to actually come down and take the dudes to the hospital.It was not pretty.

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There is absolutely no DCS risk at 12.5. Hypoxia, sure. Let's keep the two issues clearly separate.

I will agree however, both Hypoxia and DCS are the results of being at a higher altitude. One is obviously more serious then the other, both are to be taken seriously. I will refer you back to our previous conversation on this where chuck gave an example of a jumper who suffered from DCS and didn't go over 13,000. The point of all of this being not to scare people but to educate. When it comes to physiology and high altitude jumping you only have 2 ways, the right way and the wrong way. You can get away doing it the wrong way for a while but the house will eventually win one day. I won't argue about physiology just like I won't argue about gravity. I do however think people should know what the inherent risks are, even the ones that have a low incident of happening.

"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING