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sukaidaiba

Balloon altitude

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Within 5 seconds from exit the jumper will be doing 85 mph, which is about the same airspeed as an Otter exit, and with a loss of altitude of only 370 feet. So they'll be at 2,630 feet AGL with plenty of airspeed to get stable for deployment. Since minimum opening altitude is 2,000', this should be sufficient for most jumpers.

For this particular person with 100 jumps and used to opening at 3,000', it's a personal judgement call.



Min opening per BSR is certainly higher - 2500ft for a B. And since this is likely an off landing, it seems prudent not to go to the minimum anyway. On the otter my canopy should be fully open and flying by 2700.

I'm going to do a helicoptor one first. I have a better guarantee of altitude and can have a good LZ below me.

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The problem with a balloon jump is that you'll often have to land off. The altitude and still air shouldn't present a problem, unless you flail so hard you knock yourself out. :D

Most places require a B-license (50 jumps), I think, but I waited until I felt comfortable enough that landing off wouldn't scare the living shit out of me (app. 200 jumps). And the people in my group landed in some very small, tree-and-powerline lined areas. I probably wouldn't have been comfortable with that at 50 jumps.

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I did my first baloon jump at about 100 jumps.

I packed my main with my slider 1/2 way down and deployed immediately.

I exited at 2500ft with my cypress off.

everything went well...amazingly.. the opening was one of the best I ever had. I was open around 1700ft according to my log book.

I had to land in a 500ft by 50ft grass area with power lines on either side.



I survived, but when I look back im surprised I didnt get hurt.


If you do decide to do it with 100 jumps, make sure you bring along a friend who you trust and is experianced who can guide you though the entire thing..packing, making sure your cypress is off, spotting, etc.

Also, make sure the baloon guy knows you need to go to 4,000 feet and tell the damn baloon guy to fu*k off if he tells you to get out at an altitude below where you are confortable at....I paid to go to 3k, but was told to get out at 2.5. Decide your altitude before hand and stick to your plan.

Go as high as he will take you...no sense in getting out lower if you dont have to or if you dont feel confortable with it.

Also, make sure there are arrangements to get bacdk to t the dz. I had to hitchhike back.

:)

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Please explain why the balloon would be in descent.

Although I never jumped from a balloon, I have gone for a balloon ride two times as a pure passenger. I think it's because once they turn off the burners, and all the time you spend climbing out to position yourself properly, the balloon is now already back into descent. They are not going to re-activate the burners while you're climbing out and before you jump. If you rushed the climbout, it's possible the balloon will still be ascending, but I don't think the pro's would recommend that.

Someone else will definitely provide a better answer, but I always notice the balloon doesn't take too long after the burner is off, before it's back into a descent.

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Don't forget that the balloon will be in a descent itself when you exit. You will be losing altitude.



Please explain why the balloon would be in descent.



Perhaps it is because they don't like to have sudden airspeed, it might deform the envelope. So if they are descending when you go, then the transition to upward airspeed means less maximum airspeed. Actually, I don't believe this at all but a balloon pilot I talked to said that the sudden loss of weight causes a lot of stress. Seems like it would not be very severe compared to some ascent/descent rates I have observed.
People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

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plenty of height



No it isn't. 3000' is adequate but not plenty. A hop and pop from a balloon has quite different dynamics than a hop and pop from a plane due to the absense of any initial airspeed. For someone with 101 jumps, accustomed to deploying at 3,000ft, I'd not recommend 3,000 ft for a first balloon exit.



Within 5 seconds from exit the jumper will be doing 85 mph, which is about the same airspeed as an Otter exit, and with a loss of altitude of only 370 feet. So they'll be at 2,630 feet AGL with plenty of airspeed to get stable for deployment. Since minimum opening altitude is 2,000', this should be sufficient for most jumpers.

For this particular person with 100 jumps and used to opening at 3,000', it's a personal judgement call.



He lists 101 jumps, and states he has a "B" license. Per the BSRs


G. Minimum opening altitudes


Minimum container opening altitudes above the ground for skydivers are:


1. Tandem jumps--4,500 feet AGL

2. All students and A-license holders--3,000 feet AGL

3. B-license holders--2,500 feet AGL

4. C- and D-license holders--2,000 feet AGL



I stand by what I wrote.
...

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

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my first and only balloon was from 6.5K at 105 jumps. The delay seemed like forever before a pull at 4K. We did some informal CrEW (no contact) - then landed in a huge field we preplanned.

I would not do a 3K balloon, but I would do a 4K balloon.

Just my opinion....

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Don't forget that the balloon will be in a descent itself when you exit. You will be losing altitude.



Please explain why the balloon would be in descent.


First of all a ballon is virtually always in a slight descent unless you have just heated it.

When your weight leaves the balloon it suddenly has a lot more buoyancy. It will suddenly rise up causing the balloon's evelope to distort significantly. This can be catastrophic if multiple jumpers left at the same time and the balloon had just been heated.

Most balloon pilots will put the balloon into a rapid (even terminal) descent prior to letting jumpers exit. Once the jumpers exit, then the balloon stabilizes and either continues a slight descent or ascends slightly. The key is to avoid a rapid ascent that can cause problems.

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>Perhaps it is because they don't like to have sudden airspeed, it might
>deform the envelope. So if they are descending when you go, then the
>transition to upward airspeed means less maximum airspeed. Actually, I
> don't believe this at all but a balloon pilot I talked to said that the
> sudden loss of weight causes a lot of stress.

At Eloy they exited something large from a balloon (8-way?) The balloon was in a descent before exit, but even so, after exit the envelope was hideously deformed; it was almost on its side at one point. They're not designed to withstand much airspeed.

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Hi I've been offered a balloon jump of agl between 3000ft and 5000ft.

I was a little concerned about exiting at the lower end as getting out at 3000ft is my normal pull altitude! Is this normal, to people just hop and pop?



Taking a four second delay from a baloon will have you opening with the same time to impact as when you pull at 3000 feet on a terminal skydive. Your opening will happen at 2750 feet so you'll still have lots of altitude for your emergency procedures.

Opening immediately at 3000 feet wouldn't be much fun.

You might pull following a very unstable exit if you won't open lower You don't have any air to work with for about 3 seconds and even then its real mushy so you won't be able to do much aerodynamically to correct any problems.

OTOH a skydiving pilot chute won't have much drag at that speed.

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Perhaps it is because they don't like to have sudden airspeed, it might deform the envelope. So if they are descending when you go, then the transition to upward airspeed means less maximum airspeed. Actually, I don't believe this at all but a balloon pilot I talked to said that the sudden loss of weight causes a lot of stress.



Think of the balloon and lines as being a rubber band stretched out tight by the weight of the jumpers in the basket. After all, the balloon is trying to ascend, while at the same time the weight in the basket is holding it back, so these two forces are opposing each other and creating a lot of tension. When the weight is suddenly released, the balloon shoots upward, and the envelope can be deformed in some scary ways to the poor pilot who remains behind in the basket, probably cowering in the bottom and hanging on for dear life. So a smart balloon pilot who knows about dropping jumpers will put the balloon into a mild descent before jumper exit, to mitigate this rebound reaction.

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I stand by what I wrote.



I didn't say anything to the contrary. I just pointed out in explicit numbers that the hypothetical jump can be done safely and within the guidelines of the BSR's, although admittedly it is close.

The only difference between us is that you recommended he not do it, and I said it would be a personal judgement call. There isn't much difference between those two positions.

I know you're so used to disagreeing with me in Speaker's Corner, that sometimes it's just automatic...

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I jumped from balloon 4 times in Eloy and all times it was climbing as jumpers were exiting. Typically, they would start at 5K and by the time 4-5 jumpers are gone the baloon rises to 5.5K. I know because I jumped last :)




try 7k B|... but burner still does put the balloon in a slight decent before the first group exits... it the groups are large enough he will do it again before the next..
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I jumped from balloon 4 times in Eloy and all times it was climbing as jumpers were exiting. Typically, they would start at 5K and by the time 4-5 jumpers are gone the baloon rises to 5.5K. I know because I jumped last :)



Is it:

A) The balloon is in a decent, but as soon as the weight left the balloon went up a bit

or

B) The balloon is climbing the whole time.

I bet A... I jumped from a balloon in a two-way. We were going down as we left, but the Pilot said he still shot up quite a bit... The danger being that the upward movement can actually compress the air out of the balloon, thus it is better to not shoot up....

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Without the Balloon being in a decent the basket can ricochet into the envelope when the jumper leaves . . . Not good.

As for jumping at three thousand feet keep in mind your starting downward airspeed is zero. It's not like passing through 3000-feet at terminal velocity. I understand your reluctance, since we raised the student jump altitudes (my generation made first jumps from 2800-feet) we sort of made people too afraid of these lower altitudes. I found that out during several emergency exits when even at 2000-feet so called experienced jumpers by the door are confused and balking . . .

I did an emergency exit from a Balloon at 1700-feet (with skydiving, not BASE gear) after the pilot over-temped the envelope and blew out the top. Another jumper with us refused to jump and almost killed himself when he suddenly later realized he was going to die if he stayed. I've also done many Balloon jumps from 600-feet with BASE gear. I think it's important for skydivers to experience minimum altitude exits as in a career, sooner or later, it'll happen to you.

I see DZs where AFF students make their hop & pop from 5000-feet or even higher. What's that about? After all the underlying reason for the hop & pop is an emergency exit situation. It's because their Instructors, now that several generations have passed, have never gotten out low themselves. That's dangerous thinking. Keep in mind if it all really goes to hell, it's always better to jump and try, than stay and fry . . .

Oh, and the fellow who said he put his slider half way up (or down) is giving bad advice. Generally what happens is during line stretch there's a good chance the slider will be "blown" back up the lines. And if it doesn't and you have a stability or gear problem that delays your deployment you're asking for trouble. Even BASE jumpers using BASE canopies, which are very overbuilt, won’t delay more that 3-seconds with the slider disabled. The "best" opening he ever had stems only from the fact he was going so slow . . .

NickD :)BASE 194

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