Opening altitude?

[Clownburner 0]

My DZ recommends informing manifest for any opening above 3000 ft, and I do this; I also make sure everyone on the load around me knows where I'm pulling (I usually pull around 3500).

I've noticed that my openings are pretty slow - nice and gentle and all that, but if I pull at 3500 I'm not in the saddle until 2300 and I feel that's low for my experience level (if anything goes even a tiny bit wrong I'm below my hard deck). If I pull at 4000 I'm in the saddle at 2800 or so. (according to my digitude, it's 1200 feet from grab-and-throw to fully deployed and collapsing slider/unstowing brakes)

So, is manifest talking about how high you're STARTING deployment, or how high when you FINISH deployment??

I presume it's starting deployment, but I've managed to confuse myself (again). Thanks in advance.

7CP#1 | BTR#2 | Payaso en fuego Rodriguez
"I want hot chicks in my boobies!"- McBeth

[billvon 2,465]

>So, is manifest talking about how high you're STARTING deployment,
>or how high when you FINISH deployment??

They care about the altitude you are open BY. That means the altitude you finish deployment by. However, by saying 2500 feet, you are betting someone else's life that you won't have a slammer when you pull at 3500 feet.

I've said this before. A canopy that takes 1200 feet to open is not a very good lifesaving device, no matter how comfy the opening is.

[Clownburner 0]

Quote

I've said this before. A canopy that takes 1200 feet to open is not a very good lifesaving device, no matter how comfy the opening is.

Well, I don't really like that it takes that long to open, but I suppose I have to talk to a rigger or the manufacturer about how to speed it up a little without killing myself in the process. I already use all the tricks I know (which admittedly aren't many) to get it to open as fast as possible - leave the nose hanging, never double-stowing, etc.

But being very new to the sport I really don't know much about how canopies are supposed to open, or how long that typically takes. I know the student Navigators I jumped took at least 1000 feet (1500 feet was not unusual) and managed to bruise me all the time anyway. I've been told they were pretty badly worn out.

7CP#1 | BTR#2 | Payaso en fuego Rodriguez
"I want hot chicks in my boobies!"- McBeth

[councilman24 36]

I have to agree with Bill. 1200 ft to open is questionable performance. Is it really 1200 ft? from the time you release your pilot chute to the time your slider stops moving? Or do you look at your altimiter and think ok it's 3500' time to open, wave off, reach, throw, ride the opening, check the canopy, check for traffic, stow your slider, release the brakes, and THEN check your altimeter. This sequence would really translate into a PACK opening altitude of 3000' and a 500-700 ft canopy opening distance. Just checking your definition of opening distance.

Just reread your post. Collapsing the slider and unstowing the brakes are NOT part of the opening distance normally discussed. At least they're not part of my definition.

As Bill said it's where your canopy is open is what most manifest would care about. Discussions get a little lose between skydivers and usually are Pack opening ("pulling"). "I'm going to open at 3500'. Ok, I'll go to 2500'. And I'm jumping a tandem and pulling at 5000'"

But the difference between pack opening and open canopy vary. My canopies, by my choice take 200-300 ft to open. I consider anything else a streamer that clears itself. So for me to BE open at 2500' I can pull Start reaching at 3000'. My budies with a Spectre my have to start at 3500'.

I'm old for my age.
Terry Urban
D-8631
FAA DPRE

[Clownburner 0]

Good question. here's how it worked on my last jump.

Solo jump out of a Cessna 206, only tandems on the load other than me, no other planes in the air, so the airspace is pretty clear.

Waved off at 4500, looked around and made sure airspace was clear, look at altimeter as I grab the handle (alti shows 4.0), throw out, get vertical, look up at opening, reach for risers, look for traffic. Slider all the way down, check alti: 2.8. Begin collapsing slider/unstowing brakes.

So, it might be a little less than that, if you figure it takes me 3/4 of a second to grab, pull, and throw the pud I'd be actually 'throwing' around 3850 or something like that. I'd like to get video of it so I can verify my facts, maybe I'll do that this weekend. I do know when I first got the canopy and sent it to the factory for inspection / upgrades, they put a larger slider on it free-of-charge, I'm sure that is a factor, but I have no idea what size was on it before (I sent it off for inspection as soon as I got it used).

Anyway you look at it, I don't like throwing at 3500 because I'm open too low.

Edit: I do always double-check to make sure the pilot chute is cocked, but it's a BIG canopy - maybe I need a larger pilot chute? It's a Triathlon 220 (used, about 130 jumps) with a 27" ZP pilot chute (which is brand new).

7CP#1 | BTR#2 | Payaso en fuego Rodriguez
"I want hot chicks in my boobies!"- McBeth

[kallend 1,672]

Quote

>So, is manifest talking about how high you're STARTING deployment,
>or how high when you FINISH deployment??

They care about the altitude you are open BY. That means the altitude you finish deployment by. However, by saying 2500 feet, you are betting someone else's life that you won't have a slammer when you pull at 3500 feet.

Well, I don't know but it seems to me that the reason to inform the load if you're deploying high is to give a heads-up to those who, for whatever reason, may be close to you at deployment time ('cos they didn't leave adequate exit separation or whatever.)

Now, assuming I'm a jumper in the next group and we break off at 4.5 and I track like a bat out of hell and finish up over the high puller, I surely won't be caring where his canopy is fully open. I will be concerned the moment I see him waving off and reaching for his pilot chute (assuming I hadn't spotted him already). I don't want to be over someone initiating deployment regardless of the length of their snivel.

In other words, I'd like to know where he intends to deploy rather than know where he expects to be open.

And more to the point, if he's solo, in the same discipline and deploying high, I'd hope that he agrees to let my group exit first.


edited to fix markup

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

[billvon 2,465]

>I don't want to be over someone initiating deployment regardless of
>the length of their snivel.

I have been in this very state, and there is a huge difference between the two. If you are over someone who is about to pull, or even who is sniveling, you are traveling at about the same speed they are. For example: I have dumped people's reserves, waited until they are stood up, then immediately deployed. Why did I have plenty of separation in this case? Because reserves open faster than my snively main. (Snively in my case is 300-400 feet.)

For most jumpers, this means that if you are over someone about to pull, or someone in the midst of a long snivel, the cases are essentially the same - you either get out of the way or you deploy, if you have a fast-opening parachute. If they are already open, your only hope is to get out of the way; you're not going to be able to open in time unless you've got lots of altitude or a Lightning. The problem with the snively main is not that it will cover the distance between you quickly, it is that it may suddenly STOP being a snively main and decide to open in 200 feet this one time. Which is why a canopy that snivels for 1200 feet can be a problem.

[skymick 0]

How long does it take from when u pitch till the canopy is out of the bag? If its a few seconds it could be possible that the kill line in the bridle is too short so the PC never fully inflates.

[tlshealy 0]

James,
I would contact Aerodyne and ask them about your slow openings and ask why they put a larger slider on it. If it really is taking over 1000 feet to open thats a problem and you should find some way to speed it up, like going back to a smaller slider or venting the one you have now. If your doing RW and find your self opening at 2500' what will you do when your sniveling through 1500?
Tad

[andy2 0]

I would like to add that sometimes a smaller slider will actually slow down the openings further! I believe this is called the reefing effect, and has been explained to me by a rigger at my DZ. It's best to either A) experiment with new equipment setups up higher than usual to add a buffer zone, or B) ask the manufacturer's advice.

Just what I've been told by people at my DZ that agrees with my common sense...

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