riggerrob 643
councilman24 37
Of course your definition of hard opening and MY definition of hard opening may be different. I've jumped a Sabre, either 190 or 170 for hmmm, 13 years? They have always opened the way parachutes opened when they were introduced. Now.
If you don't grunt when it opens it's a malfunction that cleared.
Unlike the modern stuff that stands you up and lets you look at it awhile to decide if it's opening or a streamer. The first time I borrowed a canopy that took 700' to open, IF the owner hadn't warned me I would have cut it away.
Now the market has shifted and the new standard paradigm is to take at least 500' and more like 700' to 800' to open. It's a good thing newer jumpers are moving away from the USPA minimum pack opening altitudes. 2000' for D, decision altitude by 1800' and action by 1600'. Now you know how fast they used to open.
Of course I'm an inch shorter than I was 20 years ago. But the spine guy I went to last year for something unrelated said it look very good for someone with as many jumps has I have.
Anyway, the definition of hard opening has changed. It now incompasses what used to be a normal opening. And normal openings are malfunctions that clear.
Not so good when your using USPA minimum PACK OPENING altitudes and getting out at 2000'
My sabre has spanked me with what I even consider a hard opening from time to time. So take the advice above.
If you don't grunt when it opens it's a malfunction that cleared.
Unlike the modern stuff that stands you up and lets you look at it awhile to decide if it's opening or a streamer. The first time I borrowed a canopy that took 700' to open, IF the owner hadn't warned me I would have cut it away.
Now the market has shifted and the new standard paradigm is to take at least 500' and more like 700' to 800' to open. It's a good thing newer jumpers are moving away from the USPA minimum pack opening altitudes. 2000' for D, decision altitude by 1800' and action by 1600'. Now you know how fast they used to open.
Of course I'm an inch shorter than I was 20 years ago. But the spine guy I went to last year for something unrelated said it look very good for someone with as many jumps has I have.
Anyway, the definition of hard opening has changed. It now incompasses what used to be a normal opening. And normal openings are malfunctions that clear.
Not so good when your using USPA minimum PACK OPENING altitudes and getting out at 2000'
My sabre has spanked me with what I even consider a hard opening from time to time. So take the advice above.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE
Terry Urban
D-8631
FAA DPRE
What about a tandem drogue on a 68?
Come on let's be realistic here. I don't believe in PCs smaller than a 28" for anything smaller than a 150. Skydiving PCs should range between MIN 28-32/34 MAX depending on the size of the canopy.
Yes a bigger PC will increase the snatch force but that is not what gives hard openings.
The only way slow down a canopy on opening is to reduce the force of the air going into the nose. A PC cannot do that no matter how you look at it.
I think all the points but 5 and 7 Bill made are valid.
Come on let's be realistic here. I don't believe in PCs smaller than a 28" for anything smaller than a 150. Skydiving PCs should range between MIN 28-32/34 MAX depending on the size of the canopy.
Yes a bigger PC will increase the snatch force but that is not what gives hard openings.
The only way slow down a canopy on opening is to reduce the force of the air going into the nose. A PC cannot do that no matter how you look at it.
I think all the points but 5 and 7 Bill made are valid.
Memento Audere Semper
903
903
Stumpy 284
I pack for a guy who freestows his lines and gets fine openings - I have never understood linedump. Now if the canopy is out of the bag before linestretch i can see that making a difference hence its a good idea to have firm locking stows. Why should having the lines free give slammers?
Never try to eat more than you can lift
RMURRAY 1
QuoteTry a 7 inch domed slider.... works great!
we make 'em
MEL
Skyworks Parachute Service
I agree. On my recommendation, my DZO bought one of your dome sliders for his Sabre1 170 and now he can dump at terminal. Before he refused due to repeated hard openings - despite trying all packing tricks we could come up with. Cheaper than buying a new canopy!
rm
riggerrob 643
QuoteI pack for a guy who freestows his lines and gets fine openings - I have never understood linedump. Now if the canopy is out of the bag before linestretch i can see that making a difference hence its a good idea to have firm locking stows. Why should having the lines free give slammers?
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Let's keep our terminology straight.
"Free-stowing" and "d-bag" are two vastly different systems.
"Freestowing" (no d-bag, no diaper no strap, in other words, lines laying loose in the pack tray) fell out of fashion circa 1980 after a couple of guys went in with suspension lines half-hitched around the side flaps of their Wonderhogs or Novas.
Free-stowing can also cause hard openings if it dumps the slider in the pack tray along with the lines. If the slider is not hard up against the bottom of the canopy at line stretch, it will open hard.
I suspect that your buddy is using a d-bag - with a couple of locking stows - but just figure-eights his lines in his pack tray. This is a long way from free-stowing as the locking stows hold the slider near the bottom skin until line stretch. However, free-stowing lines in pack trays only works consistently with a few containers (i.e. Racer).
Stumpy 284
Apologies, yes, thats what he does. (stilletto and teardrop incidentally)
but still, this implies that aside from the locking stows, the other stows are there mainly to keep things neat and tidy? thay play no part in the opening sequence?
(Also thinking about the berger bag thread - some people like mjosparky have hundreds of umps with stowless bags.)
Sorry if i am talking rubbish - just trying to understand.
but still, this implies that aside from the locking stows, the other stows are there mainly to keep things neat and tidy? thay play no part in the opening sequence?
(Also thinking about the berger bag thread - some people like mjosparky have hundreds of umps with stowless bags.)
Sorry if i am talking rubbish - just trying to understand.
Never try to eat more than you can lift
Here are my .02 cents. Add a pocket to your slider. It is a simple mod. Most riggers can hook you up and this solved all the problems with hard openings regarding my daughter's Sabre. This mod worked regardless of how it was packed. According to my daughter --Openings are soooooo soft now it is incredible. On the down side, it takes close to 800 feet to open and so you might want to increase your decision altitude.
However, DO SOMETHING. My daughter suffered a fracture of her C5 vertabrae from one of her hard opening and I'm guessing you don't want to learn the same lesson in the same way.
However, DO SOMETHING. My daughter suffered a fracture of her C5 vertabrae from one of her hard opening and I'm guessing you don't want to learn the same lesson in the same way.
Think of how stupid the average person is and realize that statistically half of them are stupider than that.
billvon 3,070
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>No, the brake lines should be like specs.
Agreed, they should be. I have softened the openings on some of my canopies (including a Sabre 150) by lengthening the brake lines, though.
>No, smaller PCs don't give you softer openings.
Too-large PC's can give you harder openings. PD does not recommend large PC's for their canopies for that reason.
(stumpy says)
>Doesn't the hard opening come from the part after the canopy is out of the bag?
Usually, yes. Line stows that are so poorly held that they don't slow down the bag, though, can contribute to hard openings. Imagine line stows that allow the bag to start to open as soon as the bag is lifted out of the pack tray.
Agreed, they should be. I have softened the openings on some of my canopies (including a Sabre 150) by lengthening the brake lines, though.
>No, smaller PCs don't give you softer openings.
Too-large PC's can give you harder openings. PD does not recommend large PC's for their canopies for that reason.
(stumpy says)
>Doesn't the hard opening come from the part after the canopy is out of the bag?
Usually, yes. Line stows that are so poorly held that they don't slow down the bag, though, can contribute to hard openings. Imagine line stows that allow the bag to start to open as soon as the bag is lifted out of the pack tray.
cabbage 0
Hello,
I've a fair few jumps on an original Sabre 170 loaded at about 1.4 standard slider and good trim. I'm not a rigger and by no stretch of the imagination would I consider myself an expert so don't take this as advice just my observations. I always pack for myself so have tried a few different techniques of packing until I'm nw happy with the consistent openings. I've found the openings I'm happiest with come from packing in accordance with the manual but I pay particular attention to making sure the slider quartered and is biased toward the front. I've also found how tight I roll the tail (not how many rolls more how tight the rolls are) makes a difference more than how I roll the nose. I've had one opening that hurt and I put that down to using different bungys from usual. I was jumping back to back loads and had none of the small microline bungys at hand so used some I normally use on student kit. I didn't dump in a track but on opening my feet swung forward to about head height my chin slammed into my chest and I was a wee bit dazed and sore. I'm not sure, and would welcome comment here but I put it down to the line stows not slowing the deployment sequence and thus allowing line stretch and initial canopy deployment while I was still fully belly to earth. I've never used other bungys again on my rig and I've never had another opening like it. I like the canopy and although I've heard plenty of horror stories I'm happy to stick with it but as with most things in life it's horses for courses.
Regards,
Stay safe,
Cabbage.
I've a fair few jumps on an original Sabre 170 loaded at about 1.4 standard slider and good trim. I'm not a rigger and by no stretch of the imagination would I consider myself an expert so don't take this as advice just my observations. I always pack for myself so have tried a few different techniques of packing until I'm nw happy with the consistent openings. I've found the openings I'm happiest with come from packing in accordance with the manual but I pay particular attention to making sure the slider quartered and is biased toward the front. I've also found how tight I roll the tail (not how many rolls more how tight the rolls are) makes a difference more than how I roll the nose. I've had one opening that hurt and I put that down to using different bungys from usual. I was jumping back to back loads and had none of the small microline bungys at hand so used some I normally use on student kit. I didn't dump in a track but on opening my feet swung forward to about head height my chin slammed into my chest and I was a wee bit dazed and sore. I'm not sure, and would welcome comment here but I put it down to the line stows not slowing the deployment sequence and thus allowing line stretch and initial canopy deployment while I was still fully belly to earth. I've never used other bungys again on my rig and I've never had another opening like it. I like the canopy and although I've heard plenty of horror stories I'm happy to stick with it but as with most things in life it's horses for courses.
Regards,
Stay safe,
Cabbage.
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