Reserve characteristics?

[mattjw916 2]

Quote

That's funny because I can't remember anyone ever dying after a Cypres fire years ago.
This phenomenon started about 6 -7 years ago from the best that I can conclude.

Well, I guess I'm sorta safe then since I built my current rig in 2006.

All kidding aside; I'm not trying to be argumentative or anything but the sample size for skydiving fatalities, especially when you narrow them down to a specific type, is fairly small (which is good obviously). Sometimes shit just happens... call it "the rule of threes", a coincidence, or just Bill Booth's aphorism that "the better gear gets, the more ways skydivers will find to kill themselves in it" just manifesting itself.

I don't know, maybe the next generation will be making fun of us with our "black death" reserves and such... whatever happened with the pierced bridle issue while we're at it? Was that really a widespread problem? I literally don't hear a soul mention it in the "real world". Will this end up the same way? Time will tell I guess.

Cheers

NSCR-2376, SCR-15080

[lyosha 46]

mattjw916

Reserve size is actually a pretty easy choice for an average sized person. Anything 170ish and larger loaded under 1.2 is quite forgiving. By the time you get enough experience to pick out something smaller you should have learned at least enough to know how big a hole you're digging for yourself if you run into trouble under the sportier options.

There we go, this is very helpful, thank you.

[GLIDEANGLE 1]

mattjw916

... whatever happened with the pierced bridle issue while we're at it? Was that really a widespread problem? I literally don't hear a soul mention it in the "real world".

The TWO friends of mine who had the "pierced bridle PCIT" thought it was a problem.

1. I think that the problem was massively UNDER reported. If I know of two friends who had that happen in my tiny corner of the skydiving world, it seems likely that it happened A LOT more than was ever reported.

2. I think that the manufacturers generally have done a terrible job of responding to it. I know of at least one manufacturer who "approved" the bottom-up main bridle routing.... but didn't bother to announce it. WTF was the thinking behind that?

The choices we make have consequences, for us & for others!

[virgin-burner 1]

voilsb

***My guess is that unless there's someone out there who either test jumps different reserves or really enjoys demoing reserves, this isn't an easy question to answer.

I plan to do something like this in the spring. Demo a handful of resesrves (PD, OP, maybe Nano or Smart) and put a bunch of jumps on them, keep detailed notes, and write up an article for DZ/Parachutist/BlueSkies talking about how they pack, open, fly, and land. I can't perfectly duplicate a reserve opening, but I can free pack it like a reserve or base canopy to simulate it.

have you done this? can you supply a link?

and yes, holy thread resurrection..

“Some may never live, but the crazy never die.”
-Hunter S. Thompson
"No. Try not. Do... or do not. There is no try."
-Yoda

[hackish 8]

GLIDEANGLE

2. I think that the manufacturers generally have done a terrible job of responding to it. I know of at least one manufacturer who "approved" the bottom-up main bridle routing.... but didn't bother to announce it. WTF was the thinking behind that?

Keep in mind that out of tens of millions of jumps the issue has happened a few times. UPT did testing and added it as an alternative method to their manual. Skydivers do read the manuals right?

I think the worst thing they could have done would be to just tell people to switch from a method that has millions of successful tests to one that has hundreds. What if that introduced a different unforseen problem that occurred once in every 10,000 jumps not one in every 10,000,000 would we be better off?

-Michael

[mxk 1]

hackish

***
2. I think that the manufacturers generally have done a terrible job of responding to it. I know of at least one manufacturer who "approved" the bottom-up main bridle routing.... but didn't bother to announce it. WTF was the thinking behind that?

Keep in mind that out of tens of millions of jumps the issue has happened a few times. UPT did testing and added it as an alternative method to their manual. Skydivers do read the manuals right?

It's now the primary method in the updated manual. I really wish they had a mailing list to let people know when new documents are published... It also looks like new Vectors will no longer have the hook velcro on the top main flap. I had to request this explicitly when ordering my V3 a few months ago.

hackish

I think the worst thing they could have done would be to just tell people to switch from a method that has millions of successful tests to one that has hundreds. What if that introduced a different unforseen problem that occurred once in every 10,000 jumps not one in every 10,000,000 would we be better off?

-Michael

One of the instructors at DeWolf's course actually pointed out to me that routing the bridle from the bottom may cause problems if you happen to deploy from an upright position. You have to leave enough slack to allow the pin to rotate 180 degrees.

[riggerrob 558]

... It also looks like new Vectors will no longer have the hook velcro on the top main flap. I had to request this explicitly when ordering my V3 a few months ....

One of the instructors at DeWolf's course actually pointed out to me that routing the bridle from the bottom may cause problems if you happen to deploy from an upright position. You have to leave enough slack to allow the pin to rotate 180 degrees.

............................................................................................

All curved pins need some slack ... Roughly double the length of the pin ... That is why many rigs have a small piece if Velcro on the top flap, to remind packers to leave a bit if slack in the bridle before it disappears inside the container.

[virgin-burner 1]

riggerrob

... It also looks like new Vectors will no longer have the hook velcro on the top main flap. I had to request this explicitly when ordering my V3 a few months ....

One of the instructors at DeWolf's course actually pointed out to me that routing the bridle from the bottom may cause problems if you happen to deploy from an upright position. You have to leave enough slack to allow the pin to rotate 180 degrees.

............................................................................................

All curved pins need some slack ... Roughly double the length of the pin ... That is why many rigs have a small piece if Velcro on the top flap, to remind packers to leave a bit if slack in the bridle before it disappears inside the container.

uhm, excuse my ignorance, i think that's the first time i've heard that? if i've let double the length of the bridle hang out on my vector it would only be a matter of time until it snagged on something and i'd be hanging on the tail of the plane and/or had a premie in freefall. that is with the from bottom to top method of routing the bridle.

“Some may never live, but the crazy never die.”
-Hunter S. Thompson
"No. Try not. Do... or do not. There is no try."
-Yoda

[skydiverek 55]

riggerrob

All curved pins need some slack ... Roughly double the length of the pin ... That is why many rigs have a small piece if Velcro on the top flap, to remind packers to leave a bit if slack in the bridle before it disappears inside the container.

Riggerrob: they are talking about the NEW method (attached), not the old method.

[skytribe 16]

hackish

***
2. I think that the manufacturers generally have done a terrible job of responding to it. I know of at least one manufacturer who "approved" the bottom-up main bridle routing.... but didn't bother to announce it. WTF was the thinking behind that?

Keep in mind that out of tens of millions of jumps the issue has happened a few times. UPT did testing and added it as an alternative method to their manual. Skydivers do read the manuals right?

I think the worst thing they could have done would be to just tell people to switch from a method that has millions of successful tests to one that has hundreds. What if that introduced a different unforseen problem that occurred once in every 10,000 jumps not one in every 10,000,000 would we be better off?


Completely agree with a hackish that the manufacturers have responded correctly. I've heard the remark well crw jumpers have been routing this way for years so must be OK but this was from someone that obviously didn't fully understand the reason why the CRW bridle routing was different. And really you want to change the packing process based upon what CRW jumpers do. Have you seen some of there pack jobs.

The new routing will almost certainly work but lets look at reality and how many jumps have been made on all the rigs using the old routing against occurences of bridle piercing.

What has changed that these events only appeared to start occurring in the last few years ? I can't believe this has been happening for years and we have chosen to ignore it. It is just that the internet just give a small minority a loud voice to make this appear a bigger problem than it actually is ? Is it more specific to new disciplines such as wingsuits with different pull angles ? A number of questions need to be answered before I would advocate everyone changing there routing ?

[gowlerk 1,912]

Quote

What has changed that these events only appeared to start occurring in the last few years ?

What has changed is that bridles are now made of Type 3 tape instead of thicker type 4 square weave. This is done because 2 layers are needed to allow for the kill line. At first one layer of each was used, now most makers use 2 layers of type 3 in order to decrease the bulk.

I'm not sure how this ended up in a thread about reserve characteristics! Major drift going on.

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[skytribe 16]

So there you go - if its that simple then manufacturers could simply change back to original configuration. Its not as though this hasn't happened in the past when manufacturers have done something and then backtracked - remember soft housings.....

I think the little bit of slack is the important thing and this was explained to me a long while back - hence the Velcro square on flap 1. Jumpers would introduce the slack by mating the Velcro.

[Hellis 0]

virgin-burner

***... It also looks like new Vectors will no longer have the hook velcro on the top main flap. I had to request this explicitly when ordering my V3 a few months ....

One of the instructors at DeWolf's course actually pointed out to me that routing the bridle from the bottom may cause problems if you happen to deploy from an upright position. You have to leave enough slack to allow the pin to rotate 180 degrees.

............................................................................................

All curved pins need some slack ... Roughly double the length of the pin ... That is why many rigs have a small piece if Velcro on the top flap, to remind packers to leave a bit if slack in the bridle before it disappears inside the container.

uhm, excuse my ignorance, i think that's the first time i've heard that? if i've let double the length of the bridle hang out on my vector it would only be a matter of time until it snagged on something and i'd be hanging on the tail of the plane and/or had a premie in freefall. that is with the from bottom to top method of routing the bridle.


You don't have to have the bridle hanging outside the rig, just not let the bridle have 'tension'.
If you don't have the slack, and have a tight rig and tight closing loop and tight container flaps and in the 'correct (incorrect) position' when you pull the pilotchute will pull on your flaps and the pin won't move.

There is a few topics on pin-locks on watch the bridle http://www.watchthybridle.com/2013/10/pin-locks-in-detail/ and http://www.watchthybridle.com/2013/10/pinlocks/ and http://www.watchthybridle.com/2014/02/pin-orientation/

[pchapman 261]

Hellis

There is a few topics on pin-locks on watch the bridle http://www.watchthybridle.com/2013/10/pin-locks-in-detail/ and http://www.watchthybridle.com/2013/10/pinlocks/ and http://www.watchthybridle.com/2014/02/pin-orientation/

He has good stuff but with the caveat (for those who haven't clicked through) that it is BASE oriented so that concerns may be different. One can pack for skydiving and not give a damn, in ways that would not be optimal for low altitude freefall BASE.

Still, his work gets people thinking about the mechanisms of how pins pull.

[skytribe 16]

Quote

You don't have to have the bridle hanging outside the rig, just not let the bridle have 'tension'.
If you don't have the slack, and have a tight rig and tight closing loop and tight container flaps and in the 'correct (incorrect) position' when you pull the pilotchute will pull on your flaps and the pin won't move.

This slack or lack of tension on the bridle in the original routing was under the pin protector flap. Out of the way and protected from the wind. The Velcro square sort of meant if you mated the velcro parts up the bridle wouldn't be under tension. Without this small bit of velcro and people wanting to tuck any excess bridle away. They may have tucked the excess bridle under the flap to keep things neat and therefore put but the bridle under tension and as a result we started to see incidents. This coupled with the different angles the pin is being pulled for wingsuit deployments may have lead to increased occurrence. Albeit still a relatively small number in the overall scale of things.

My gut feeling is probably materials are probably not the major cause of bridle piercing but more how we are stowing the excess and understanding why the bridle should have hat little bit of slack (Not under tension).

[shadeland 5]

On 1/15/2014 at 2:45 PM, masterrigger1 said:

 

The TSO requirements have been changed to allow canopies to snivel or have longer deployments. These same reserves, although they may have met the TSO requirements, may not actually meet the TSO requirements of another older TSO like in some of the H/Cs still have.

 

Hi MEL, 

I know this is a very old thread, but I was curious about this doing research for Optimums so I did some digging. 

All of the PD Optimums are authorized under TSO c23d. The testing standards is of course SAE 8015b, which states opening should take no more than 300 seconds or 3 seconds. It's also the same TSO that the Aerodyne Smart reserves (regular and LPV) as well as Icarus World reserves (regular and nano). 

The PD Reserves are certified under c23b, c23c, or c23d, depending on when they're made I believe. 

c23f: Covered in PIA 135v1.4, section 4.3.8. It's an equation that takes maximum opening weight and maximum opening speed as inputs. The PD Optimums and PD Reserve aren't covered by this. Plugging in the various vendor weights and speeds, they're mostly in line with c23d. 

c23d: Covered in SAE 8015 rev b, section 4.3.6: Max 3 seconds or 300 feet. Exception is for over 250 lb, it can take a little longer (.01 seconds per pound). 

c23c: Covered in SAE 8015 rev a, section 4.3.6: Specifies only 3 seconds fully open from pack release.

c23b: Covered in NAS 804, second 4.3.4: Open within four seconds.

So from what I can tell, the optimums are required to open in the same amount of time as two of the other major vendors (Aerodyne and Icarus), and it's pretty much in line with the older TSOs as well. 

 

 

Edited June 18, 2023 by shadeland

[JerryBaumchen 1,048]

10 hours ago, shadeland said:

Hi MEL, 

I know this is a very old thread, but I was curious about this doing research for Optimums so I did some digging. 

All of the PD Optimums are authorized under TSO c23d. The testing standards is of course SAE 8015b, which states opening should take no more than 300 seconds or 3 seconds. It's also the same TSO that the Aerodyne Smart reserves (regular and LPV) as well as Icarus World reserves (regular and nano). 

The PD Reserves are certified under c23b, c23c, or c23d, depending on when they're made I believe. 

c23f: Covered in PIA 135v1.4, section 4.3.8. It's an equation that takes maximum opening weight and maximum opening speed as inputs. The PD Optimums and PD Reserve aren't covered by this. Plugging in the various vendor weights and speeds, they're mostly in line with c23d. 

c23d: Covered in SAE 8015 rev b, section 4.3.6: Max 3 seconds or 300 feet. Exception is for over 250 lb, it can take a little longer (.01 seconds per pound). 

c23c: Covered in SAE 8015 rev a, section 4.3.6: Specifies only 3 seconds fully open from pack release.

c23b: Covered in NAS 804, second 4.3.4: Open within four seconds.

So from what I can tell, the optimums are required to open in the same amount of time as two of the other major vendors (Aerodyne and Icarus), and it's pretty much in line with the older TSOs as well. 

 

 

Hi shade,

Without going thru a bunch of old documents [ some, I no longer have ], I believe that the 300 ft req'ment is an optional test; yes/no?

Jerry Baumchen

PS)  Re:  c23b: Covered in NAS 804, second 4.3.4: Open within four seconds.

That is a Twisted Lines test, not a Functional test.

 

TSO C23b NAS 804.pdf

[shadeland 5]

2 hours ago, JerryBaumchen said:

Hi shade,

Without going thru a bunch of old documents [ some, I no longer have ], I believe that the 300 ft req'ment is an optional test; yes/no?

Jerry Baumchen

PS)  Re:  c23b: Covered in NAS 804, second 4.3.4: Open within four seconds.

That is a Twisted Lines test, not a Functional test.

 

TSO C23b NAS 804.pdf 1.25 MB · 0 downloads

Ah yup, my mistake. 4.3.3 is the open pack, normal. 3 seconds. 

I found this older copy of the FAA parachute rigger handbook (from 2005) which has all the standards that had been used up until then (8015a/b, NAE). 

Parachute-Rigger-Handbook.pdf

[shadeland 5]

The PD Reserve is c23b or c, I think depending on when it was made (3 seconds). The PD Optimum as well as the Aerodyne and Icarus reservers are c23d (3 seconds or 300 feet). 

c23f uses an equation, and I took the weights and speeds listed in the PD Reserve and PD Optimum and made some graphs on what the allowed altitude loss and opening time were if they were tested to c23f (which they're not). So the c23f is not too far off from c23d. (Keep in mind anything under 3 seconds or 300 feet would allowed to just be 3 seconds or 300 feet with c23f, so even though the smaller ones are less than 300/3, the standard specifies "or"). 

[riggerrob 558]

The generation of Technical Standard Order will not change with the date of manufacture. The TSO will only change after the manufacturer repeats all those drop tests and receives approval from the FAA. Given that drop tests cost something like $1,000. per jump, few manufacturers are going to repeat drop tests just to get an updated TSO. They are allowed to continue manufacturing - under the original TSO - as long as they keep the accident rate low.

The FAA is unlikely to insist on any changes considering how few skydivers die every year. Skydiving will remain a low priority for the FAA as long as we keep fatality rates low.

[riggerrob 558]

Returning to the original question ... if you want to experience how a reserve turns and flares, borrow a ZP 7 cell the same size, say a Triathlon. The Triathlon will not open as hard/quick, but it will turn and flare similar to a new reserve of the same size.