Steering Line Snaping on Final Flare

[Sandro29 0]

Hello all,

We had a strange incident that happened at our DZ last weekend. I didn't post in the incidents section because this particular one, I don't think there is anything to learn from it in terms of jumper error.

Here are details.

Jumper is very current...flies a Katana 120 with an approx wing load of about 1.7-1.8 I believe. He had a normal opening....flew araound as he normally would, no drastic spins and turns. Does a front riser 180 turn on final, just as he beging leveling off with his toggles....SNAP...break line snaps clean about 3 inches obove the the little loop in the line where you would stow your toggle through.

His gear was in good condition. I've packed it myself a few times and no wear and tear was visible, and the lines did not show any fuzzy stuff arund them, etc. I'm not sure why type of lines they were....

As far as I know, there isn't alot of pressure on the flare to snap a line. I could understand if there was a hard opening that it could have damaged the lines and created a weakness, but he reports he hadn't had any hard openings.

This jumper is in the hospital now with a broken Femur...could have been MUCH worse.

So my question is, has anyone seen this happen before or has heard of this happening?
What could cause it to snap like that?

I haven't yet seen the line itself, but this weekend we'll be checking to see if there are any signs that the line was cut partially (knife, scissors, sharp object) that may have weakend the line and it went un-noticed, or if the line shows wear marks where it snapped...fuzzy stuff around the area where it snaped.

Any suggestions or comments on this....

Thanks

If at first you don't succeed....then Skydiving is not for you!

[airtwardo 6]

Any suggestions or comments on this....

Quote

Without knowing what caused the line to fail, not much to comment on other than I lost a good friend 10 years ago when the toggle knot came undone mid flare... a day before his wedding.

I pack my own parachute...personal inspection of life saving equipment can be a good thing.

~ If you choke a Smurf, what color does it turn? ~

[stayhigh 2]

last weekend i saw a jumper's toggle coming undone due to NO bartack..

it happened about 2 feet off the ground during final flair.. luckily nothing happend to this guy.

Bernie Sanders for President 2016

[gearless_chris 1]

Quote

last weekend i saw a jumper's toggle coming undone due to NO bartack..

it happened about 2 feet off the ground during final flair.. luckily nothing happend to this guy.

I had that happen to my Nitron uhh... twice, once when I released the brakes, and the other when I turned on to final. I made it a point long ago to learn how to rear riser flare every canopy right off the bat, came in handy.
I also had my P.O.S. Cobalt snap both the brake lines right where the cascades came together, on opening, on seperate jumps, there was no prior damage that I remember seeing, and unlike the first time it broke a line it was a pretty clean break.

"If it wasn't easy stupid people couldn't do it", Duane.

My momma said I could be anything I wanted when I grew up, so I became an a$$hole.

[pwln 0]

I've broken a brake line just above the cats eye just after releasing my brakes. (Synergy 170)

I replaced the lower control lines, then shortly after that I broke a center D line. The way I see it, It was time for a new line set. It was HMA with about 300 jumps. (And yes, I've see the recent other threads on HMA and number of jumps. This was at the start of this year and the end of last year.)

I always do a full check after opening.

[billvon 2,421]

>I had that happen to my Nitron . . .

The Nitron, like the Katana, uses HMA line. HMA will look better for longer (maintain trim, look like it's still got some life left) but then tend to fail more abruptly. It is critical to replace HMA linesets regularly even if they look sort of OK.

(Note that the Nitro uses Dacron instead of HMA for the brake lines only to avoid this problem; Dacron is pretty bulletproof. I don't know if the Nitron or Katana use this trick.)

[AggieDave 6]

What are the rest of the details? Line type? Was it the stock HMA or the older lineset using Vectran? Was a special lineset used from a rigger outside of the factory? How many jumps on the lineset?

Got pictures of the lines? Have you sent the canopy back to PD for evaluation?

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[stayhigh 2]

uhhh,,, even dacron will come undone if there were no bartack or knot..

i typed undone,, not break... and the jumper i was talking about had 0 jumps on the line and it was first jump after changing line set..

Bernie Sanders for President 2016

[pwln 0]

The lower control lines on my Synergy were HMA to start with, now they are Dacron (I Think).
When I ordered the first new set of lower control lines, they sent me something (Dacron, I Think) that was way different then what I had.

I sent the canopy to Precision for a reline and it came back with the Black HMA lines and White (Dacron, I Think) lower control lines. NOTE: The Upper control lines are still HMA.

[gearless_chris 1]

I had to replace the brakelines on my Nitron, Precision said they use 400 lbs. Dacron. It worked fine on my Nitron because of the low toggle pressure. I used the leftover material to replace the first broken lines on my Cobalt, not a good idea, I don't recommend it. I found out the hard way that Dacron will stretch a lot with the increased toggle pressure on the Cobalt, like 3 inches of stretch. I'm glad I arched instead of PLFing, probably would have broken something.

"If it wasn't easy stupid people couldn't do it", Duane.

My momma said I could be anything I wanted when I grew up, so I became an a$$hole.

[DougH 270]

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(Note that the Nitro uses Dacron instead of HMA for the brake lines only to avoid this problem; Dacron is pretty bulletproof. I don't know if the Nitron or Katana use this trick.)

I am thinking about going this way on my Mamba. If I snap a brake line it won't be pretty. The dacron will be pretty stable as far as shrinking goes right?

"The restraining order says you're only allowed to touch me in freefall"
=P

[GLIDEANGLE 1]

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line snaps clean about 3 inches obove the the little loop in the line where you would stow your toggle through.

If the finger trap for the cat eye is made incorrectly there can be a high stress point in the outer line at the point where the inner line ends. This might be approximately at the point that you describe.

In The Parachute Manual Vol 2, Poynter discusses this issue with regard to Spectra (Section 8.8). I suspect that this publication preceeded the use of HMA lines, and thus does not mention it. I suspect that the same principle would affect both Spectra and HMA lines.

If the inner line is not taperd enough and/or is cut with a hot knife the resulting lump or abrupt change in diameter in the inner line can be a problem for the fibers of the outer line.

Hope that the jumper recovers quickly.

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

[BMFin 0]

How many jumps on the lineset ?

Personally I just changed my lower steering lines, though my lines overall seem still fine. The guide ring creates a lot of rubbing in the break locking loop area and to me it just seems that its exactly the part of a line set that wears out quickest..

At the time I yet dont constantly plane out with rears so snapping a toggle during the plane out phase might be pretty messy..

And yeah I agree.. Could have been much worse, than just a femur.

[Sandro29 0]

Thanks everyone for the replies.

I spoke to a number of jumpers around here and nobody seems to be aware of this potential issue/problem. I can tell from the responses that it has happend on a number of occasions. I'm surprised most jumpers (even the experienced ones) don't seem to be aware of this, or at least haven't considered this issue....as part of 'what would I do if it happend to me'

I'm definately going to learn a little more about lines and line types for my own comfort.

Please keep any additional comments comming....i'm learning here.

Regards,
FEZ

If at first you don't succeed....then Skydiving is not for you!

[pwln 0]

Here is a recent thread about 300 lb hma. This may not apply here but is really worth reading.
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=3281115;search_string=hma;#3281115

[Sandro29 0]

Ok, here is a thought...Although I haven't looked at my risers yet, wouldn't it be approx. 3 inches from the cat eye in the steering lines or the point where we stow our brakes, to the connector point on the risers?

I'm wondering if the connector point on the risers (where the risers attach to the lines) can cause a weakness on the steering lines, even though many of us use Slinks as opposed the hard links?

I'm going to open my gear tonight and look over that area just for curiosity. I'm thinking that just the fact that it sits in your container, the brake line may be constantly pushing or resting against that point, which could cause a weakness over time....

Thoughts anyone?

Thanks again...

If at first you don't succeed....then Skydiving is not for you!

[deadbug 0]

I went to Dacron for my lower steering line this summer for this very reason. I fly a Katana at 2.0 and don't want any supprises at 15ft. Although I can land on rears there may not be enough time to react if a brake line snaps at the wrong time.

Doug