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My tandem double mal today

 

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SimonBones  (D 28573)

Feb 11, 2007, 5:59 PM
Post #1 of 31 (4513 views)
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My tandem double mal today Can't Post

Hey all! I wanted to post and discuss my tandem double malfunction today because 1) I wanted to make others aware of what happened and 2) more importantly I want feedback from Sigma rated tandem instructors, riggers, or packers if anyone has ever heard of this or had any experience with something like this. I wasn't sure if this post should be in instructors, gear/rigging, incidents, or more than one. Moderators feel free to send this wherever is better.

First, quickly about me. I am new to tandem instruction. I have somewhere about (haven't counted exactly) 60-70 tandem master jumps almost entirely on Vector Sigma equipment. I'm about 6 ft 1 and 150lbs. My passenger was an older man with about the same frame but shorter. This was his first tandem jump and my first for the day. My most recent tandem was from yesterday and I have been tandem mastering for 5-6 months. Before today I have never had a tandem malfunction. I have had 2 unintentional cutaways and 1 demo cutaway on sport equipment.

What happened: There was no video. Normal drogue freefall (as far as I can tell). I pulled my primary release at 5,300ft and had a hard pull. I gave it 3 quick hard yanks total. I have never had any issue with this equipment having anything more than the normal 10lbs pull force. I went to the secondary release and started yanking hard and quickly on that about 3-4 times. I quickly began pulling on both simultaneously as hard as I could for about 3 times. Each time I had pulled, there was some extension of the handle and then a stop. The ball did come away from the housing a few inches.
I pulled my cutaway handle and quickly next my reserve. The drogue instantly tangled with the right side of the reserve lines wrapping them. This did not allow the reserve slider to come down any lower than 2/3 to 3/4 of the way up. The drogue was not collapsed, it was still cocked. Without hesitation I went to work trying to untangle the drogue from the lines. At this point I was just above 2000ft. Because of the nature of the entanglement, the descent rate, and the cocked drogue trailing behind putting tension on the bridle, and altitude I stopped trying to clear the entanglement and went to work trying to bring the entanglement lower by pulling down on the bridal areas I could reach and pumping the brakes hoping this would bring the slider down further and lower my descent rate. At about 1200ft I had gotten the entanglement low enough that the slider was about 1/3 of the way up. I was over the trees at the edge of the landing area and stopped fighting the entanglemet in order to stear the parachute to the landing area. A left 90 and a right 90 (into the wind) brought me to 800ft but over the landing area. I flared as hard as I could but still had a rough landing. Both myself and the passenger were not injured and walked away scratch free. The passenger was oblivious to any problems (I kept telling him he did a good job and cheered him on and so on while the battle was going on).
After carefully taking of the rig and laying it flap side up. Several of us including 2+ riggers and the DZO began an inspection of the system. The drogue release pin was still in place, canopy still in the container. The safety pin was not in the drogue release pin at this time. The secondary handle was pulled and the pin released with relatively normal force.
Confused we kept looking into any causes for this. The top grommet was noted to have an indentation where the safety pin is inserted. This indentaion also existed in the other Sigma rigs but more so in this one. We did not think this is the cause. After quite a bit of discussion the best thing we could speculate was some sort of drogue bridle snag that did not allow the safety pin to be pulled during freefall. I did not notice any snag on myself. The freefall seemed as steady as any other to the best of my recollection.

If anyone Sigma rated, rigger, or experienced Sigma packer has any kind of input or experience with any situation like this that could explain something please share. Is there something we are not thinking of? I would be glad to answer any questions to put anymore clarity to this situation.

Thanks,
--SimonBones


Miami  (D 17626)

Feb 11, 2007, 7:11 PM
Post #2 of 31 (4448 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

Well shit...I take a weekend off and look what I miss! If you're out next weekend you'll have to show me the indentation the safety pin is making. Glad you made it out in one piece!


Galante

Feb 11, 2007, 8:54 PM
Post #3 of 31 (4394 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

Simon,
this is Mauricio Galante your tandem examiner
please send this report to Mike "Mad Dog" Miguire at United Prachutes Technology, former relative workshop to take a look at this
i'll be doing some tests here at Deland to see what could cause this and please let me know anything else you found in the system that we could learn from it.
questions:
did you notice any missrouting on the bridle?
did you notice any missrouting on the release pin?
does the identation noted is enough to avoid a normal drogue release sliding?
great job and blue skies
sincerely,
M.G.
In reply to:


efs4ever  (D 7014)

Feb 11, 2007, 9:12 PM
Post #4 of 31 (4386 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

Do you have a long or short closing pin? It's possible for the (older version) longer pin to get trapped by the disk if it's outside the pin tip protector and facing up. The force traps it between the disk and the closing flap.

If it's under the closing loop grommet that's another way to total.

Twists in the pin pulling line can also increase the pull force.

Way to go on EP. Smile ( Beer! )


luckysideburns  (D 28597)

Feb 11, 2007, 11:16 PM
Post #5 of 31 (4349 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

nice job man, tho i believe this is a "first" were everyone else owes YOU a beer!
congrats on keeping the passenger calm and staying cool despite the situation. let us know any developments :)
blue ones man,
-nicky


rhys  (D 95)

Feb 12, 2007, 12:50 AM
Post #6 of 31 (4336 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

You Handled that situation very well!

Try taking note on how your packer stuffs the excess bridle after stuffing the drouge in the BOC?

could have been hung up there somehow?

well done on your reactions though!

Blues,

Rhys


SimonBones  (D 28573)

Feb 12, 2007, 2:43 AM
Post #7 of 31 (4320 views)
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Re: [Galante] My tandem double mal today [In reply to] Can't Post

While gear checking before the jump, I noted the safety pin to be pulled out about 1/3 of the way. I tried to push it back in but it was in that position from the bridle being tucked up behind the right flap while routing to the pouch.
While on the ground afterwords, the safety pin had been pulled out. There was no obvious twisting in the release pin line. That was noted afterwords by a rigger who was on the scene for immediate inspection.
As far as pin lengths I'm not sure, my experience with tandem systems is limited. I will have to get one of the more senior instructors to check that out.
My best thought is that after routing the bridle to the pouch however it was tucked may have caused a hangup in the safety pin, but again, the safety pin was released on ground inspection. It could have possibly released while struggling with the bridle to clear the entanglement.

How possible is it that hard pulls on the pin for these other reasons we've been discussing to clear after the reserve is out. I've seen before in pilot chute in tow situations that not cutting away leads to the main becoming loose and falling out and inflating. Could the tandem reserve opening lead to clearing whatever situation caused the hard pull?


Premier Tonto  (D 515)
Moderator
Feb 12, 2007, 6:56 AM
Post #8 of 31 (4249 views)
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Re: [luckysideburns] My tandem double mal today [In reply to] Can't Post

In reply to:
nice job man, tho i believe this is a "first" were everyone else owes YOU a beer!

Nope. He owes ME beer.Wink

http://www.dropzone.com/..._reply;so=ASC;mh=25;

t


jkbernstein  (D 29379)

Feb 12, 2007, 9:15 AM
Post #9 of 31 (4178 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

Simon -

I'm a little calmer now than when you told me about this last night. You did a great job saving your own life, and that of your student. I am so thankful that you're okay; it would really, really suck if you were dead.

Since (as you know) I'm not a TI, I'm not very familiar with the rig you were jumping. There was recently a thread in this forum titled "sigma deployments" - this sounds like they are discussing the same issue. Take a look at it...


Premier Tonto  (D 515)
Moderator
Feb 12, 2007, 9:21 AM
Post #10 of 31 (4171 views)
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Re: [jkbernstein] My tandem double mal today [In reply to] Can't Post

Link to the thread you mentioned..

http://www.dropzone.com/...;;page=unread#unread

t


Laszloimage  (D 22468)

Feb 12, 2007, 12:44 PM
Post #11 of 31 (4080 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

Years ago I had a similar expirince, except I was able to release the drouge eventualy.
In my case they sent me out for a back-to-back jump (while I was doing video that day) to make a tandem jump. My student was a heavy set (220lbs) lady. Both the tandem rig and and the student were waing for me at the boarding area. I checked the rig wich was packed by one of our packer (poorly trained with my opinion...). and I noticed all the fabric of the main was in the centre of the rig putting more tention
on the closing loop. Further more the two ripcords of the straight pin were twisted 4-5 times and pinched between the groumet and the head of the pin. So I was expecting a harder pull. But it wasn't only harder, it was f$%^n' hard!!! I almost ended up deploying the reserve into the trailing droug 'cause I hit the 4500' hard deck after 7-8seconds trying to pull. But in the very last moment the drouge finally released while I was pulling both handels (altering each side, hard jerks).
The nightmare wasn't over just yet...When I went for the brakes it released one side but didn't on the other side. The 220lbs 65yrs old lady wasn't gonna help either. So I had to let go the toggle on the released side, go into a spiral, and free the other brake with my two hands. (that brake wasn't set properly either)
After that I made a new rule: If it's not my pack job or not pack job supervised by me NO JUMP! No back to backs! Period!
I can imagine something similar happaned to you as well. The other thing could have been if the tip of the closing pin wasn't placed under the ritainer tape. This can result the pin rotate and when you trying to pull it actually the pin "getting pulled back into the loop"
It's very hard to imagine that the safety pin stock, but I'm pretty sure someone can make it happen...
In the other hand I think the Sigma tandem system is the best and the safest on the market, but unfurtunately isn't idiot proof. Every prolem I've seen occured with it because of the chaine (more than one) screw ups.
I glad you're alive, obviously you did a great job dealing with the emergency!
-Laszlo-

(I have over 2000 tandems, 1000+ with Sigma 99% of them packed by me)


(This post was edited by Laszloimage on Feb 12, 2007, 12:51 PM)


SimonBones  (D 28573)

Feb 20, 2007, 11:39 AM
Post #12 of 31 (3569 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

After some research and talking with Relative Workshope we think we may have figured out what happend to me. I'm attaching pics of some closing configurations sent by RW. The incorrect way labeled "BadSigma" can cause pull forces of 75 pounds DURING DROUGUEFALL and drouguefall only. After being on the ground (like in my case) there will be no high pull force. Closing this way can pinch the pull line so the force of the drogue during the droguefall gives you a hard pull. Some of you have shared experiances of hard pulls but didn't know why. When doing your gear check look for this. It's very easy to miss and some at our DZ (including some riggers) were unaware of this problem. I hope reading this will save you from a hard pull, reserve ride, or even a double mal.
Attachments: BadSigma.JPG (1.46 MB)
  GoodSigma.JPG (1.28 MB)


billbooth  (D 3546)

Feb 21, 2007, 7:08 AM
Post #13 of 31 (3475 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

Simon:

Sorry you had a hard pull. However, the Sigma system is not that delicate. While as it says in the manual, I prefer the "good Sigma" ripcord twist, the "bad Sigma" routing only increases the pull force by a couple of pounds. What does make a hard or impossible pull, again as it says in the manual, is routing the ripcord pin down under the main loop washer. Otherwise, pull forces with 450 lbs. suspended weight should be under 10 lbs. (The left handle will always seem "harder" than the right, simply because it is in a more awkward position.)

By the way, we do have a military "drogue bundle" double loop which brings pull forces under 10 lbs. with up to an 850 lbs. load.


tsalnukt

Feb 21, 2007, 2:32 PM
Post #14 of 31 (3430 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

Yeah dude, I have to agree with Bill. I have a couple thousand jumps on sigmas and have jumped the "bad" looking one with little or no diffrence in pull force. I would be willing to bet that the closing pin got stuck under the top of the disk or like someone else said under the closing loop disk. Only advise I have is do a good preflight everytime... and don't ever rush it. Oh yeah...always carry a big hook knife. You never know when your're gonna need it


tqsmile  (D 855)

Feb 22, 2007, 7:54 AM
Post #15 of 31 (3378 views)
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Re: [tsalnukt] My tandem double mal today [In reply to] Can't Post

I agree,always have that hook nife close by


Laszloimage  (D 22468)

Feb 22, 2007, 1:30 PM
Post #16 of 31 (3348 views)
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Re: [tsalnukt] My tandem double mal today [In reply to] Can't Post

I agree. If it's the "Bad Sigma" version, that will ad only a few ponds. But please chek my previous post, when I had a really hard pull the problem which is shown in the picture was only one out of the long list of problems (bad pack job, heavy student etc...) ...and they all added up top of the other. The result was an extremly hard pull.
But of course it was not the problem with the Sigma system, it was a problem of slappy unproper pack job.
-Laszlo-


RTB  (D 582)

Feb 25, 2007, 3:03 AM
Post #17 of 31 (3228 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

 
Hi, we have had a reserve ride on a Sigma that I believe could have the same cause as your. The difference being that the reserve deployment was clean and that the safety pin was still in place after landing. Even though we could not duplicate the same situation later what happened was the safety pin did not release even though the drouge was out. Under very special circumstances the pin will lock leading to an impossible release. In your case the safety pin could have released once the tension was gone. In our case it was easy to lift the safety pin once on the ground.


JJohnson  (D 22675)

Mar 5, 2007, 7:15 AM
Post #18 of 31 (3002 views)
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Re: [SimonBones] My tandem double mal today [In reply to] Can't Post

All I can say is good job brother, good job. Well done in dealing with the problem and keeping the student sane and safe.


josheezammit  (D 28519)

Mar 6, 2007, 8:53 AM
Post #19 of 31 (2932 views)
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Re: [JJohnson] My tandem double mal today [In reply to] Can't Post

Is what Simon did the correct emergency procedures for the inflated drogue in tow malfunction that he is describing? Am I not seeing the big picture? Unimpressed


OnYourBack  (D 25190)

Mar 6, 2007, 9:55 AM
Post #20 of 31 (2920 views)
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Re: [josheezammit] My tandem double mal today [In reply to] Can't Post

Since you can't cut away the drogue, the only option left with one in tow is to go reserve and hope it clears the drogue. It normally does.


josheezammit  (D 28519)

Mar 6, 2007, 10:25 AM
Post #21 of 31 (2909 views)
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Re: [OnYourBack] My tandem double mal today [In reply to] Can't Post

and you don't cutaway right?


OnYourBack  (D 25190)

Mar 6, 2007, 10:49 AM
Post #22 of 31 (2904 views)
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Re: [josheezammit] My tandem double mal today [In reply to] Can't Post

You are correct, cutting away is unnecessary. It doesn't appear that doing so made this incident worse though.


josheezammit  (D 28519)

Mar 6, 2007, 10:54 AM
Post #23 of 31 (2900 views)
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Re: [OnYourBack] My tandem double mal today [In reply to] Can't Post

but could it have?


OnYourBack  (D 25190)

Mar 6, 2007, 11:25 AM
Post #24 of 31 (2895 views)
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Re: [josheezammit] My tandem double mal today [In reply to] Can't Post

I'm sure you could dream up a situation that cutting away would complicate the problem such as free risers fouling the reserve lines. There have been discussions in the past about whether to teach students to cut away before the reserve with pilot chute in tow malfunctions. I guess the arguments for both sides would be the same.


josheezammit  (D 28519)

Mar 6, 2007, 11:29 AM
Post #25 of 31 (2893 views)
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Re: [OnYourBack] My tandem double mal today [In reply to] Can't Post

then my next question is and if the almighty booth is listening i would like his answer too, what it the way that Relative workshops/UPT trains their TM's to initiate their emergency procedures for this unique situation.


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