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Tandem malfunction

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Hi there!

As a new tandem master, I'm wondering what is the malfunction rate in tandem jumping; I would be glad to read your personal experience or your DZ's in that matter. By malfunction I mean problem such a malfunctionning main with or without a cutaway, a side spin or any kind of close call.

Thanks ;-)

S-P
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Back in the days of F-111 canopies, the tandem malfunction rate was pretty bad, something like one every 300. Mals included: hard pulls, bag locks, streamers, line knots, slider hang-ups, torn fabric and more broken lines! I have 14 reserve rides after problems with F-111 tandem mains and have landed more damaged F-111 tandems than I care to remember?!

Malfunction rates also vary widely from one DZ to the next and one packer to the next. Fortunately sloppy packers don't stay on the pay role very long.

Since we standardized on SET 400s our malfunction rate has dropped dramatically. Much of that improvement can be attributed to softer openings which break fewer lines, tear less fabric, etc.
Nowadays we average less than one malfunction per thousand on SET 400 canopies. Our worst malfunction in 2002 was an end C line wrapped around another C line, two cells in. It flew so badly that I landed it! Ha!
Now it seems that one instructor has all the mals, mostly un-explained high openings.
As long as you take good care of your gear and pull handles in the correct sequence, your malfunction rate should be less than one per thousand jumps.

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In 120-ish jumps on a Vector system with F111 mains I had no cutaways, no hairy openings, one or two line twists (kick-out-able) and one side spin (my fault entirely).

In the same time frame as I did those jumps, the Cessna dz I was at had no tandem cutaways on the dz's gear. We had really good packers who all flat packed the canopies in the exact same way (again, these were all F111 mains).

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"I've got roughly 300 tandems with 2 cutaways and 1 side spin where I could feel the blood going to my head and feet. Good times!"

Was the side spin on a Vector or Strong system?
How common are side spins on Vectors? My impression is that Strong have a larger risk for this.
Is this correct?

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Side spins have nothing to do with what type of gear you're jumping. They occur before drouge deployment. Sometimes the cause is hard to determine but it's usually due to the student with there legs way out in front or improperly tightend laterals (side straps)
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I've got roughly 300 tandems with 2 cutaways and 1 side spin where I could feel the blood going to my head and feet. Good times!

Was the side spin on a Vector or Strong system?
How common are side spins on Vectors? My impression is that Strong have a larger risk for this.
Is this correct?

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John Wright

World's most beloved skydiver

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Excuse my ignorance but what it a 'side spin', what causes it and what do you do about it?

Gus

A side spin is just what it says, spinning on your side. It's a very scary thing. The best way to fix it is to get long, I mean extend your arms and legs straight out. You should try and capture your students legs as well and straighten them along with yours. Arching harder wont fix this one, as a matter of fact, it will probably increase the spin rate. If you can't stop the spin then you have no choice but to throw the drouge and hope for the best.
John Wright

World's most beloved skydiver

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If you can't stop the spin then you have no choice but to throw the drogue and hope for the best.


Is this your plan for drogue-up and drogue-down spins, or have you simplified your explanation for folks not familiar with tandem procedures?

Mark

Yes, I simplified it. If it were drouge down, chucking the drouge could create a whole new set of problems. I would deploy my reserve in that instance.

John
John Wright

World's most beloved skydiver

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Side spins have nothing to do with what type of gear you're jumping. They occur before drouge deployment. Sometimes the cause is hard to determine but it's usually due to the student with there legs way out in front or improperly tightend laterals (side straps)

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Are you sure?
What I heard is that the harness of the Strong system allows more movement up and down on the tandem master. This could definitely effect the body position of the two people together. Creating a "propeller" would be more difficult if you are connected thigh to the student.

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It was my understanding that sidespins were less likely on the new Sigma tandem systems due to where the lower attatchment were, am I off base here?



Not completely sure about that one, but I know that the Sigma is a much more secure fitting rig than the Vector and it puts the student in a more manageable position. I am not familiar enough with the Strong system to make an informed comparison about side spins. I do know that the Sigma is my absolute favorite way to do tandems. You can read my review of it in the gear section of this site.
John Wright

World's most beloved skydiver

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Since side spins are a freefall problem - before you toss the drogue - I doubt if it makes any difference whether you are jumping a Sigma, Vector II, Strong, Racer, Eclipse, Galaxy, etc. tandem rig.

I have only experienced one side spin. The student pulled his knees in front immediately after exit. Next thing I knew we were on our sides accelerating rapidly! After 90 degrees of rotation, I responded by jamming my heels into the tops of his knees. We stopped spinning and flopped belly to earth.
When I relaxed enough to toss the drogue, his knees dropped again and we flipped onto our sides. I jammed my heels into his knees again and flipped us belly to earth again, followed by a rapid drogue toss.
When I relaxed again, he dropped his knees again, so we spent the rest of the freefall with my heels jammed into the tops of his knees.
I never told him how close he came to killing us both and he probably never figured out the bruises on his knees.

Nowadays I do everything I possibly can to plan a stable exit and 95% of my exits are stable. I have also learned to ignore students' legs and concentrate on flying my body. The farther I extend my arms and legs, the more leverage I have, so when students get unstable, I do a huge "X" arch and ignore them.

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I doubt if it makes any difference whether you are jumping a Sigma, Vector II, Strong, Racer, Eclipse, Galaxy, etc. tandem rig.



It was my understanding that the lower attatchment points from the student harness were in a different location on the Sigma student harnesses, which helped prevent the student and instructor from being seperated, resulting in a side-spin.
--"When I die, may I be surrounded by scattered chrome and burning gasoline."

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>The best way to fix it is to get long, I mean extend your arms and
> legs straight out.

The last I heard (about 2 years ago; I haven't done any tandems in a while) is that the recovery procedure is to ball up, trap the student's arms and legs in front of them. This will roll you onto your back and stop the spin from getting any faster. Then start a roll so your drogue side is up. Even if you can't get them all the way over (i.e. they are determined to stick their legs straight out) you can get the spin stopped and the drouge handle into a deployable position.

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What worked for me on the side spin I was in was to basically track out of it - legs straight, toes pointed, arms at the side. Stopped the spin within 4 or so revolutions, got belly to earth and had drogue out by 6000 (exited at 10.5).

The key to avoiding it? Stable exit, throw the drogue. If you're stable and the passengers body position isn't perfect don't worry about it - throw the drogue.

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Hi

done about 300 tandems in the last 18 months..
to daye ive had 2 mals...first was broken A lines and a distorted not keen to fly chute as a result....2nd was a very hard opening that blew a cell and broke more lines than i cared to count at the time

both of these incidents were put down to packing !

best thing ive worked out is that shit does happen and be prepaird for it...know your equipment ...know your reserve drills and know your packer

flipper

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Sorry I was not clear enough.
My solution to side spins is to never get unstable in the first place.
I start by planning my exits so the student becomes a "big banana" with their hands on their chest. Students are told to lean their head on my shoulder and try to kick me in the bum.
I present my belly to the wind with a minimum of rotational momentum. Then I arch my back and extend my arms and legs into the biggest "X" arch I can. The contrast in body positions ensures that I have a huge leverage advantage over the student.
On the 5% of exits where we tumble, I usually delta out of the unstable position. As soon as we are pointed chest to earth, I toss the drogue.
By concentrating on stable exits, I have only had one side spin and that was 6 or 7 years ago.

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Works fine for me too in most cases. Do a bit more ground work with the student 'arms in, head on my shoulder & feet on my bum' - train them for five minutes more and avoid all sort of unpleasant surprises...

However, sometimes they 'forget what the plan was' and become quite a handful...

Tall guys, with long legs and a mind of their own...

I honestly don't know what I'm doing exactly if it happens. I think it can be best described with 'go with the flow*) and exercise maximum opportunism...**)'


*) 'go with the flow' = When you try and arch yourself out of something that starts to make a revolution, and then another one, you are doing something wrong...
**) maximum opportunism = you dont get brownie points for style, you get them for tossing the drogue at the earliest safe opportunity :)


"Whoever in discussion adduces authority uses not intellect but memory." - Leonardo da Vinci
A thousand words...

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I've had two malfunctions in 15 years of Tandem Instruction. I've known folks who have had more. I've also known folks who have had less. I average one out of every 400 jumps for my regular gear and about the same for the Tandem gear.
Mike Turoff
Instructor Examiner, USPA
Co-author of Parachuting, The Skydiver's Handbook

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