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RoadiJeff

Tandem Jump Problem

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Hi guys (and gals). I have a question about an incident my wife encountered last fall when she did her second tandem jump. She was emotionally freaked out about it for several weeks after it and refuses to ever jump again. Please overlook some terminology if I don't use the right words. I've never been skydiving and have absolutely no desire to ever do so. :)
Anyway, they jumped out at 10,000' and all seemed well. I was watching them through binoculars and it looked like they were dropping like a rock - very fast. I know they free-fall for the first 5,000', so I didn't think anything about it.

After they got back to the hanger the instructor mentioned a problem they had on the way down. I don't know what you call it but the drag chute, or whatever it is called, got hung up in the dead air space behind them and did not fully deploy. They apparently were dropping much faster than normal.

He finally got it free and they slowed down but I gathered from his description that it was because he hadn't flung it hard enough away from him initially to catch the air. My wife would not have known anything had gone wrong if he hadn't mentioned it when they got back.

Anyway, how serious was this mishap? Was there ever any real danger or just the fact that they didn't spend as much time in the air as they normally would have? My wife seems to think that she almost died. Depending on the replies, I will either print them out and show her or keep this thread a secret from her. Thanks for your time.

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That sounds like what is called a "pilot chute hesitation", where, as you said, the pilot chute (drogue chute in this case) gets into the still air behind the jumpers. It's a minor problem, especially with a tandem where the drogue is deployed right out the door. There's all kinds of time available to clear it, and it usually does so itself in just a second or two. For experienced jumpers who deploy much lower, and don't have as much time to fix things, it's a bit scarier. But for a tandem, it's nothing much for a tandem passenger to really worry about. Sounds like the tandem master handled it just fine.

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SuperMouse, I'm guessing you are not tandem rated.

From the Sigma manual (but pretty standard across most tandem systems),

Quote

C. Un-inflated drogue

PROBLEM: Drogue has been deployed and is partially or completely uninflated.
REACTION: If the drogue does not inflate within six to eight seconds, pull either one of the drogue release handles to initiate main canopy deployment.
ANALYSIS: An uninflated drogue has enough drag to deploy the main canopy although it will take longer than normal to do so. If you wait longer, your velocity will increase. Higher velocities may produce a higher opening shock.


Skydiving Fatalities - Cease not to learn 'til thou cease to live

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I'll give this a shot too.

It might have been serious, it might not have. We just don't know for sure.

As for skydivers falling like a rock, unless you are used to seeing jumpers drop at 120 mph you wouldn't know if they are doing 120 or 160. (Without the drogue being fully deployed one would have the weight of two people but the drag of closer to one person since the two people are roughly stacked ontop of each other. Therefore they would accelerate to a faster speed.)

The drogue might be collapsed due to a packing problem or some rather unusual equipment failure. The jumpers would fall faster but the main canopy should open normally even if somewhat delayed after pulling the drogue release to open the main canopy. There would only be a small chance of needing to use the reserve parachute. The drogue might even fix itself in the wind blast with no further action needed.

It is also possible that the drogue was caught up on something and thus didn't deploy for some time. That's rare but it does happen from some time and is considered more serious. If the instructor doesn't get the drogue toss and timing of it right, while in the right body orientation, it can blow into the dead air ('burble') and then catch on something, or just blow into something. The drogue could catch on the equipment, or wrap around say the instructor or student's leg.

An instructor will get a serious critiquing if that sort of thing happens, as one does learn how to deploy it properly while in the proper body orientation. That being said, every instructor has had a poor drogue toss from time to time that had an increased risk if catching on something.

Having the drogue catch on something is serious. Typically it can be freed by shaking it off or just having it come off on its own. That would get the instructor's heart rate up but be dealt with within 10 seconds and not last the whole freefall.

If the drogue cannot soon be freed, the reserve parachute can be activated, and indeed that's the standard procedure. One prefers not to do that while other stuff is flapping about behind oneself - there is a small risk of an entanglement (which is BAD since you're out of parachutes) - but usually it should work out fine, although possibly with a hard opening if there's extra speed built up.

[Note to skydivers: I'm not getting into the finer details of a drogue in tow that's uninflated vs. inflated, as it wasn't clear anyway what the speed was.)

I'm guessing the incident was probably not so serious unless your wife for example noticed herself hanging steeply head down the whole freefall or was spinning uncontrollably or something, that would indicate that the instructor didn't have things under reasonable control.

Also, if the instructor deployed the main parachute at about the normal altitude, that also suggests things might well have gotten fixed up and were back to normal. If you have a really serious problem and can't fix it, roughly speaking you deal with it and get one parachute deployed and don't wait for extra speed to build up even more or wait for normal deployment altitude.

So for things getting fixed and the dive going back to normal, that might be from a collapsed drogue uncollapsing itself, or the drogue caught in the burble for a bit but then deploying normally. Things like that aren't that serious but still a jump that had a problem, from the instructor's viewpoint.

So again, probably it wasn't a serious problem, but a skydiver can always think through all sorts of possibilities that they have to consider, from dire to minor.

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It seems to me your wife didn't "almost die" but if almost anything she almost experienced a hard opening. You are forgetting that even in the event of a total malfunction on the main, they still have a reserve parachute which would open a lot harder (faster), especially at a tandem terminal. Also, you and your wife should rest easy knowing that the tandem rig would have an AAD (automatic activation device) that is a computer based device that senses fall rate and altitude and if the instructor did nothing at all the AAD would activate the reserve deployment sequence as a failsafe at a predetermined altitude.

Your wife didn't almost die. She went skydiving.
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RoadiJeff



Anyway, how serious was this mishap? Was there ever any real danger or just the fact that they didn't spend as much time in the air as they normally would have? My wife seems to think that she almost died. Depending on the replies, I will either print them out and show her or keep this thread a secret from her. Thanks for your time.



Tandem instructor here, but certainly not the most experienced, but I will share my thoughts.

Your wife didn't have a mishap but for sure there was real danger the second she decided to strap herself in to an airplane with the eventual goal of jumping out of it. Skydiving is managed risk, jumpers die, and yes with less frequency sometimes tandem pairs die.

Your wife experienced a scenario outside of a perfect dive flow which posed a potential hazard, but I hesitate when using the word experienced because outside of her instructor mentioning it she wouldn't have noticed anything.

My guess on what happened, the drogue got stuck in the dead air above the pair, and inflation was delayed compared to a typical tandem jump. A tandem pair has a big burble, basically dead air above them. That is why tandem instructors are trained to make positive drogue throws while stable, out and away, into clean air.

A bad drogue throw can get the drogue stuck in the burble, often plastered against the instructors rig and back, or dancing in the unclean air of the burble before finally deploying. It increases the risk of a high speed deployment. It also increases the risk of entanglement between the pair and the drogue bridle.

An instructor can go a whole season, or multiple years, without a single bad drogue toss, but they are human and can mess up, and they can be caught off guard when a student suddenly changes their body position.

It happens, the instructor deals with it.

Her instructor dealt with the problem appropriately, they got an open main parachute.

My biggest wonder here, is why he informed your wife. It didn't add to her experience. Why bother mentioning it when the issue was dealt with, the student didn't notice, and you weren't going to take the time to fully explain what happened.

I would have given her a high five, welcome to skydiving, and kept my mouth shut.

Tell you wife congratulations on her jump. If she enjoyed the experience before Mr. Flappy Lips planted that seed of doubt then she should consider jumping again.
"The restraining order says you're only allowed to touch me in freefall"
=P

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cpoxon

SuperMouse, I'm guessing you are not tandem rated.

From the Sigma manual (but pretty standard across most tandem systems),

Quote

C. Un-inflated drogue

PROBLEM: Drogue has been deployed and is partially or completely uninflated.
REACTION: If the drogue does not inflate within six to eight seconds, pull either one of the drogue release handles to initiate main canopy deployment.



Heck, 6 to 8 seconds IS a long time compared to regular jumping. If a belly jumper deployed at 2,500 feet and had a pilot chute in tow, he sure as heck can't afford to wait 6 to 8 seconds before taking some action. In whuffo terms, 8 seconds may not seem like much. But in skydiving malfunction terms, and in comparison to solo skydiving opening altitudes, 8 seconds really is a "long" time.

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Fireplug


Heck, 6 to 8 seconds IS a long time compared to regular jumping. If a belly jumper deployed at 2,500 feet and had a pilot chute in tow, he sure as heck can't afford to wait 6 to 8 seconds before taking some action. In whuffo terms, 8 seconds may not seem like much. But in skydiving malfunction terms, and in comparison to solo skydiving opening altitudes, 8 seconds really is a "long" time.



The two aren't comparable. You're talking about drogue inflation after exit at full altitude, vs main initiation while you're in the basement.

If I'm doing a solo hop and pop at 13k, I'd certainly allow for more time to evaluate and respond to a PC in tow, than if I got one at the bottom end of a jump.

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yoink

***
Heck, 6 to 8 seconds IS a long time compared to regular jumping. If a belly jumper deployed at 2,500 feet and had a pilot chute in tow, he sure as heck can't afford to wait 6 to 8 seconds before taking some action. In whuffo terms, 8 seconds may not seem like much. But in skydiving malfunction terms, and in comparison to solo skydiving opening altitudes, 8 seconds really is a "long" time.



The two aren't comparable. You're talking about drogue inflation after exit at full altitude, vs main initiation while you're in the basement.

If I'm doing a solo hop and pop at 13k, I'd certainly allow for more time to evaluate and respond to a PC in tow, than if I got one at the bottom end of a jump.

Right, so relatively speaking, the high pull has "lots" of time to deal with a problem, compared to a hard deck pull.

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yoink

I might have misunderstood the point of your initial post. I thought you were saying the 6-8 seconds recommendation was too long.



Oh no, not at all. I was just pointing out that "long" is a matter of perspective, depending upon what type of jump you're making. :)

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Wow, thanks for all of the replies, everybody. I was following the thread and there were over 1,000 views within the first 24 hours. This is a very active place.

Here's a little more on how we learned that there had been a problem with my wife's jump. The instructor was wearing some type of data recording device that records the maximum speed achieved during the jump. I think he had to plug it into a computer when they got back to the hanger to d/l the data.

I don't remember the exact number but I think it was in the 150-something mph range. He said he thought they were going faster, closer to 170. It was then when we heard him talking back and forth with the ground crew about the speed.

Anyway, I told my wife about the thread and I gave her a brief summary of what most of you said. She appreciated the comments but she says she is done with skydiving. It is not even open for further discussion with her on ever going again. I guess it was something on her bucket list. She went twice, which is two more times than I'll ever go.

We're climbing Devil's Tower in 2016, so we do still like to do a few exciting things. The climb is one of the things on my bucket list.

Thanks again, everyone. :)

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Altimeters that measure free fall speeds are very common; I wear one on every jump. For perspective, I am 160+ pounds with all my gear on, and I can easily fall 150-170mph by myself, in a stable, belly-to-earth body position (okay, 160-170 is not "easy" but I do it often to keep up with students).
150+ is not super fast in skydiving terms. It is faster than ideal for tandem skydives, where the little parachute (drogue) is used to slow things down and add stability.

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