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sammyc

Headdown tandem?

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Some place you will find it very illegal but in others you will find it great fun.
Have seen it done a few times, most of the times where the video should not be made public:P if you know what i mean.


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I've seen some videos of tandems going head down for a few seconds before throwing the drogue. You can see an example in http://www.skydivingmovies.com/ver2/pafiledb.php?action=file&id=1720. I think it's "normal" or at least usual for certain TIs at certain DZs, but I don't think it's normal in general.

Dave



It's normal to look like your going head down when you do a diving exit with a tandem but remember where the relative wind is coming from. in all actuality your belly into the wind.


The world is full of willing people, some willing to work, the rest willing to let them.

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Did you watch the video? That's real live head down, done on purpose, freefly style. :)
But unrelated to the topic i guess...

But here's a couple examples of atmonauti tandems (experienced passengers i assume): http://www.skydivingmovies.com/ver2/pafiledb.php?action=file&id=2693 and http://www.skydivingmovies.com/ver2/pafiledb.php?action=file&id=3717

Dave

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I haven't seen this video, but I am in france right now and was asking a tandem master about that (because I have seen it on french vids). He said ya they do it all the time, at the DZ I overheard another tanem master telling a guy he just took up that if he does a tandem again they will go head down. The TI also said that it is very easy to take a passenger headdown.

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Very much against the rules in the United States. In this country, the Basic Safety Regulations 2-1(E)(4)(e)(3) says: "Intentional back-to-earth or vertical orientations that cause tandem freefall speeds exceeding that of droguefall are prohibited."
.
Tom Buchanan
Instructor Emeritus
Comm Pilot MSEL,G
Author: JUMP! Skydiving Made Fun and Easy

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I am no expert but is head down tandem just an accident waiting to happen?



Yup.

There is much greater potential for instability if the student doesn't cooperate throughout the entire freefall. Side spins happen in freefall, and are a greater risk when freefall is extended with differing orientations. The extra speed increases the potential for a student (or instructor) freefall injury such as a shoulder dislocation. There is an increased risk of premature openings. If there are any problems with the drogue or drogue release, the tandem pair will already be at tandem terminal, and that increases the risks associated with either main or reserve openings. Head down is so much faster than flat freefall, and that loss of time requires faster emergency procedures on the bottom end. Deploying the drogue at tandem terminal reduces the life of that component and can cause catastrophic drogue failure.

From the Sigma Manual:
Quote

Deploy drogue within 5 seconds after exit:
This gives the Tandem Instructor time to feel the stability of freefall, but is before terminal velocity, saving wear and tear on the parachute system.
If the drogue is deployed during Tandem terminal (170+MPH), and functions properly it will take approximately 10 seconds to reduce your terminal velocity to normal (120 mph). Therefore, you should wait at least 10 seconds after deploying the drogue in this situation before you deploy the main by pulling the drogue release handle.
In other words, if you want to deploy the drogue after Tandem terminal is reached, you must allow two thousand feet after deploying the drogue for deceleration before pulling the drogue release handle and deploying the main. This is not to say that the system will not work if you release the drogue immediately after deploying it at Tandem terminal. It is to say that the faster you go, the harder the openings, which will surely reduce the life of the parachute system.
Lastly, deploying the drogue approximately 5 seconds after exit will allow you time to assess a drogue malfunction situation, thus giving you ample time to deploy the reserve before Tandem terminal has been reached.



Tandem is really a teaching tool. While the risks of conventional tandem jumping are lower than other training methods, tandem jumping has more injuries and fatalities than amusement park rides, even under the best of circumstances. If the passenger wants to learn about skydiving, tandem is the best way to go. If the passenger wants a thrill ride, an amusement park is a better and safer option.

The risks associated with tandem head-down are significant. A student is not capable of assessing those risks, and thus is not capable of offering an informed consent.

I've done my share of tandems (rated on the Racer, Strong Dual Hawk, conventional Vector, and Sigma---about 1,000 tandems). I know it sometimes gets boring for the tandem instructor, but that is not a good reason to add risk to the student. It's far better to use the potential of freestyle or high speed jumps as a means of motivating a first jump student to complete the full training program, than to give those experiences away on a higher risk tandem.
.
Tom Buchanan
Instructor Emeritus
Comm Pilot MSEL,G
Author: JUMP! Skydiving Made Fun and Easy

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Head down is so much faster than flat freefall



But is it though? Belly to earth you only really have one person's surface area providing most of the drag and that can easily get to 180 mph drogueless. Whereas head down, you have two (in profile at least) plus the rig. Does anyone have any empirical results? For the cameraman to stay with it reasonably closely and in enough control to safely take those pictures I'm guessing that it was approximate head down speeds. I'm not suggesting it's a good idea; just curious...
Skydiving Fatalities - Cease not to learn 'til thou cease to live

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Head down is so much faster than flat freefall



But is it though? Belly to earth you only really have one person's surface area providing most of the drag and that can easily get to 180 mph drogueless. Whereas head down, you have two (in profile at least) plus the rig.



You are probably close to correct. The point regarding speed is that tandem terminal is to be avoided with students unless there is a compelling reason to go there. That's true whatever the orientation. Tandem terminal is faster than a normal flatfly, and faster than droguefall.

Speed alone is a problem, but adding the vertical orientation adds more problems than just speed, as noted in my previous post.
.
Tom Buchanan
Instructor Emeritus
Comm Pilot MSEL,G
Author: JUMP! Skydiving Made Fun and Easy

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"Intentional back-to-earth or vertical orientations that cause tandem freefall speeds exceeding that of droguefall are prohibited."


By the way this is worded, you could argue that intentional flips on exit are prohibited.



>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Not prohibited, just frowned upon.
Many DZOs consider tumbled exits to indicate poor TI skill, poor knowledge of relative wind, poor exit planning, etc.

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you could argue that intentional flips on exit are prohibited.



Prohibited is a very prohibiting word. :P

I think it's safe to say that tandem manufacturers intend that thier rated TIs will make every effort to exit an aircraft with the intent of presenting the pair to the relative wind as cleanly as possible to ensure optimum chances for a clean stable drogue deployment 3-5 seconds after exiting the aircraft.

That said, a 3 quarter backloop is considered to be a good tandem exit out of a tailgate aircraft. Is it technically an intentional flip out the door? Sure, 3 quarters of one anyways, but its done by the TI with the intent of presenting the tandem pair to the relative wind, not done just for fun.

To do an intentional flip out of say an Otter, for fun, is not recommended, and whether it's the DZO watching the video or a manufacturer rep seeing it live in person, people have been grounded for intentional flips out the door.

--
My other ride is a RESERVE.

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Just been watching this brilliant video, one of the TI's in it is constantly doing back flips out of something like an otter. Very proffessionaly shot video.

[/url]http://www.skydivingmovies.com/ver2/pafiledb.php?action=file&id=1458&string=tandem%20spin

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