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Eule

Tunnel cutaway training?

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All,

I originally posted this at the end of another thread. There haven't been any replies (maybe that's a
hint) but I decided to post it as its own thread anyway. I'm curious to hear what the problems and
benefits that experienced tunnel flyers/operators might see in this. If this is a completely dumb idea,
feel free to tell me that as well. :)

This originally came about when Paulipod (Bodyflight Bedford) said they had a tunnel rig with a BOC
as they do a lot of AFF training there. I ran with that idea to wonder if you could do useful cutaway
training for students or experienced jumpers in the tunnel.

Keep in mind I am a low-jump-number student, not an instructor of any kind.

At the DZ I go to, the hanging harnesses have both main and reserve risers, and a working 3-rings.
When students are practicing cutaways, most of the practices are done with a dummy cutaway pillow
handle - no cables on it. However, for one cutaway, the instructor replaces the dummy handle with
the "real" handle with cables to the 3-rings. When you pull it, the 3-rings releases and you drop a few
inches, until you are caught by the reserve risers. It's not exactly what you would feel in the air, but it
gives you a feel for what pulling the cutaway handle is like.

I wonder if something like this could be arranged in the tunnel, to give students (or anyone interested)
a more 'realistic' cutaway experience? You could have a tunnel rig with a relatively short set of main
risers and a much longer set of reserve risers. Both sets would be fixed to a support in the upper part
of the tunnel. The student would get into the rig, and then the operator would turn up the air until the
student is in "free fall" - belly to earth and not hanging from the risers. The student would do a practice
ripcord pull/pilot chute throw. When the operator observes this, he can either leave the air turned up
(high speed mal) or turn it down substantially (low speed mal). When the student recognizes the mal
and pulls the cutaway, the operator turns the air back up to "free fall" if it was down - the student is
going back into freefall. The student will fall somewhat, but hopefully not to the end of the reserve
risers. Once the student pulls the reserve ripcord, the operator turns down the air, and leaves the
student hanging from the reserve risers.

Problems: The student either has to be briefed on what to expect - how to "know" he's got a
malfunction by what the air is doing - or given some signal. Perhaps something as simple as a lamp
mounted on the thing that the risers are mounted to - if you practice pull/throw, look up, and the
lamp is on, you have a malfunction. The advanced version would be to have a TV monitor up there
playing one of the "you pulled, looked up, and saw *this*" videos. The monitor would have to be
hardened against 120+ mph airflow, though.

The main risers need to be tacked to the reserve risers just above the three-rings. Otherwise, when
the student cuts away, the main risers are free to flail about at their full length in the tunnel.

If your tunnel is a sucker, the idea of having loose cutaway handles/ripcords is probably not great
(fan/motor damage). Even if it's a blower, it's probably bad form to shoot a handle out the top and
have it land in the car park.

How does the student get into the harness in the first place? The risers need to be anchored several
feet off the net to allow the student to "go back into freefall", but that makes it hard for them to get
into the harness. You could bring a ladder into the tunnel, have a second entry door higher up, or
maybe install a winch for the riser anchors - student dons rig, stands on net, instructor connects
risers to winch, student is hauled up to the appropriate height.

Also, when the student is done with this exercise, he is hanging in a harness a few feet off the net.
Maybe an instructor can help him get out, or with the winch, he could be lowered to the net.

This requires some kind of support for the risers that is inside the airstream. You probably wouldn't
want to leave this there for general flying. On the other hand, you would probably offer "cutaway"
training relatively infrequently, and it could be done at the beginning or end of the day, to avoid
losing too much time while the support is installed or removed.

Eule
PLF does not stand for Please Land on Face.

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Practicing cutaway procedures on tunnel rigs may be closer than you think.

You will be able to practice staying stable when you pull but there is no way to simulate a malfunctioning main in the tunnel.
Tunnel Pink Mafia Delegate
www.TunnelPinkMafia.com

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i can see you could put something together to practice pulling your handles, but i don't imagine Paul or other owners would be too happy with people letting go of things and them going through the prop! you'd have to be pretty confident they were retained properly....
Never try to eat more than you can lift

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Yup, already got that on lock down ;)

It's tough enough to take a camera in let alone things that could be flying all over the place. I make sure that there is virtually no way it can go a muck. Taking things in a tunnel is def. a privilege that is not taken lightly.

Edited to add: not sure if this project is still on going, it hit some major road bumps around the end of July. If things do come to fruition, it should be a fun little project.

Also, no amount of tunnel cut away training could replace a hanging harness or actual sky experience.
Tunnel Pink Mafia Delegate
www.TunnelPinkMafia.com

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Eule,
I don't mean to dismiss your idea outright, but here are a few other issues that came to mind:
1) I don't think the tunnel can change speeds fast enough to accommodate the scenarios that you describe.
2) Time is not cheap in a tunnel - I've seen threads where people were unhappy about loosing 5-10 seconds per session due to the time involved in one person exiting the tunnel, and the next person entering. Getting someone out of the harness, and the next person in is going to take a significant chunk of time. That translates to more $$ per simulated cutaway. It will be WAY more expensive than a hanging harness, and I question whether it would really be more realistic.
3) Mounting the supports would be quite a challenge, especially in a SkyVenture style tunnel, where the walls are basically smooth, and the tunnel operator wants it to stay that way to keep things as energy efficient as possible (rough things in the air flow = drag = more energy required to run the tunnel = more $$ for the utility company, less for the tunnel owner. And we all want the tunnel owners to be happy, so the tunnels all stay open!)

I think there are better options that are way less complicated. If you want a realistic experience, get a rig set up with 2 reserves, and go do an intentional cutaway!

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LOL - what he said.
The tunnel is a good training tool but i think this is probably overcomplicating things just a weeny bit....



The scenario described in the first post was a bit overboard, but at the Fort Bragg tunnel we have always taught pull sequence and cutaways with dummy rigs. The handles are attached with bungee cord. It might not be feasible to waste that much time in a civilian tunnel due to the prices people pay in those things, but being able to take the time to train a guy all these techniques while insisting he maintain stability and maintain his position in the cone, is a tremendous confidence booster. Particulary when the guy is going to be expected to carry a ruck, weapon, and O2 in less than 20 jumps in some cases. We train all of our students in the tunnel to that standard both slick and completely loaded up.

Chuck

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Thats hardcore - i met a load of guys at perris who were doing night jumps fully loaded up out of the skyvan. Much as i love trying new things.... you can keep that one!!! (especially after i saw some of their landings!)

I was on one load with them during the day and i didn't envy them waddling everywhere one bit.......
Never try to eat more than you can lift

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The Airborne and Special Operations Test Board were in the Bragg tunnel yesterday testing some sort of pilot chute. They were, no shit, deploying their dummy rigs in the tunnel. Let me clarify: just the PC and bridle; the containers held dummy main bags which are locked in the container. Yes, they were getting immediately pinned to the roof. My roomate Simon ("porkchop" on here) was there watching the fiasco. Funny, huh?

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The Airborne and Special Operations Test Board were in the Bragg tunnel yesterday testing some sort of pilot chute.
Quote



Is this something new that we might be seeing in Group sometime soon?

History does not long entrust the care of freedom to the weak or the timid.
--Dwight D. Eisenhower

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The Airborne and Special Operations Test Board were in the Bragg tunnel yesterday testing some sort of pilot chute. They were, no shit, deploying their dummy rigs in the tunnel. Let me clarify: just the PC and bridle; the containers held dummy main bags which are locked in the container. Yes, they were getting immediately pinned to the roof. My roomate Simon ("porkchop" on here) was there watching the fiasco. Funny, huh?



SEE! SEE? They do go up when the parachute opens. I KNEW IT

...
Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

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They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers.
But they also laughed at Bozo the Clown. -- Carl Sagan



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daniel_owen_uk> In a real emergency when you cut away you will go into subterminal freefall,
daniel_owen_uk> how do you go to subterminal in a tunnel?



Good point. Assuming you don't change your body position at all, there will probably be a rather
narrow range of speeds (in the tunnel) that don't end up with you on the net or up by the fans.

Quote

dzjnky> 1) I don't think the tunnel can change speeds fast enough to accommodate the
dzjnky> scenarios that you describe.



I don't know for sure, but it seems reasonable, particularly when you're trying to reduce speed.
With some motors and motor drives, you could electrically brake the motor, but there is probably
a limit to how much you can accelerate the prop before it comes apart. You might be able to do it
with vanes ahead of the test section, but then you really are getting into the land of "lots of
complication for little benefit", IMHO.

Quote

dzjnky> It will be WAY more expensive than a hanging harness, and I question whether it
dzjnky> would really be more realistic.



I was somewhat thinking that this would be offered relatively infrequently - one afternoon or one day
would be set aside as "cutaway training day." Part of this is the time to set up the tunnel for it.
However, it's true that if the owner could be making $10 a minute on regular flyers, he won't want to
make very much less than that on special training, which would mean you'd get to pay for all of the
time climbing in, getting set, etc.

Quote

dzjnky> 3) Mounting the supports would be quite a challenge,



I think this would be pretty easy to overcome. I am thinking something like holes in the side of the
tunnel (with suitable reinforcement) threaded for large countersunk socket-head screws. Most of the time, these have countersunk socket-head screws in them, that fit flush with the wall and offer very
little drag. When you want to put the supports in, you take these out, put a mounting plate over the
holes, and screw regular hex-head bolts throught the plate and into the threads. I did mention that
this was unlikely to be a quick process.

Quote

SkymonkeyONE> [....] being able to take the time to train a guy all these techniques while
SkymonkeyONE> insisting he maintain stability and maintain his position in the cone, is a
SkymonkeyONE> tremendous confidence booster.



This is a part of what I was after. Teach people that cutaways aren't as big of a deal as they might
otherwise think. You don't want them to get so relaxed that they will cut away if the colors on the
main clash with their jumpsuit, though. Like I said initially, I'm not an instructor, so I don't know how
much of a problem this really is with the entire spectrum of jumpers.

I think that the kind of training SkymonkeyONE described is probably about what Paige is describing -
have handles on the rig that work and can be pulled out, but which are fastened to the rig so they
don't cause mayhem in the tunnel.

Quote

SkymonkeyONE>Yes, they were getting immediately pinned to the roof.



You left out the link to skydivingmovies.com. (Yes, I realize that it would be nearly impossible to take
such a video and then show it to the public.)

As a reply to the "why not just go jumping" question, I guess I was initially thinking of this as something
somebody would do after they already had a few jumps, something like a canopy control course. Even
if this were practical, I'm not sure you'd want to do it as part of a FJC.

Thanks for the replies!

Eule

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The Airborne and Special Operations Test Board were in the Bragg tunnel yesterday testing some sort of pilot chute. They were, no shit, deploying their dummy rigs in the tunnel. Let me clarify: just the PC and bridle; the containers held dummy main bags which are locked in the container. Yes, they were getting immediately pinned to the roof. My roomate Simon ("porkchop" on here) was there watching the fiasco. Funny, huh?



was this some of ratboy's shit?
:D:D:D:D
Scars remind us that the past is real

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LOL - what he said.
The tunnel is a good training tool but i think this is probably overcomplicating things just a weeny bit....



The scenario described in the first post was a bit overboard, but at the Fort Bragg tunnel we have always taught pull sequence and cutaways with dummy rigs. The handles are attached with bungee cord. It might not be feasible to waste that much time in a civilian tunnel due to the prices people pay in those things, but being able to take the time to train a guy all these techniques while insisting he maintain stability and maintain his position in the cone, is a tremendous confidence booster. Particulary when the guy is going to be expected to carry a ruck, weapon, and O2 in less than 20 jumps in some cases. We train all of our students in the tunnel to that standard both slick and completely loaded up.

Chuck




And I've done the same sort of training with the military in SkyVenture type tunnels. It's just expensive for the average Joe or Jane to do the same sort of training, and generaly isn't worth it.
----------------------------------------------
You're not as good as you think you are. Seriously.

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