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What is a "tailgate" exactly?

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why not on slider up jumps?



From my experience, because on some slider up jumps the tailgate slows the opening to an undesirable degree. On slider up jumps from the bridge here, for example, I do not use a tailgate because I think that yields an unacceptably slow opening from a relatively low slider up altitude.


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1. canopy extraction
2. line stretch
3. slider drops
4. tailgate reefs inner C, D, brake lines, thus encouraging nose first inflation
5. canopy fully opens



The problem is that (3) slider drops, is dependent on the pressure from the control lines (because outward pressure from the control lines is one of the prime drivers of slider deployment). Since the control lines are still constrained until (4), the slider is likely to deploy slower, or, in the worst case scenario, require pumping of the toggles/risers to bring it down.


Another way to approach this question would be to turn it on it's head:

What do we gain from using the tailgate that the slider doesn't already get us?

The slider is probably the best staging and reefing mechanism ever created for a ram air parachute. It is extremely effective at staging the deployment and controlling the lateral spread of the lines (most importantly the control lines). Does adding the tailgate make this an even better managed and staged process? I'm not certain.

Also, recall that the tailgate was developed and tested for slider down use. The opening pressure on the tailgate is likely to be very different on slider down and slider up openings. Further, just as it varies from a PCA to a 4 second slider down delay, it will vary from a 4 second slider up delay to a terminal deployment. I believe the manufacturer determined that the tailgate ought to take 12-14 pounds of pressure to open. Are these numbers going to be the same at terminal? Or at 4 seconds slider up? I don't know, but I expect that there would be some variance, meaning that to make the tailgate truly effective in these situations might require a different closure method (and closure strength).


I'm not saying it's a bad idea to use a tailgate slider up (I use it on longer delays, personally). But I am saying that it won't necessarily work the same slider up and slider down, and that if you want to use it that way, you should think about all the variables that could come into play.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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Dave, to this day, I maintain those are my favorite BASE pictures you've ever taken.
God made firefighters so paramedics would have heroes...and someone can put out the trailer fires.

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I am confused and ignorant.

I picked up a Cruiselite a couple of years ago for low money out of curiosity, that had been 'configured' for BASE. It's in a box.

It has a modification to the upper skin on the centre-tail area, which looks like it is configured for stowing lines. It's about (from memory) 30cm wide, and 15cm deep, and is a pocket with velcro. Never seen anthing like it before or since, but I don't get out much. I just assumed this must be for 'tailgates', and put it away in the History Box.

Does anybody know what it actually is?

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80% chance I'm getting suckered by a troll here, but...

That's a tailpocket. It's for stowing lines, because BASE rigs don't use bags. Any CRW jumper at the DZ ought to be able to explain it to you.

If you want a more in depth discussion, you should start a separate thread.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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thanks for clearing that up. i was thinking both were called tailgates. but didnt want to ask
light travels faster than sound, that's why some people appear to be bright until you hear them speak

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Thanks man. I'm not a troll, just a bit ignorant :)
Regards,

Darren

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great shots. I like how you can see the multi's shadow on the first pic.

Where is my fizzy-lifting drink?

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Regarding the use of masking tape, in especially hot and humid environments (such as the Gulf coast), the tape can bleed glue all over the place within a few days.
Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

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Regarding wet masking tape - when combined with being scrunched-up and wet it becomes extremely strong - easily done by letting the tape get in touch with wet grass and having even the slightest scrunch or twist in the tape.

Try it - take a length of masking tape and put a couple of twists in it, then wet it - try to break it either shear across or along it's length.

g.
"Altitude is birthright to any individual who seeks it"

.

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I am unaware of any cases of lineover with the tape method



I had a lineover on Sunday. Three-second delay slider down. I used 3-4 wraps of one inch masking tape. Unfortunately I don't think anyone got video.

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Well, when my buddy and I were BASEing and taking tandem vids, we used the long, VHS labels from the tandem videos. Since we were in a windy place with high humidity, and all of that irrelivant paranoid stuff, it worked well.

Didn't have a lineover there at least. Try it, you'll never, ever have a lineover again. Smirk.
Gravity Research Institute

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Why do we trap the inside c & d lines?

It seems like if something was going to get around the nose it would be one of the outside lines.

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Why do we trap the inside c & d lines?



It keeps the other (tail) lines centered relative to the pack job. If you didn't get the center D lines, the control line bundle might wander left or right.

You get the center C lines because they are the center D lines anyway (the two are cascaded together and are one line below the cascade).
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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