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I have been thinking of making a deep brake setting on my canopy, but if I do that I can't use the tailgate.
So should I make a new tailgateplacing further down the C-line?

Would having the tailgate further down change anything on the deployment?

let's start here... why can't you use a tailgate?

is it that it is now so deep the canopy itself is down over the tailgate setting spot?

Yes! (If I understand what you wrote there)

The current tailgateplacing matches the factory deep setting.
If I would make a "real" deep setting the tailgate would be too far up the C-line and not reaching the controllines.

gotcha!

hmm. i'm not sure, but i would think it would be no problem to move the TG anchor point down the C line to accomodate it.

I would say go to a forgiving span, use a conservative wrap of tape in the spot you are planning to put the new tailgate, and give her a test jump or two.

And because you-know-who is also weighing in on this, I'll add: if it doesn't work, it was body position. Body position.

The last step in installing a custom DBS is to move the tailgate to the new location. Leave the old install in as well, for times when you use the deeper factory setting.

The tailgate should be placed in the highest possible position that does not catch tail fabric in the tailgate bundle.

Using a tailgate that is too high is very difficult. Using one that is too low can encourage tailgate hangups.

Presumably, if he is installing a new custom DBS, he has already made repeated test jumps. I have a lot of experience doing it and it still takes me 5-10 jumps on most student's rigs.

Hellis, if you are just randomly placing a deeper setting into your line and expecting it to work as a custom DBS, I'd strongly advise against it. That's a good way to get the canopy backsurging at opening (and potentially striking the object tail first).

Old discussion on this topic...

I have not yet found the brake setting, but will do it next summer.

If forgiving span is a high span, then no. The spans around here will probably give me linestretch and no more if I static line it.

But I will test it from a airplane. That would work?

I will read the old thread when I get home from work, I didn't find it when I searched for it earlier. Thanks

My plan was too keep the factory tailgate position and add one for deeper brake setting.

I think that answerd all the questions

Testing it from an airplane will not be representative, for a couple reasons. First, you'll be deploying at much higher airspeeds from a plane, no matter how slowly you jump out (joke). Second, you should pack slider-up when jumping your BASE rig from a plane, and I don't believe you're trying to find a deeper slider-up brake configuration. Also, slider-up with the tailgate can be tricky/problematic.

I agree with keeping the factory tailgate position for shallow brakes. The higher the tailgate is on the lines, the better. There is more outward force available to open the tailgate as you get closer to the bottom skin of the canopy.

I don't need the tailgate to test deep brake setting, just the slider.

The brake setting won't matter (as much) until the canopy is inflates, and the tailgate usually does it's job before that.
sure there is that split second just as it opens perhaps.

But my plan was more to see how deep can I set them and still have some input left before it starts going backwards

Not really.

A custom DBS needs to be tested (among other things) on a slider down opening, which isn't really possible from an aircraft.

I attempted to dial in my DBS last time I was at the bridge, didn't make as many jumps as I'd have liked to. Seemed conservative at the bridge, got home and jumped a somewhat technical B with the new setting and opened in a stall/surge, landing near the base of it. DBS should either be left alone, or tuned correctly in my opinion, no half assing the setting.

I see your points, thanks all.

So I guess I have to plan next years holliday in TF then...

One a side note: I did some DBS analysis at
the bridge, then checked it out back home, and
noticed the 4,000 feet difference in field elevation.

This was several years & couple hundred BASE
jumps ago... but me and my friends' perction
was that I had a slight bit of forward speed in
Twin but the same wing, same jumper, etc.
back home in our thick swamp air had less
forward speed on opening.

That makes sense, thanks

Seems a little excessive to travel to TF every time you have to set your db. We have had no problems setting our db here in Finland without anything high to jump. If you go deeper step by step and reach the stall point a minor stall shouldn´t hurt you. Pop your brakes early enough.

The objective of setting DBS should _not_ be to get as close to the stall point as possible.

DBS reduce the forward travel rate in brakes below the parachutal rearward rate in stall, allowing the overall canopy flight path to move backward when one side of the canopy is in stall and the other is set in deep brakes.

It is both unnecessary and potentially dangerous to push too close to the stall point. If your canopy is too close to the stall point in DBS, riser input on one side will stall the entire canopy (because it increases drag on the other side), and you will not have riser control with the brakes set.

Note to add...If the DBS are pushing the limit on the canopy stalling, not only will any riser input stall it, really bad body position will cause it to stall also. And you may never get the canopy flying before you hit something.

"The objective of setting DBS should _not_ be to get as close to the stall point as possible"

I just wrote "IF you...bla bla..reach the stall point a minor stall shouldn´t hurt you" There´s nothing about the final goal. Maby I use the term stall wrongly. Dunno. Hard language this english one...