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I am duplicating this post from the "freepacking into skydiving rig" thread.

I would love to start a discussion about this. I believe it is a very important topic that the majority of BASE jumpers have either forgotten, or never been taught. I especially encourage those who disagree with my point to respond and explain why they believe a properly configured Deep Brake Setting is no longer required for slider down deployment.


No. You are correct. A properly set DBS used slider up will result in a deployment stall.

If your DBS can be used slider up, then it is probably too shallow to be truly considered a "deep" brake setting at your exit weight, and you ought to customize a true "deep" brake setting for yourself.

Here is yet another copy of something I re-posted a while back:


I believe that the BASE world is somehow forgetting that a Deep Brake Setting ought to be customized to a particular jumper. Partly this is a sign of laziness on our part. Partly, it is a bad habit being actively encouraged by some gear manufacturers (BR? Care to comment on why you are doing this?) In either case, it is certain to result in object strikes and injuries (see the wall strike at the last turkey boogie, under a shallow braked canopy).

I don`t understand what you are saying. There are two loops on control lines. The lower one (the one nearer to hands) is for slider up and the upper one (more near the canopy) is for slider down and they both brake your canopy at the same (your speed is same). The difference between both loops is constant for given canopy. So if you have properly set brakes for slider down than also your slider up setting is ok. I think this is common knowledge.
Is this wrong or am I missing something?

This is a very common misconception.

The appropriate deep brake setting for any specific jumper and gear combination is specific to that jumper and gear combination. So, if my DBS is set properly for me, and I give it to you to jump, it is no longer a proper DBS.

The two loops on the lines set by the manufacturer (or one, in the case of some manufacturers) are really just rough guesses, on the part of the manufacturer, at what an appropriate brake setting would be, slider up and slider down, for the "average" exit weight for that canopy. In fact, factory brakes are usually very shallow (i.e. a canopy deployed in factory brake settings will exhibit significant forward drive prior to releaseing the brakes).

Every jumper ought to set their own personal deep brake setting (and shallow, too, but deep is more critical because slider down openings are almost always closer to the object).

If you are using the "deep" brake setting that came with your canopy, it isn't really your "deep" setting. Some manufacturers do try to customize your deep setting based on your body weight (generally, leaving the shallow setting the same for every canopy delivered, but altering the deep setting by the customer's reported weight). While this is a step in the right direction, I strongly believe that it is the responsibility of every jumper to find their own deep brake setting, customized for their exit weight and gear configuration.

Note that some experienced jumpers actually choose to have three (or even more) brake settings, for varying configurations and conditions.

I think you misunderstood me. I also think that brakes should be customized. My question is why is the upper loop called deep brake setting and the lower one shallow? I still think they both brake the canopy the same. The difference only comes from control lines passing through the slider (on slider up jump) and making an angle and thus needing slightly longer lines for the same brake.

A few discussions that relate to this one (either directly or peripherally):

Emphasis added by me on all quotes.

Australian BASE Association Forum, discussion on 5th Control Line


Short BLiNC discussion about the effects of greater or lesser exit weight on a specific brake setting.



"Why Use Shallow Brake Setting" on BLiNC.


The bottom line is that what's deep for one jumper and gear configuration is not deep for a different jumper and/or configuration. Deep Brake Settings should be customized by each jumper for their own exit weight and jumping style.

If it were the same it would be hard to flare a canopy right,more you pull down more deep break you get=closer to your stall point under a flying canopy.If you open your canopy whith the deep brake on a sliderup it will give you a stall,but if you use the shallow setting on a slider off,then you get a slower opening.

I think just because we need names to differentiate between them, and that's what everyone calls them.


Absolutely. I think the names "deep" and "shallow" derive from their relation to each other if used in the same slider configuration. Regardless, they are just names. You could just as easily call them "1" and "2", except that then you'd have to explain what you meant to other jumpers who you wanted to discuss them with.

Sorry for the confusion. I don't think that you (or anyone else in particular) don't understand that brake settings need to be customized.

I've just had to explain this to six or seven new jumpers quite recently. In general, I've seen young jumpers assuming that the brake settings on their canopy would somehow magically be the correct ones for their body weight.

Good thread. I believe that the stock brake settings from the BASE manufacturers are set for the "lightest" jumpers, rather than the average jumper out there. When testing my new canopies for the proper DBS, I have always found them to be "way off".

To add or modify a DBS setting, you can mark the location and send it off to the manufacturer. Or you can purchase some FIDS and matching brake line and install yourself.

Another thing to look out for is the location of the toggles on the brake lines. Some jumpers will adjust this for slider off jumps, essentially making a shorter brake line.

edit: updated w/ "lightest" jumper.

You see lots of discuission about configuring DBS... the one that seems to be the most common being the halfway point between stall and shallow.

The problem is, proper DBS thus depends on a correct shallow setting, and I haven't seen much discussion of that.

What's the standard for setting a shallow brake setting?

Wow. Really? I've never heard that before. My DBS tends to be "just above stall". This gives me a great DBS for solid objects, but doesn't work so good in tailwinds (slider down towers and bridges), so I usually end up with a second "not so deep" brake setting for tailwinds.

I tend to set my DBS first, then set my shallow setting off the deep. Then I test the shallow setting out of a plane, so that a deployment stall won't hurt. My goal is to end up with at least a "maximum deep" setting for no-wind slider down, and a "terminal deep" (i.e. shallow) setting for terminal.

I tend to use the interval that the manufacturer set between their two settings as my "standard" to start looking for the shallow setting. In other words, if the manufacturers two settings are four inches apart, I find my deep brake setting and then put the "shallow" setting in four inches above it (for starters--then I test jump it). Of course, with BR now including only one setting, this technique won't work.

This may sound like a whole lot of work, and I do generally end up with four ( ) brake settings (maximum deep, "not so deep", terminal, and slider up subterminal). I'd rather put the work in on a new canopy, rather than just end up jumping a brake setting that gives me too much forward speed on opening.

The "halfway-point" method is in DBS document in CR's library. I might have to dig around a bit but I thought I saw something similar in a thread on Blinc.

Ah. Here it is.

The relevant part (emphasis added):


Interesting. I always use the "find the stall point then back off a little" technique, followed by a bunch of test jumps. I'd guess that my method will find a deeper setting, and the CR method will find a more conservative setting. Their setting will probably be usable in a tailwind, though, which my deepest setting usually isn't.

I totaly agree with Tom on this one. My deep brakes on my Fox will open at almost a stand still with no tailwind. I won't jump my deep brakes on antennas where there is almost always a tailwind.
Also, when I had the fifth brake line mod done on one of my Foxes it changed everything as far as the brakes are concerned. (FOR ME) It might not for others. Depending on your wing loading.

While awaiting the arrival of a new BlackJack 280, I've been reading a lot about setting the DBS. Since most of my jumps will be slider off with delays of 1 to 2 secs, this is obviously very important.

I wanted to ask, if you have black lines, how do you mark the area to insert a new loop?

You can do it with a white crayon, of the kind that tailors use to mark black clothing for alteration.

On the subject on DBS or settings being too shallow. Just wanted opinion on something.

I beleive that having the break setting to shallow is also detrimental in getting the canopy inflated, pressurised and flying quicker. If the setting is too shallow then the canopy will try and fly forward and thus bring the nose down and forward, this then shuts of a clean airflow to the nose.

Generally speaking would you say this to be true?

I think it's too difficult to generalize. If you have (for example) no brake setting at all then, yes, I'd generally agree.

But (especially with an unvented canopy) slightly shallower brakes can give you a marginally faster opening, because a little opening surge can help push air into the nose of the canopy.

I think it's going to be very particular to the type of canopy, exactly how "shallow" the brakes are, and presence/absence of bottom skin inlets.

My opinion- The number 1 or deepest brake setting was removed from the Fox and then the FLiK because after Vtec was fitted, using the number 1 brake setting for slider down jumps would result in the canopy surging backwards on opening. The shallower or number 2 brake setting became the preferred setting for slider down jumps. I have witnessed this many times and experienced it myself when I had my first Fox retrofitted. I have Video footage from above of a jumper doing his first BASE jump recently from a bridge using a borrowed Fox, using the number 1 or deepest brake setting the canopy surges backwards on opening. I don’t know of any objects where this would be considered a good thing. I know a jumper with 300 jumps on a Vtec Fox with the single factory brake setting and it works fine for him.

What I do- When I receive a new canopy I jump the factory setting for at least 20 jumps to ascertain weather I think it is too deep, shallow or spot on. If the factory setting was way off the mark then I would change it immediately but it has been a quite a few years since I have seen a factory brake setting that far off. I then add 2 more settings 4 inches apart. If I think the setting is spot on I will add a shallower and deeper setting. If I think the setting is too shallow I will add 2 deeper settings. If I think the setting is too deep I will add 2 shallower settings. When the opportunity arises I try the different settings to confirm I am using the optimum brake setting. The most important thing is then to log all your jumps noting delay and brake setting used. I number the brake settings starting with number 1 being closest to the toggle and 3 closest to the canopy. If your canopy has 5 upper control lines or has a steep angle of attack (such as a Mojo) then 2 inches between brake settings (instead of 4) may be required. Without you going through this process it is unreasonable to expect a manufacturer to provide you with a range of brake settings and an accurate description of how each will respond to openings for various delays.

Where you have your brake settings can be very personal. I believe we generally should all try and achieve the same thing, minimal forward speed on opening while losing the least amount of height. Using the stall point as the deep brake setting will result in minimal forward speed (and possibly surging backwards) but result in non-ideal height loss and a canopy that is slow to respond to riser input. A brake setting shallower than the ideal deep brake setting will result in losing minimal height but not enough to justify the extra forward speed. If you find this balance the resulting brake setting should enable the best possible response to rear riser input. The most important thing is to understand where your brake setting is, why, and what it means for you on opening.

On slider up sub terminal jumps, in order to achieve the same forward speed on opening, I will often use a brake setting 4 inches deeper than what I use for slider down jumps. To say I am using a deeper setting is not quite true as both jumps were made using the deep brake setting for the given delay and configuration.

In my experience with jumping low objects the effect of the brake setting on canopy pressurization is irrelevant. When selecting a brake setting it becomes more important to consider the glide and canopy control achieved in the first 3 seconds after pressurization.

Jason Fitz-Herbert

Interesting...

I've had personal experience with a canopy opening in stall on a slider-up BASE jump. The slider stayed at the base of the canopy until I released the brakes and started pumping. It's not an experience that I look forward to repeating.

That said, I use the factory setting for all slider up jumps. I have 3 deep brake settings available for slider down/off jumps. The deepest was set 3-4 inches below the stall point I found on a skydive, with a known exit weight, around 3000ft above sea level. The two additional settings are each 3-4 inches shallower than the prior DBS and are used at higher elevations and/or higher exit weights due to cameras or other gear.

Edit: I just had my standard FOX retrofitted with vents, valves and the 5th steering line over the winter, so I'll be experimenting once again...

My .02

Mark

Sorry it should read that the brake setting closest to the toggle is the shallower setting. Sorry for any confusion it may cause.

Jason Fitz-Herbert