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Just wondering if most jumpers take the time to fine tune their brake settings or just go with the factory settings. Do you use different settings for slider up and down/off jumps?

since you have only 2 posts, I'm not sure this is the best question. adjusting brake settings permits a jumper to customize their rig, but is it required?

do you have a single rig, or multiple ones?

do you specialize in terminal walls, or low stuff? (neither requires varying the rigging.)

how is your parachute performing? does it have too much speed on opening? is it in a stall?

what kind of objects are you jumping? (some or more sensitive to settings than others.)

do you have a friendly object (like the potato bridge) that facilitates fine tuning (good for video and is very forgiving)?

I sense this is a theoretical question, rather than a practical one. do you have something that's broke, needing fixed?

I'm a newbe. I have 8 jumps off one easy object. Been borrowing gear so far. I'm just curious to see how many jumpers fine tune their gear. Wondering what the mindset is among most jumpers. Do most canopies have 2 settings?
Thanx for the reply. Seems hard to get replies around here...

1, 2 or 3 brake settings would be dependent on the canopy, range of objects and packing configs and personal prefs.
As for personal preferences, I'll give you an example.
300ft solid object with no overhang.
No slider config. Same canopy and W/L.
Jumper A prefers a shallow brake setting and a not so vigorous launch.
Jumper B prefers a deep brake setting and a vigorous launch.
Take care,
space

cool. thanx for your input!

in BASE, so much is about personal preference. there is a lot that CAN go into it.

at least one BASE instructor offered to help set DBS (deep brake settings) during their course, if the student owned a rig.

I bet most students, however, just borrow rigs from the instructors. you have 8 jumps on borrowed gear. choose the right objects, and it is not a problem.

(sadly, jumpers have created major headaches by relatively simply packing errors. recently, someone crossed their toggles and struck a cliff! anxious beginners might be better off with easy objects and single brake settings. hopefully, they can stow them correctly...)

In my opinion, your two polls have the same answer.

On a solid, slider down object, pack the canopy in proper (i.e. tuned to the jumper's body weight) deep brakes and avoid imminent object strike on risers.

Note that this will cost you a lot of altitude (because you are stalling half the wing). Therefore, you should only turn on risers the minimum amount necessary to avoid object strike (never more than 90 degrees unless your object selection is pretty absurd), then switch to toggles (to pull the canopy out of the stalled flight mode and start trying to conserve altitude to set up a good landing).


On everything else (either slider up or non-solid objects), pack the canopy in factory shallow brakes and correct off-headings on toggles.


What do most people do, though? That's a totally separate question. In my experience, most jumpers in the USA are packing in factory deep brakes (not customized to their body weight) for all slider down jumps, and factory shallow brakes for all slider up jumps.


Why set deep brakes at all? The manufacturer of your canopy has probably just set a good conservative (i.e. lots of room for lighter jumpers not to stall at deployment) brake setting assuming a wingloading around .75. By tuning the DBS to your body weight, you minimize the amount of forward speed at opening.

My definition of a "well tuned" DBS is: the brake setting which gives the minimum amount of forward speed at opening while still giving a stall-turn response to hard riser input. If the canopy is moving forward as it turns in response to hard riser input, then the brake setting is probably too shallow. If the canopy waffles and stalls, falling straight down without turning, in response to hard riser input, then the brake setting is probably too deep. With properly set deep brakes, a hard riser input prior to clearing the toggles will stall half the wing, causing it to slide backward, while the other half creeps forward (with minimal speed, as the brakes are still set), resulting in an overall flight path that turns while slightly backing up, and at the same time results in a major altitude loss.

The goal of tuning DBS is to give the jumper the maximum reaction time prior to object strike in the event of a serious off-heading from a solid, slider down object. This is achieved by giving the minimum canopy forward speed with the brakes set.


I'd also recommend that you read over this document on deep brakes from the Consolidated Rigging web site. The following paragraph is fairly on-point to your question.



As with all things BASE, there is no "answer" to your question. The voice of God has not spoken from on high to give us the 11th Commandment, instructing us when to use Deep Brakes and how to set them. Every jumper will have their own opinion. Your job is to gather as much information as you can and make a decision that you are comfortable with, because it is your own safety that is at risk.

I am confused. I thought that a heavier jumper would be more likely to stall the wing given that a heavier loaded canopy requires less toggle stroke to induce a stall. I have experienced this first hand as I have a f-111 PD 190 that I was overloading at 225lb without gear. It would routinely stall on opening and when I first got it I could only flare to chest level before stalling the wing. Once I took out all the slack in the brake lines I could flare to my waste, but unless I was swooping it I had to be careful not to stall it. It seems counter intuitive to me that a lighter jumper would risk stall on a canopy in DBS.

Great info Tom. It makes a lot more sense to me now. Thanks!

Heavier jumper = higher wingloading.

Higher wingloading = faster flying canopy.

Faster flying canopy = needs more toggle input (or deeper brake setting) to slow down to same speed.


A canopy will stall when it's airspeed falls below it's stall speed (which is different for every canopy). A canopy with a lower wingloading (i.e. lighter jumper) will reach that airspeed sooner in the control stroke because it will have a lower airspeed to begin with.

Ever heard Robi's saying about "gravity is our engine"? The same thing applies to canopy flight. Higher wingloading means a "bigger" engine (i.e. faster flying canopy).



It sounds to me like the problem there is that the toggles were set too short. The toggle setting and the brake setting are two totally independent things. If memory serves, you are pretty tall and thin for your weight, which probably means you have longer arms than the average person your weight. This means that you would need the toggles set longer than average (or that you will stall the canopy earlier in the control stroke). There are other ways to deal with this (for example, 4 upper control lines will give you a lot wider control stroke than if you have 5 on the canopy), but the simplest is just to lengthen the toggle setting (which may require replacing the lower control line with a longer one).



If you're up for experimenting at the DZ, put in some super-deep brake settings on your canopy and grab a big weight vest. Figure out what brake setting is almost at a deployment stall with the weights on, and then take them off and try again.

OK, I guess the next thing that I don't understand is that we are trying to slow the wing down to near stall speed on opening. If the jumper is heavier then the stall speed should be higher, negating the idea that he needs more toggle input to slow down.

Have you done any testing in this matter? I know you have done a lot of physical testing in various aspects of base.

I'm also confused, I've been told that stall is about the AoA and not the air speed, and that wing loading is a factor in the "creation" of lift for the wing. If you have a higher wing loading, you'll get less lift (might not be that true because our wings are not rigid and depends on cell pressure) and the stall AoA decreases, so you'll need less input to reach it. I might have misunderstood the concept but I think it's important to square this out.

EDIT: Oh wait, I read that again. While a heavier jumper needs a deeper break setting to get to the same slow speed as a lighter jumper with a shallower break setting, it puts him closer to the stall point.

When I take a canopy with brakes well tuned for a heavier jumper and put a lighter jumper under it, the canopy stalls at opening, then backsurges, then dives and recovers (as the jumper clears the toggles).

When I take a canopy with brakes well tuned for a lighter jumper and put a heavier jumper under it, the canopy surges forward at opening and does not stall.

When I tune the brakes for a specific jumper and then add weights to the jumper, the canopy moves forward faster at opening.

When I tune the brakes for a heavier jumper and then the jumper loses weight, I have seen the canopy stall at deployment.

Cool, good to know, just seems counter intuitive to me.