Forums: Skydiving: Safety and Training:
NOT releasing brakes in an emergency?

 


GLIDEANGLE  (D 30292)

Oct 8, 2012, 3:32 PM
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NOT releasing brakes in an emergency? Can't Post

As I have thought about incidents with various jumper injuries which impair their ability to flare fully with both arms, it occurs to me that it MIGHT be prudent to leave the brakes stowed for flight and landing in these incidents.

Turns could be made by using rear risers (perhaps even a 270 degree turn the wrong direction to go the right direction if turning toward the incapacitated arm is too hard).

Landing would be without flare... just a PLF with brakes stowed.

The type of canopy and wing loading certainly would influence this decision. A big, slow student canopy might land acceptably with no input and the brakes stowed. A heavily loaded high performance canopy might NOT land acceptably in the same manner.

Jumper upper body strength would probably play a role too... If strong, a single arm flare might be easy; if not strong, a single arm flare might be impossible.

I am NOT advocating this as the correct solution I am seeking a discussion of folks views of the pros and cons of this tactic.

Thanks!


yoink

Oct 8, 2012, 4:03 PM
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Re: [GLIDEANGLE] NOT releasing brakes in an emergency? [In reply to] Can't Post

I'd say it's entirely dependent upon the size and type of canopy, and the familiarity the jumper has with flaring one-handed.

If you're not used to it (or don't have altitude or time to practice) it can be easy to accidently induce a turn when flaring with both toggles in one hand - you naturally pull slightly to the side. If you're jumping a large, docile canopy this turning impact may well be worse than just leaving everything stowed and taking a PLF.

The twitchier a copy is, the worse this problem will be...

On the other hand, if you're under a canopy that comes out of the sky like a rocket with a steep glide, there's a decent chance it'll break you if you don't try and level out some. That's why we recommend canopy experience and drills before people get onto HP canopies - People on them have enough experience to weigh up this entire conversation in a couple of seconds (as everything is going wrong) before rationally deciding on a course of action, and have the ability to carry it through.

If you find yourself in this situation when you're on a tiny, highly loaded canopy, and you're injured to the point that you're trying procedures for the first time as you're going along without the experience to guide your judgements, well, you put yourself in that position you dumb bastard! Laugh.. my sympathy for that sort has person has gradually eroded over the years!


davelepka  (D 21448)

Oct 8, 2012, 4:55 PM
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Re: [GLIDEANGLE] NOT releasing brakes in an emergency? [In reply to] Can't Post

 
As previously mentioned, there are many variables that come into play when making that type of call, and it really depends on the overall situation.

That said, there may be times where a no-input, brakes-set landing might be the best option available, and it should be in the list of possible courses of action.

One thing I will say for a jumper with a dislocated shoulder or broken arm (really any situation where they only have one arm available), if they do choose to unstow the brakes to fly and land the canopy, always unstow the brake opposite your good arm first. This way, if it turns out you cannot reach or unstow it, you're not spiraling to your death with the other brake already unstowed. You're more likely to be able to reach the brake on the same side as your good arm, and also more likely to be able to slove a 'problem' on that side should one arise. If you blow the brake on your 'good side', and then find you cannot reach the other one, you've just made way more problems than you already have.

Another point along the same lines, if you are trying to flare and land with one arm, don't be hung up on the idea of a 'full' flare. You'll have more control and better leverage on the toggles with a half or 3/4 braked landing, and this should be more than enough to allow a PLF to offer you an injury free landing. Pulling the toggles down to right in front of your face/neck will give you more control and better allow you to protect yourself on the landing/PLF. Trying to get the toggles all the way down and remain centered might prove to be diffucult, and introduce some 'turn' to your 'flare'.


wmw999  (D 6296)

Oct 8, 2012, 5:56 PM
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Re: [davelepka] NOT releasing brakes in an emergency? [In reply to] Can't Post

Before we go too far down this line, remember that if you decide late to unstow your brakes after all, you might also end up with one toggle stuck and the other one not, or something else like htat.

I.e. your decision altitude for this should be high enough that you can cut away (damaged whatever and all) and deploy your reserve still. A decision altitude is a decision altitude.

Wendy P.


AggieDave  (D License)

Oct 8, 2012, 6:02 PM
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Re: [wmw999] NOT releasing brakes in an emergency? [In reply to] Can't Post

In reply to:
Before we go too far down this line, remember that if you decide late to unstow your brakes after all, you might also end up with one toggle stuck and the other one not, or something else like htat.

I.e. your decision altitude for this should be high enough that you can cut away (damaged whatever and all) and deploy your reserve still. A decision altitude is a decision altitude.

Wendy P.

This is important.

I gave this sort of scenario a lot of thought in the past few years, with a main loaded at 2.75 something as simple as unstowing the brakes feels like you shifted gears and cracked the throttle wide open on a top fuel dragster.

I had no qualms about landing with a broken toggle and flying completely on my rears on that heavily loaded Velo, but having a disabled arm would probably of resulted in a chop to my much more forgiving reserve. Sure there is no guarantee that the reserve would work, but burning in at full flight on a Velo loaded that high would have resulted with significant injury (even with a solid PLF).


5.samadhi

Oct 8, 2012, 8:41 PM
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Re: [AggieDave] NOT releasing brakes in an emergency? [In reply to] Can't Post

dave, interesting comment...thanks for the food for thought.

at what Wingloading would your decision making tree begin to change?


fcajump  (D 15598)

Oct 9, 2012, 6:39 AM
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Re: [GLIDEANGLE] NOT releasing brakes in an emergency? [In reply to] Can't Post

Agreed that it is definately something to consider. I would suggest there are several items to think about here...

Arm incapacitation - If you are likely to ONLY have a problem with one arm, then... how practiced are you on flying this canopy one-handed. how survivable will the landing be if you try it with brakes still stowed. how about if you flare one handed and don't do it right (or fully)?

Additional incapacitation? - Is the cause (or result) of what ever messed up your arm likely to affect your head too? Were you hit in the arm and head by another jumper? Is the pain/blood/etc in the arm going to overload your adrenalin and incapacitate your ability to do what needs to be done?

NOW how do you think about landing your main?
Is your reserve any better?
Is it worth the added risk of cut-a-way and reserve deployment to get a bigger/docile canopy?
Is the stress of one-handed cutaway and another opening shock going to cause additional incapacitation?

Finally - remember if you choose to unstowe one-handed, you are very unlikely to be able to undo that choice... I doubt you can restow them one-handed if you decide that you're not up to it.

Preparation for this:
1. practice (up high, in clear air) flying/flaring your canopy one handed. May teach you how to, might convice you its a bad idea.

2. practice (up high, clear air) flying with brakes stowed, especially if you think this is what you'd choose to do. While I would suggest seeing how your canopy flares this way too... (of other reasons) that won't help you in your one-handed, brakes stowed landing...

3. Get a reserve that has a good chance of a survivable landing if you are incapacitated. (This normally has the added benefit of being a more agreeable one-handed or brakes stowed or tight out or unconcious condition canopy.)

4. Maybe even get a more docile main canopy for those jumps when you are with lots of people, or newbies or specialty jumps.

Just my $.20 worth
JW


SethInMI  (A 47765)

Oct 9, 2012, 11:51 AM
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Re: [5.samadhi] NOT releasing brakes in an emergency? [In reply to] Can't Post

In reply to:
dave, interesting comment...thanks for the food for thought.

at what Wingloading would your decision making tree begin to change?

If you have a digital altimeter that can show descent rate, you can get an idea what you are up against by checking the rate under stowed brakes.

This formula d = v^2 / (2a) would allow you to calculate the equivalent height to practice jumping off to hit the ground with the equivalent speed, where a is 32 fps^2 or 9.8m/s^2.

That means landing under a 20fps descent rate is the same as jumping off something 6.25 ft high, and a 15fps descent rate is the same as jumping off something 3.5 ft high.


skyjumpenfool  (Student)

Oct 9, 2012, 1:14 PM
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Re: [SethInMI] NOT releasing brakes in an emergency? [In reply to] Can't Post

In reply to:
In reply to:
dave, interesting comment...thanks for the food for thought.

at what Wingloading would your decision making tree begin to change?

If you have a digital altimeter that can show descent rate, you can get an idea what you are up against by checking the rate under stowed brakes.

This formula d = v^2 / (2a) would allow you to calculate the equivalent height to practice jumping off to hit the ground with the equivalent speed, where a is 32 fps^2 or 9.8m/s^2.

That means landing under a 20fps descent rate is the same as jumping off something 6.25 ft high, and a 15fps descent rate is the same as jumping off something 3.5 ft high.

Do you have a cheat sheet for this formula? I'd like to keep it in the pocket of my jumpsuit with a calculator.... just in case. Sly

You know, the reserve is there for a reason. Use it.

The bad arm dilema is interesting though? With a bad arm, do you (1) improve the situation by cutting away and (2) can you cut away? Unsure


SethInMI  (A 47765)

Oct 9, 2012, 2:58 PM
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Re: [skyjumpenfool] NOT releasing brakes in an emergency? [In reply to] Can't Post

In reply to:
Do you have a cheat sheet for this formula? I'd like to keep it in the pocket of my jumpsuit with a calculator.... just in case. Sly

I know you are just joking, but I case I was not clear, I am saying it would be a good exercise to find out the brakes stowed descent rate on one of your next jumps, then go through the trouble of calculating and practicing PLFs trying to work up to a height that gave you an equivalent landing impact.

Practicing flaring and flying with one hand would be excellent too, especially if your practice PLFs convinced you landing your canopy stowed was going to break parts of you.


AggieDave  (D License)

Oct 9, 2012, 5:57 PM
Post #11 of 15 (2570 views)
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Re: [5.samadhi] NOT releasing brakes in an emergency? [In reply to] Can't Post

In reply to:
dave, interesting comment...thanks for the food for thought.

at what Wingloading would your decision making tree begin to change?

For me it was when I started getting north of 2.0:1. It will be different for different people on different canopies and wingloadings.

For instance, I had a 1 rotation rule. If I had linetwists that started to spin, I would give it a single full rotation to arrest the spin. Beyond that I would chop it before the G-loading built.


rockola  (E 2631)

Oct 11, 2012, 6:24 AM
Post #12 of 15 (2328 views)
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Re: [GLIDEANGLE] NOT releasing brakes in an emergency? [In reply to] Can't Post

In reply to:
Turns could be made by using rear risers (perhaps even a 270 degree turn the wrong direction to go the right direction if turning toward the incapacitated arm is too hard). (...) A big, slow student canopy might land acceptably with no input and the brakes stowed.
I've landed a big, slow 270sqft student canopy on rear risers, brakes unstowed. It was hard bordering on impossible to steer, it was so heavy. I don't think I could have managed a 270 deg turn in a reasonable amount of time. I imagine leaving the brakes stowed would not make it any easier to steer.


skyjumpenfool  (Student)

Oct 11, 2012, 9:18 AM
Post #13 of 15 (2280 views)
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Re: [rockola] NOT releasing brakes in an emergency? [In reply to] Can't Post

In reply to:
In reply to:
Turns could be made by using rear risers (perhaps even a 270 degree turn the wrong direction to go the right direction if turning toward the incapacitated arm is too hard). (...) A big, slow student canopy might land acceptably with no input and the brakes stowed.
I've landed a big, slow 270sqft student canopy on rear risers, brakes unstowed. It was hard bordering on impossible to steer, it was so heavy. I don't think I could have managed a 270 deg turn in a reasonable amount of time. I imagine leaving the brakes stowed would not make it any easier to steer.


All these "what ifs"???? Back in the 70's, while in a hurry to catch a load, I hooked a canopy up backwards (Standard Cloud). Having plenty of time to play and do control checks, I decided to land it backwards. I got one of the softest landings every...... I also scared the shit out of myself the last 300 feet.

My "new" personal policy is to chop any and all shit! My reserve is my friend. Wink


wmw999  (D 6296)

Oct 11, 2012, 4:22 PM
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Re: [skyjumpenfool] NOT releasing brakes in an emergency? [In reply to] Can't Post

I did exactly yhe same thing with a Viking about the same time, except it was a cross-country. Stood it up close to the hangar.

Wendy P.


Periapt  (D 3017)

Oct 13, 2012, 3:28 PM
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Re: [fcajump] NOT releasing brakes in an emergency? [In reply to] Can't Post

In reply to:
...
3. Get a reserve that has a good chance of a survivable landing if you are incapacitated. (This normally has the added benefit of being a more agreeable one-handed or brakes stowed or tight out or unconcious condition canopy.)

4. Maybe even get a more docile main canopy for those jumps when you are with lots of people, or newbies or specialty jumps.

#3 is one of the soundest pieces of advice re. reserve canopies I have seen. I know there are those who want the smallest, lightest rigs possible, but to assume that you will always be fully functional and able make a perfect landing in an emergency situation is folly. No reserve can guarantee you an injury-free landing, but being prepared for the worst case scenario by having generous safety margins seems eminently sensible.

Also, #4 seems worthwhile advice, unless you are truely invincible and immortal.



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