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tred

hard deck

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listening to the jump twenty six podcast they mentioned that if you have passed your hard deck with a mal that you should pull your reserve with out cutting away. my understanding was more along the lines of your hard deck being the decision to either cut away or ride the main down. I am sure there is not a black and white answer and it depends on the mal and I will bring it up to my instructor this weekend but was just curious to any opinions on that subject

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tred

listening to the jump twenty six podcast they mentioned that if you have passed your hard deck with a mal that you should pull your reserve with out cutting away. my understanding was more along the lines of your hard deck being the decision to either cut away or ride the main down. I am sure there is not a black and white answer and it depends on the mal and I will bring it up to my instructor this weekend but was just curious to any opinions on that subject



You are both right--depending on the mal. The difference is that you are describing "best practices," while the podcast is discussing what to do when you find yourself in a non-ideal situation. For example:

Do you have a broken brake line, but your canopy is still flying straight and properly, and you feel confident landing it on rears? Then go ahead and land that main, my friend -- you're too low to cutaway and wouldn't want to risk fouling up your (almost perfectly good) main with a reserve pull.

Do you have some kind of catastrophic malfunction (say, for the sake of argument, your main canopy has torn in half), but somehow accidentally missed your hard deck without cutting away yet? I cannot recommend enough that you pull your reserve, and do not "ride the main down" just because you passed your hard deck.

Obviously these are the far ends of the spectrum. What if you have 5 broken lines? What if you have tension knots? What if you have a torn cell but the canopy is holding together?

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What if you have 5 broken lines? What if you have tension knots? What if you have a torn cell but the canopy is holding together?

i guess if your below your hard deck with problems like these as a beginner you've already blown past the safety precuations to prevent this so you have to make some hard decisions and do the best you can with your situation

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Jump twenty six attempts to clear up the verbiage confusion, but it is certainly confusing, especially to a beginner who is learning the sport and the terminology.

To be clear, this is what we teach at my DZ:

Decision Altitude: where you decide to keep your canopy or not; as in quit monkeying around trying to fix a malfunction and cut away and deploy reserve. For students, this is 2500ft.

Do not cut away point: where you are too low to safely cut away and deploy a reserve and have enough time and altitude for reserve inflation. 1000 ft.

If you did not take action at your Decision Altitude and you're at that 1000 ft mark, do not cut away. Just deploy your reserve because something above your head is better than nothing (as in a cut away main and a reserve not yet inflated).

I have heard both these points referred to as a Hard Deck, which is totally confusing. Talk to your instructors for what makes sense for you and your DZ and equipment. Good job being heads up and asking these questions!

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"Hard deck" does seem to be a term without a clear definition. Neither it nor "decision altitude" or "decision height" are in the USPA SIM. (I don't know what terms the book does use.)

I've seen other hard deck threads where people have different personal uses of the term. One person might use decision altitude for where to cutaway at, while hard deck is reserved for a lower level, reserve pull but no cutaway.

One should at least have those two different concepts in mind, whatever names one uses

(For Canucks, CSPA PIM 1 doesn't define hard deck, and PIM 2A uses it in the simplistic way to define both the decision about whether one's main is good, and whether one should pull the reserve without a cutaway.)

As evan85 points out, there's a difference between one's preferred altitude and where one is actually at. It's kind of like "don't pull low, unless you are". It becomes "don't cutaway low, unless you are ...except if really low, then reserve pull without a cutaway".

One might like to make a cutaway decision by 2000' and stick to that as a minimum if one is fighting a mal and getting down towards that level. On the other hand, if you pull and snivel to 1800' before discovering a problem, then decision height is going to be right there in the next few seconds!

It is good to set up a mental image of general safety boundaries, but then if one has already broken one of one's preferred boundaries, one needs to know the absolute minimum boundaries one is willing to try to use.

So the terminology is confusing, especially to a newbie, and the actual boundaries to use can be confusing too. Newbies tend to be given simplified information because one doesn't have a good feel for all the nuances yet. Even as an experienced jumper it is hard to tell what one's reaction will be or should be in a really unusual situation at some really low altitude. Better try to avoid those situations in the first place!

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pchapman

"Hard deck" does seem to be a term without a clear definition. Neither it nor "decision altitude" or "decision height" are in the USPA SIM. (I don't know what terms the book does use.)



"predetermined altitude" in Section 5:

4: You should decide upon and take the appropriate actions by a predetermined altitude:
a. Students and A-license holders: 2,500 feet.
b. B-D license holders: 1,800 feet.

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tred

listening to the jump twenty six podcast they mentioned that if you have passed your hard deck with a mal that you should pull your reserve with out cutting away.

You shouldn't go below your hard deck without cutting away a malfunction and using your reserve.

I don't agree with the podcast. If you go below your hard deck (1800') with a malfunction and you're going to be seriously injured or killed if you ride it in, you need to get your reserve out. The most reliable way to deploy it is to first cut away.

I've seen cutaways done successfully, even if scarily, from below 1000'. Sucks to be that low but you were the one that screwed up and went thru the hard deck. But I will not fire my reserve into a malfunction just because I'm at 1700 or 1600'. That's one bad decision after another.

My lowest cutaway? About 1200'. Nice landing in someone's front yard.

How low is too low? I don't know, but the answer is not "anything less than 1800 feet."

This is all assuming that you pull reserve IMMEDIATELY after cutting away. All you people who talk about "needing time to get stable before pulling my reserve" are doing it wrong and are much more likely to bounce. Don't do it that way.

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You shouldn't go below your hard deck without cutting away a malfunction and using your reserve.

I don't agree with the podcast. If you go below your hard deck (1800') with a malfunction and you're going to be seriously injured or killed if you ride it in, you need to get your reserve out. The most reliable way to deploy it is to first cut away.

I've seen cutaways done successfully, even if scarily, from below 1000'. Sucks to be that low but you were the one that screwed up and went thru the hard deck. But I will not fire my reserve into a malfunction just because I'm at 1700 or 1600'. That's one bad decision after another.

My lowest cutaway? About 1200'. Nice landing in someone's front yard.

How low is too low? I don't know, but the answer is not "anything less than 1800 feet."


I haven't listened to the podcast, so if they do actually suggest this, then I agree with you.

But it seems to me that this is again a confusion of the terms of "hard deck" and "decision altitude."

The decision altitude is the altitude by which, if we have no landable canopy, we perform EPs. The SIM recommends (Section 5.1.E.4) that, for B, C, and D license holders, this altitude be no lower than 1800 feet.

So, by 1800 feet, if you have a malfunctioning canopy (as opposed to no canopy) that you cannot land, you should cut it away and deploy your reserve.

But there is another predetermined altitude known as the hard deck. This is the altitude at which cutting away is likely to do more harm than good, because you're cutting away whatever drag the malfunctioning canopy is giving you (thereby increasing your speed towards the earth), but not giving your reserve enough time to deploy, and thus, by cutting away, you're likely to impact the earth at an unsurvivable speed. In those situations, your best bet is to deploy the reserve without cutting away on the theory that: (a) maybe it deploys cleanly; or (b) at the very least, more fabric out is better than less fabric out.

Now, WHAT that hard deck should be I don't think there's a recommendation (I've commonly heard 1000 feet, and that's what my own hard deck is). And I do think there's room for debate about whether the hard deck should be lowered because of Skyhooks (probability of skyhook failing versus probability of unsurvivable impact when you fire a reserve into a malfunctioning main). There's potentially even room for debate about how rigidly we should stick to decision altitudes and hard decks (e.g., if I'm kicking out of my last line twist at 1800 feet, do I cut away, or finish kicking out? If I'm at 975 feet when I decide I can't land my canopy, do I cut away, or just fire the reserve?).

But I don't think anybody is suggesting hard decks of 1,800 feet. At least, I hope not.

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SIM Section 5-1
E. Equipment Emergencies
Partial Malfunction
3. At some point during descent under a partial malfunction, it becomes too low for a safe cut away and you must deploy the reserve without cutting away. (p104)

So the SIM doesn't have a specific recommendation. Think about what works for you and your experience level regarding:
1. Your actual response time to notice a malfunction, decide to cut away, and take that action.
2. Ability to safely land the reserve you are flying on that jump after it opens - taking into account where you deploy your reserve.

I.e. if you cut away at 1800ft and are under your reserve at, say 1100ft, are you confident that you can land yourself safely? Without injury or a whole bunch of good luck?

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The term"hard deck" has no universal meaning. It is a cutesy term used in the movie Top Gun and people think it makes them seem cool when they use the term. Please do not use the term at all. It has no meaning beyond the user's use of it.

I have heard the term used to define:
. The breakoff altitude
. The pitch/pack open altitude
. The decision altitude as it is correctly defined in the SIM
. The lowest altitude you should cut away after fighting
a mal main (1000 feet?)
. I have even heard it used to describe a low cloud ceiling.

Point is: It has no meaning.

Please ditch the use of this movie term altogether, as it
will be understood in many different ways. It doesn't make you look cool. It makes you look like you want to impress people. At it's worst, it will cause confusion and make you end up by describing what you really meant in the first place.

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dpreguy

The term"hard deck" has no universal meaning.

Point is: It has no meaning.

At it's worst, it will cause confusion and make you end up by describing what you really meant in the first place.

Hmmm, interesting position. I think I agree with you. The term we use with students is "decision altitude". After reading your post, I'll keep an ear out for slang encroaching into my lesson plan.

I think a point I should have made earlier is that when you go below your decision altitude with a bad canopy and you still haven't deployed your reserve, you've left "safety land" and are now in "survival land", a much harsher environment. Safe is behind you. You're now just trying to survive.

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Please ditch the use of this movie term altogether, as it
will be understood in many different ways. It doesn't make you look cool. It makes you look like you want to impress people.


Well, my desire to impress you aside, I do think it's useful to have a term for the altitude at which you will no longer cut away a malfunctioning main, but will just deploy the reserve. Further, I think it's useful to have a predetermined altitude in mind, and not just decide as you're plummeting towards the earth.

So, in my mind, my decision altitude is 1800 feet (with allowable variances). My hard deck (which I hope to never reach) is 1000 feet. If you don't like "hard deck", what term would you suggest to replace it?

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Sorry to get pushy about the term. We have these discussions and they always end up with the person just describing what they really mean. The SIM uses 'decision altitude', etc. Whatever works that cannot be misinterpreted or misunderstood is best.

I don't have a term for the 1000 foot decision. It is just that.

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While we're at it, what's the term for the altitude below which you would go straight for the reserve rather than your main (loss of altitude awareness, emergency exit from the airplane, etc.)? The actual altitude probably depends on how long your main takes to open and the maximum altitude at which your AAD may fire. I don't remember a specific recommendation for this in the SIM. What's your personal threshold?

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mxk

While we're at it, what's the term for the altitude below which you would go straight for the reserve rather than your main (loss of altitude awareness, emergency exit from the airplane, etc.)? The actual altitude probably depends on how long your main takes to open and the maximum altitude at which your AAD may fire. I don't remember a specific recommendation for this in the SIM. What's your personal threshold?



just to ad to the confusion: I have also heard this called the "hard deck"
as in "if there is an aircraft emergency what is your hard deck that you would go straight to reserve".
You can't be drunk all day if you don't start early!

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John Mitchell. I agree with you. At some point I won't be looking at the altimeter anyway. Will just be trying to get it done and survive.
(probably won't be looking at the ground either - that would just be a distraction and wouldn't lend to doing anything with my hands)

This is a good discussion. I kinda came off like a jerk. Sorry.

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dpreguy


This is a good discussion. I kinda came off like a jerk. Sorry.

I didn't think so. I think you had a great point about "hard deck" not being a defined skydiving term.

In my other career, we had strict phraseology rules; what to say, what not to say. I constantly monitor my skydiving instruction for ambiguities, confusing statements, etc. :)

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Regarding emergency exits or going straight to reserve:

If I know my altitude is above 3000' I will use my main.
If I don't know, (ie I don't know my specific location over the ground and might be over a hill) or if I'm below 3000' I would go straight to reserve.

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sammielu

Regarding emergency exits or going straight to reserve:

If I know my altitude is above 3000' I will use my main.
If I don't know, (ie I don't know my specific location over the ground and might be over a hill) or if I'm below 3000' I would go straight to reserve.



3000' seems excessive for this. Recall that the SIM only requires main pack opening by 2500' (for C/D license) on a standard skydive--plenty of folks open there and are fine with it.

"But evan85," you say, "what's wrong with using my reserve that high? Maybe I don't need to do it, but it's my call whether to spend that extra $70 on a reserve pack job!" Here's what's wrong: you are wasting a precious safety opportunity. What if your reserve has some kind of malfunction? There's no way to (quickly and easily) cut it away and go to your main -- but your main was literally designed to do exactly that and let you switch to your reserve. Even at maximum conservativeness, your main should always be your first option if you're high enough to be in the saddle with enough time to cutaway if necessary. 3000' should be plenty high for that, for most people.

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sammielu

Regarding emergency exits or going straight to reserve:

If I know my altitude is above 3000' I will use my main.
If I don't know, (ie I don't know my specific location over the ground and might be over a hill) or if I'm below 3000' I would go straight to reserve.

What's the lowest you've ever pulled your main?

One thing to remember, when exiting a plane in flight (even gliding with the engine out), it takes 10 seconds to fall the first 1000', then 5-6 seconds each 1000' thereafter.

Leaving a plane in flight at 2000' you have almost as much time until impact as you do being in freefall at 3000'. I've done emergency exits from as low as 1200' and was able to use my main on all of them. Caution, this was pre AAD days.

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