Reliance on altimeters

[SimonBones 1]

Try this sometime as a way to train your eyes. Plan to sink it a bit low on your belly for a jump. Looks straight down at the ground but pay attention to what you pick up in your peripherals.

Somewhere between 2,000 and 2,500 you'll stop being able to see the horizon or sky in your peripherals and will only see Earth. This is usually why ground rush starts to kick in. It is a good visual cue to when you're getting low but it only works when you're looking straight down.

108 way head down world record!!!
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[leroydb 0]

for a long time I have not used an alti... I pull after the tandems pull and I shut my camera off

lately though I have wore my sunto...

Leroy


..I knew I was an unwanted baby when I saw my bath toys were a toaster and a radio...

[Andy9o8 0]

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Put me solidly in the "train your eyes" camp.

It's nice to know that the alti played such an important role in training my eyes in the first place and using it has it's benefits but when push comes to shov it's eyes that I depend on. All those gadgets are nice and they are tools to be used. IMHO, it's the eyes that are the most dependable.

In training your eyes, you should be training them in the realm of the "big picture" not on some specific feature at any one particular DZ.

If you've got time to glance at an alti, you have time to glance at the ground.

Me, too. It would never occur to me not to use my eyes to help gauge altitude during a jump. Maybe it's because I learned on the S/L progression method, where we started at 2,500 & then worked our way up to longer delays, 1,000 ft at a time. That helps to dial-in what each approximate altitude "looks like".

On the ride up, I sometimes amuse myself by looking out the window, estimating the altitude, then checking it against my altimeter. I'm usually pretty close.

When I'm doing RW, especially when we're linked and just holding our last stable formation, I sometimes zone a bit and get sloppy with checking my altimeter. But I always have the ground in sight, and that gives me the visual reminder, "Hey, check alti."

[kallend 1,623]

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Try this sometime as a way to train your eyes. Plan to sink it a bit low on your belly for a jump. Looks straight down at the ground but pay attention to what you pick up in your peripherals.

Somewhere between 2,000 and 2,500 you'll stop being able to see the horizon or sky in your peripherals and will only see Earth. This is usually why ground rush starts to kick in. It is a good visual cue to when you're getting low but it only works when you're looking straight down.

My eyes are fine, thank you. Don't know why this was a response to me

...

The only sure way to survive a canopy collision is not to have one.

[SimonBones 1]

I just hit reply on the last post to mine. It wasn't intended to be a response at you specifically.

I guess I need a lesson on forum ethics!

108 way head down world record!!!
http://www.simonbones.com
Hit me up on Facebook

[Fast 0]

I have to agree with everyone who is saying to use your eyes. I have jumped without altimeters before. Mostly when other people forget to bring them or they have a problem on the plane. I don't need one. It makes me more comfortable if I do have one. I am not dependent on my audible mostly because I don't always remember to turn it on in the morning. That, as stupid as it sounds, has kept me from becoming reliant on it.

We even have a skydiver at my dz that doesn't own an altimeter. He sold it back in the 70s for jump tickets and never bought another one, even after over 10,000 jumps.

I am much more trusting of my eyes. If I can't see the ground because of clouds and I have lost altitude awareness its time to pull. I can also in that situation typically have a good idea based on how long we have been skydiving if I am at a "safe" pull altitude. I have made the mistake of waiting to come out of the bottom of them to pull before because I knew what the "base" was. It moved down about a 1000 feet and I didn't end up pulling till 2000.

Altimeters are great but in most cases your eyes are much more reliable for judging between "keep skydiving" and "time to pull" altitudes.

~D
Where troubles melt like lemon drops Away above the chimney tops That's where you'll find me.
Swooping is taking one last poke at the bear before escaping it's cave - davelepka

[ASTKU 1]

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After all what is it? It's a clock

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I was always under the impression that an altimeter was a barometer.

I don't think you read all of this thread. He was talking about accidentally jumping with the on the ground training altimeters that IS a timer...

[repcool 2]

My personal choice is to use an altimeter, both a wrist and chest mount (Neptune and alti), and 2 audibles of different make. I switch the batteries out at every repack. I don't expect everyone else to do the same.

As a pilot I was taught to trust my instruments. I certainly agree that eyes and internal clocks are all part of the instrument panel we have access to, so I use ALL of them, and it the readings from a couple don't add up I will just go ahead and pull. I wouldn't be comfortable doing anything more than a hop n' pop without an altimeter. I don't need to train my eyes for anything more detailed because they won't ever be my one and only instrument. I do continue to train my eyes for altitude under canopy, which is when they become primary.

I recently started to wingsuit and my internal clock instrument started to tell me it was pull time, but both my eyes and altimeter said otherwise, I was at 8k. I can't see what harm having access to that information does. I also did a HALO where I felt the urge to pull at 18k even though the ground still looked like another planet!

You can dog on me if you please, but I know my comfort zone and I happen to like gadgets.

[billvon 2,400]

>Honestly though, how many jumpers check the ground during
>their skydives other than during the track, and the spot?

How many drivers check the status of the traffic light as they're pulling up to it? Are there really that many drivers who stare at the light and ignore the road?

Nope. Most drivers look at what they are doing (i.e. what's in front of them) and note the color of the light in their peripheral vision. The ground takes up a lot more peripheral vision than a traffic light does; it's not hard to include it in your awareness.

[billvon 2,400]

>As a pilot I was taught to trust my instruments.

But if you have any instrument training (which is the one time you absolutely need them) then you also have training in how to fly with one or more of them inoperative. And if you fly VFR, I suspect you were trained to keep your eyes primarily out the windscreen rather than on the panel.

Indeed, a lesson from aviation is instructive here. It is now understood that any important non-functioning instrument must be clearly labeled "INOPERATIVE" (preferably by covering it, or by flags/indicators if it fails due to loss of signal or something) because if you trust a non-working instrument it can rapidly lead to loss of situational awareness.

Unfortunately, most altimeters in skydiving have no such indication. Visual altimeters either go blank or stop moving, which at least you can determine after looking at them a few times. Audibles have no such warnings.

> I don't need to train my eyes for anything more detailed because
>they won't ever be my one and only instrument.

I hope you could safely land an aircraft at night after losing electrical power. (In VFR of course.)

> I can't see what harm having access to that information does.

Nothing at all. It's suddenly losing the information that causes the problem. Visual altimeters aren't too bad in this way since you can see that they're not working. (i.e. it's been 8000 feet for 10 seconds now.) Audibles are more dangerous since there is no warning that they have failed.

[repcool 2]

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>As a pilot I was taught to trust my instruments.

But if you have any instrument training (which is the one time you absolutely need them) then you also have training in how to fly with one or more of them inoperative. And if you fly VFR, I suspect you were trained to keep your eyes primarily out the windscreen rather than on the panel.

Indeed, a lesson from aviation is instructive here. It is now understood that any important non-functioning instrument must be clearly labeled "INOPERATIVE" (preferably by covering it, or by flags/indicators if it fails due to loss of signal or something) because if you trust a non-working instrument it can rapidly lead to loss of situational awareness.

Unfortunately, most altimeters in skydiving have no such indication. Visual altimeters either go blank or stop moving, which at least you can determine after looking at them a few times. Audibles have no such warnings.

> I don't need to train my eyes for anything more detailed because
>they won't ever be my one and only instrument.

I hope you could safely land an aircraft at night after losing electrical power. (In VFR of course.)

> I can't see what harm having access to that information does.

Nothing at all. It's suddenly losing the information that causes the problem. Visual altimeters aren't too bad in this way since you can see that they're not working. (i.e. it's been 8000 feet for 10 seconds now.) Audibles are more dangerous since there is no warning that they have failed.

The flying thing goes both ways, a VFR is using eyes as primary much of the time, but you had better know how to trust instruments when you need to do a 180 to get out of a cloud.

Anyway, I have my plan and I am sticking to it, it doesn't rule out eyes but it also doesn't rule out gizmos.

[Fast 0]

Not tryin to pick on anyone at all. The point I was trying to make is that, your eyes looking at the ground are the most reliable instrument you have provided you can see the ground and that at least in my case, I trust them above all else.

Jumping without an altimeter is just an advantage that I have cause I am willing to trust my eyes. (It lets me help out people in the plane who are unwilling to jump w/o one. That way they don't have to ride the plane down)

Blue Ones!

~D
Where troubles melt like lemon drops Away above the chimney tops That's where you'll find me.
Swooping is taking one last poke at the bear before escaping it's cave - davelepka

[repcool 2]

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Not tryin to pick on anyone at all. The point I was trying to make is that, your eyes looking at the ground are the most reliable instrument you have provided you can see the ground and that at least in my case, I trust them above all else.

Jumping without an altimeter is just an advantage that I have cause I am willing to trust my eyes. (It lets me help out people in the plane who are unwilling to jump w/o one. That way they don't have to ride the plane down)

Blue Ones!

I don't have any beef with that. Just out of interest, do you have to recalibrate your eyes if you go to a different DZ? Maybe desert instead of grass, of mountains in your vision instead of flat kind of thing?

[Piece 0]

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your eyes looking at the ground are the most reliable instrument you have

What makes you believe this? A quick glance at the fatality database shows that the overwhelming majority of skydiving incidents are caused by the failure of the gizmo located between the backpad and chest strap. For example, lots of people pound in after misjudging altitude during a swoop and that's much closer to the ground than breakoff. Admittedly, swooping is probably (I don't swoop) much more sensitive to mistakes.

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Jumping without an altimeter is just an advantage that I have cause I am willing to trust my eyes.

I agree with an earlier post that whether you use mechanical altimeters to back up your eyes or vice versa is mostly a moot point. But to have no back-up at all? What if you misjudge?

Anyway, how you determine altitude is your choice. You have 6 times my jumps so it's all good

http://icanhascheezburger.com/2008/02/28/funny-pictures-i-come-with-sarcasm/
Proudly uncool since 1982.

[mdrejhon 8]

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I immediately pulled and found myself in the saddle and under a fully functional main at 2500...

For a bigway jump event of a 50-way league, sometimes one has to let go of the hackey at 2500 just after having tracked away from the outers of a formation. Basically, at some of these events, I can't initiate the deployment procedures above 2500 feet. That means you're in the saddle just right around hard deck. One gets used to it though.

Other than that, I don't normally initiate deployment that low...

[mdrejhon 8]

This brings up a really good question.

I just got my first audible (flashing LED), partially for the purpose of improving awareness during bigway jumps. Now I notice it often goes off 1 to 2 seconds before the breakoff. So I often end up looking around and glancing at my altimeter, for a second (to doublecheck) then break off -- I'm still one of the first to breakoff now on a portion of recent jumps with the new audible.

Does this mean maybe I should turn off the breakoff altitude on my audible and only rely on the pull/flatline as alarms. That way, I am forced to rely only on my existing altitude awareness (ground, wrist, and other people breaking off --but trying to be the first one to waveoff after 4500 feet passes, for example)

And sometimes bigway jumps have conditinally-delayed breakoffs (a stable 50-way at 5500 feet is safer than a mess at 6000 feet), where I must wait for leg kicking...

I don't want to de-sensitize my altitude awareness because my audible notifies me a little bit quickly. Is it because the audible is inside my helmet instead of outside, or is it just normal -- that I notice the LED more quickly than many people notice their audibles?

One idea I may do is to set the audible to 4000 feet breakoff, even for 4500 feet breakoff dives. That way I'm forced to continue to depend on my existing awareness and I can more easily beat the audible without becoming unconsciously dependant on it for breakoffs, and if the 4000 feet breakoff triggers, it means everyone is a tad slow including myself and it's time for me to go ahead and do some indpendent breakoff action. (Please note -- the waveoff and turns seem to happen at about 4300 feet, but that could just be calibration differences. That way, 4000 ft alarm should only occur when I've finished turning and already starting tracking -- it would become a "you must have already started tracking by now!" alarm, rather than "start breakoff" alarm.). Does anyone use audibles this way? Opinion?

[repcool 2]

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One idea I may do is to set the audible to 4000 feet breakoff, even for 4500 feet breakoff dives. That way I'm forced to continue to depend on my existing awareness and I can more easily beat the audible without becoming unconsciously dependant on it for breakoffs, and if the 4000 feet breakoff triggers, it means everyone is a tad slow including myself and it's time for me to go ahead and do some indpendent breakoff action. (Please note -- the waveoff and turns seem to happen at about 4300 feet, but that could just be calibration differences. That way, 4000 ft alarm should only occur when I've finished turning and already starting tracking -- it would become a "you must have already started tracking by now!" alarm, rather than "start breakoff" alarm.). Does anyone use audibles this way? Opinion?

I like having mine go off early. If breakoff is 5000 I will set mine for 5500. I prefer to use it as a tool to prompt me to start the next part of the dive flow rather than command me to turn and burn! That means when it goes off I look around and use my altimeter, I don't just assume it is right. Between the 2 audibles that makes for a lot of beeping, which to me means "time to do something else".

The other week I noticed mine didn't beep at 1000 on the climb, I made note to see how it behaved on the way back down. It beeped and when I checked the other data points I was still way above break off. I recycled it on the ground and it didn't play up again, but I quickly purchased another model!

[billvon 2,400]

>I prefer to use it as a tool to prompt me to start the next part of the
> dive flow rather than command me to turn and burn!

Problem is that if it fails, you never get that warning to check your altimeter or start the next part of the dive flow - and you might just realize that at 500 feet. In general, it's better to be breaking off early and thinking "hmm, it didn't go off when it was supposed to" than be in freefall at 500 feet thinking "hmm, freefall seems longer than I'm used to."

One of the benefits of setting it below breakoff. I generally do that on bigways, so that if I get a warning I know it's _definitely_ time to go.

[repcool 2]

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>I prefer to use it as a tool to prompt me to start the next part of the
> dive flow rather than command me to turn and burn!

Problem is that if it fails, you never get that warning to check your altimeter or start the next part of the dive flow - and you might just realize that at 500 feet. In general, it's better to be breaking off early and thinking "hmm, it didn't go off when it was supposed to" than be in freefall at 500 feet thinking "hmm, freefall seems longer than I'm used to."

One of the benefits of setting it below breakoff. I generally do that on bigways, so that if I get a warning I know it's _definitely_ time to go.

As often happens when I speak up here I end up getting a decent perspective from the counter on it. I kind of like that idea and shall consider it.

I still haven't got an answer on adjusting eyes\sight picture when jumping at very different dz's?

edited to add eye question.

[JohnRich 4]

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I still haven't got an answer on adjusting eyes\sight picture when jumping at very different dz's?

Yes, differing terrain types can make a dramatic difference on your perception of your altitude. Flat featureless desert gives less clues than an area with large trees or hills. Likewise, if you switch to a place with a runway that's twice as long as what you're used to, that can lull you into thinking that you are higher than you really are, because the size as seen in freefall is different from your usual smaller runway.

We tend to tune our eyes for the terrain of our home drop zones, and we get used to that. But then when you travel to someplace different, beware, because the visual cues differ.

[mdrejhon 8]

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One of the benefits of setting it below breakoff. I generally do that on bigways, so that if I get a warning I know it's _definitely_ time to go.

At the last Perris P3, some people on my bigway turned and tracked too quickly on their audibles, rather than wait for the whole base to kick their legs as a breakoff signal. They were reminded that they should have waited for the leg kicking, even if it was a slightly lower altitude.

I have noticed bigways have a tendancy to have conditionally delayed breakoff signalling -- basically the organizer may bring the bigway 500 feet lower than usual if it's stable.

The 400-Way World Record attempts used this technique. Basically the breakoff altitude is set conservatively originally assuming a mess of a formation, and when the formation is stable, it's then typically reasonable to delay the breakoff very slightly down, up to a bottom end of range such as 500 feet lower. (i.e. 5000 feet instead of 5500 feet breakoff)

By setting my audible's breakoff to a lower altitude, I might be able to avoid becoming dependant on the audible and then ending up doing such actions.

On the other hand, because my audible seems to beep ever so slightly early, I am already seems to have sorta trained myself that when the audible goes off, it means "pay attention to breakoff", sometimes I wait until the instant I see the first person start to breakoff, then initiate my breakoff.

It's a tough call (good arguments both sides) but I can see it is likely safer for me during bigway events, to have a safety margin BEFORE or AFTER the breakoff rather than the EXACT breakoff, since that's inflexible in the light of flexible/variable breakoff initiation altitude used in bigways including World Record. Basically when the breakoff is commanded by leg kicking or another technique such as a center pull.

[happythoughts 0]

I use every piece of gear that I can.

The no-pull/low-pull category used to be a lot larger.

I check the cloud base on the way up.
In freefall, I look across the formation behind the others.
When I see clouds, or the trees are a certain size, it's time.

Second, I have an alti. I use it.

On big-ways, where the breakoff happens in waves, it is for the safety of others also. Plan the dive, dive the plan.

[Broke 0]

Don't forget that from one altimeter to the next in freefall can be 500 feet off of eachother

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[kallend 1,623]

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Don't forget that from one altimeter to the next in freefall can be 500 feet off of eachother

I had one that was very inaccurate. So I bought a better one. It checks against a IFR calibrated aircraft altimeter with less than 40' error all the way up to 15,000ft.

...

The only sure way to survive a canopy collision is not to have one.

[Broke 0]

Freefall accessories?

Divot your source for all things Hillbilly.
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SCR 14192