0
Hvance

Head Position in a Track

Recommended Posts

Recently, several instructors/coaches at my DZ were teaching me the body position for a flat track. Among other things, they said my chin should be in my chest. Well, as I read the article on tracking in the latest Parachutist, the authors specifically say not to put your chin to your chest, but rather to look forward.

Can you guys please elaborate on the best methods and the rationales behind them?
I wish Google Maps had an "Avoid Ghetto" routing option.

Share this post


Link to post
Share on other sites
I wish I could... I'm just here because I'm curious too though really. Thinking I'll watch this thread for a bit.

I just did my unsupervised jump where I didn't have any stability goals so decided to try tracking a little. I just did what I saw another student get instruction on, palms down, arms in and chest cupped and toes pointed... I'm pretty sure I was looking where I wanted to go so I had my head up.

There were a couple of times where it felt like I was nearly straight up and down, which as they say only feels that way but still, it seems like tucking the chin would be bad in that situation.
_______________________________________

Share this post


Link to post
Share on other sites
here is my suggestion, go do a few dives with your chin tucked, and a few with it up...what you will notice is that with it up you sink faster b/c the air spills out from your face easier....with it down you will get a little more lift...when trackng with a group of people you will have to adjust your body position slightly for every jump, so just feel it out
IHYD

Share this post


Link to post
Share on other sites
On group dives you don't have the luxury of locking your head in one position and keeping it there. If you do that, then you've got "tunnel vision", and you're being unsafe by not being aware of what is going on around you.

You need to be looking around constantly to keep track of other jumpers, below, above and beside you, to make sure that you're clear for opening.

Worry more about your body position, and keep looking around with your head.

Share this post


Link to post
Share on other sites
What are you trying to achieve? Both answers are right, given the right circumstances. Lowering your head will give you more lift, which should allow you to track further before reaching deployment altitude. That said, you should still be able to see where you are headed, which is forward and down. If lowering your head that much compromises this, then a little less may be a good idea.

On a group tracking dive, it's unlikely that you'll be in anything resembling a max track and you're head will likely be in a position more appropriate for seeing the rest of the group and for providing lift.

Share this post


Link to post
Share on other sites
oh sorry I just received mine in the mail. So can I ask you a question about tracking? I have been doing the last 10 to 12 solo tracking jumps most recently at my DZ. I have been rolling my shoulders forward as my instructor told me to do back when she taught me tracking. I 'feel' as if I have been getting more forward speed doing this...I can't suck in my gut because I don't have one, but sometimes I have been keeping my arms in around a 45 degree upward pitch (still straight) while still in a track to get my head oriented downward a bit to pick up speed. Is this just wrong...? I have been experimenting with my track to become more efficient but I haven't jumped with an experienced tracker to evaluate how bad my track sucks...I hope I explained it correctly. If I am clear as mud, I will elaborate more on it. Thanks

Share this post


Link to post
Share on other sites
Quote

Recently, several instructors/coaches at my DZ were teaching me the body position for a flat track. Among other things, they said my chin should be in my chest. Well, as I read the article on tracking in the latest Parachutist, the authors specifically say not to put your chin to your chest, but rather to look forward.

Can you guys please elaborate on the best methods and the rationales behind them?



Chim Tucked????You gotta be shitting me...how are you going to watch out for other jumpers with yoru chin tucked?:S

Share this post


Link to post
Share on other sites
Quote

but sometimes I have been keeping my arms in around a 45 degree upward pitch (still straight) while still in a track to get my head oriented downward a bit to pick up speed. Is this just wrong...?



That's a very subjective question. What is "wrong"? ;)

Moving your arms back behind you in an upward pitch is tending more towards a delta. Thinking of a good track and a good delta as two ends of a spectrum of possibilities. A delta may increase your airspeed, but it does so by more due to increasing your descent rate than anything else. A good track actually goes up relative to a stable belly to earth position and should produce much greater horizontal speed than a delta will. A delta is most useful in getting down to a formation that is below and in front of you. A track is what you want at break off to get away from everyone quickly while maintaining altitude. While tracking, your arms will give more lift when by your side or even slightly in front (below) of your body. They should also be near your body, but not right against it. I usually suggest about a hand span away from the hips/thighs as a rough guide, but you should try tracking with someone else and experiment with how various changes in your body position affect your track.

Share this post


Link to post
Share on other sites
Don't worry about generating lift in a track, you won't.
(start obligatory aerodynamic argument now)

Without wingsuits, we move through air deflection.

Try and get flat as possible, presenting as much surface area to the wind as you can. Straighten your legs completely.

Use your head to look where you are going.

Share this post


Link to post
Share on other sites
Ill jump on that argument. I think we do achieve lift in a Max Track. Nothing compaired to the performance achieved by an aircraft wing or a wingsuit but by improving our body position we can increase lift at points on our body. When I nail my track I think I can feel the lift bubble on the back of my neck, shoulders, top of my rig. Do Ski Jumpers make lift on there body position other than plank deflection? Now my answer to head position, each persons body, position, angles, will be different in the track so the exact position of the head will be different to achieve the max lift. A 4 way out of a 182, 180 and max it out. Jumping with a lot of others, look where your going. I say work on finding the max and keep it handy.

Share this post


Link to post
Share on other sites
i'D SAY YOU SHOULD KEEP YOUR HEAD ON A SWIVEL, AND KEEP YOUR BODY FREE.

it might be "academic" to take one position or the other, but you will find you fly better with more body movement.

Enjoy your track, and stay safe
scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

Share this post


Link to post
Share on other sites
Quote

i'D SAY YOU SHOULD KEEP YOUR HEAD ON A SWIVEL, AND KEEP YOUR BODY FREE.

it might be "academic" to take one position or the other, but you will find you fly better with more body movement.

Enjoy your track, and stay safe



That's good advice.
:)

Share this post


Link to post
Share on other sites
Quote

Don't worry about generating lift in a track, you won't.
(start obligatory aerodynamic argument now)



Yes. Let's ague semantics when the guy wants to know how to track well. :S

Lift doesn't mean I go up relative to the ground. However you want to explain it, a good track has a significantly slower descent rate than your best slowfall position. No matter what term you want to use to describe it, there is additional upward force being created by a good track when compared to other body positions and tweaking the position to give better forward speed somehow seems to also create slower descent rates. A flat body position does not give you a great track. It'll get you away, but you can do much better and in some circumstances, much better is what is expected. A really good track needs some de-arching through the body and shoulders.

Share this post


Link to post
Share on other sites

Considering his experience level, it's pointless for him to worry about de-arching his shoulders to generate non-existant lift when he might be having a hard time going in a straight line.
:S

I see it all the time. A student immediately assumes an aggressive track position like he sees in videos and flies in a giant circle. Great. You work your way up by finding the right body position for you and your current ability. Not copying what everyone else does. The most important criteria in a track is to go in a straight line and be aware of everyone else and your altitude.

You start simple and work your way up. That's how you learn.

Share this post


Link to post
Share on other sites
Quote

Quote

Don't worry about generating lift in a track, you won't.
(start obligatory aerodynamic argument now)



Yes. Let's ague semantics when the guy wants to know how to track well. :S

Lift doesn't mean I go up relative to the ground. However you want to explain it, a good track has a significantly slower descent rate than your best slowfall position. No matter what term you want to use to describe it, there is additional upward force being created by a good track when compared to other body positions and tweaking the position to give better forward speed somehow seems to also create slower descent rates. A flat body position does not give you a great track. It'll get you away, but you can do much better and in some circumstances, much better is what is expected. A really good track needs some de-arching through the body and shoulders.


I agree that de-arching and cupping your shoulders, straighten legs, arms close to your side, etc. are ingredients for a good track. However, I don't believe you are significantly decreasing your vertical descent rate.... nor are you "generating" a significant amount of "lift" of the Bernoulli persuasion..... maybe just a little because of your "angle of attack". You are increasing your "absolute" airspeed. Kinda like how a tacking sailboat can go faster than the wind. Or, like a downhill skier you are "sliding" down the hill when you are tracking and your increased airspeed is derived from the downward vector and the translational vector, but mostly from decreased cross-section in the direction of travel. That was all intuitive guessing on my part but my mind can be changed by looking at some numbers.... maybe from a recording altimeter like a Dytter or something.

Share this post


Link to post
Share on other sites
When I was an activer jumper I felt like Maxtracking (post breakoff) was one of my stronger skills. I have afterburners on my jumpsuit and I feel like they really gave me alot more speed and possibly lift, of course I would keep my chin tucked for awhile then locate the other 3 jumpers I was with. Near my last jumps I was having some heading control issues which may have been caused by a lazy foot so I concentrated on pointing my toes more and findig a point on the horizon to focus on also. It always seemed that after opening that I was very far from the others both horizontally and somewhat vertically.

Share this post


Link to post
Share on other sites
Quote

Quote

Quote

Don't worry about generating lift in a track, you won't.
(start obligatory aerodynamic argument now)



Yes. Let's ague semantics when the guy wants to know how to track well. :S

Lift doesn't mean I go up relative to the ground. However you want to explain it, a good track has a significantly slower descent rate than your best slowfall position. No matter what term you want to use to describe it, there is additional upward force being created by a good track when compared to other body positions and tweaking the position to give better forward speed somehow seems to also create slower descent rates. A flat body position does not give you a great track. It'll get you away, but you can do much better and in some circumstances, much better is what is expected. A really good track needs some de-arching through the body and shoulders.


I agree that de-arching and cupping your shoulders, straighten legs, arms close to your side, etc. are ingredients for a good track. However, I don't believe you are significantly decreasing your vertical descent rate.... nor are you "generating" a significant amount of "lift" of the Bernoulli persuasion......


It should be an offense to practice physics or engineering without a license.

Lift is DEFINED as the component of force perpendicular to the free-stream vector. If you are tracking, you must be generating lift.
...

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

Share this post


Link to post
Share on other sites
[reply...............I agree that de-arching and cupping your shoulders, straighten legs, arms close to your side, etc. are ingredients for a good track. However, I don't believe you are significantly decreasing your vertical descent rate.... nor are you "generating" a significant amount of "lift" of the Bernoulli persuasion......



It should be an offense to practice physics or engineering without a license.

Lift is DEFINED as the component of force perpendicular to the free-stream vector. If you are tracking, you must be generating lift.



Points I was trying to make:

1) Tracking does not "generate" a significant amount of lift.

2) A very insignificant amount of lift is generated by the differences in pressure above and below your body because of the (usually misapplied) "Bernoulli effect" by trying to shape your body into an airfoil.

3) A somewhat less insignificant (or more significant) amount of lift is generated by your body's angle of attack.

4) No matter how well you think you can track you are not making as much headway as you think you are compared to the altitude you are using up.

The point I was trying to make is that making your body rigid and tweaking your angle of attack has more effect than trying to assume an un-clean, low aspect ratio airplane wing shape.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

0