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 kuba
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Hi All, was wondering if anyone can help with the problem I have. I'm trying to do 2 linked turns dragging my hip on the snow at each turn. The trouble is at the apex of the first turn my hip is still above the snow and if I want to carry on and put it on the surface I'll need some more time and as a consequence lose the turn continuity because I'm going uphill. Eventually I'm on the snow but can't continue my turns. Here's the pic explaining what I mean. On the left you can see an ideal situation where at the apex one has the hip on snow. On the right- more or less what I'm doing.

hip drop

I had 2 initial thoughts how to fix that: 1) make a bigger radius turn, so I'd have more time to let the hip go down- however this very often decrease the turn dynamics and I'm going too slow to lean inside the turn, 2) ski on a steeper terrain so I can make bigger radius and have more time- this one is hard for my legs; I don't have enough strength to handle pure carved turn on black runs. I've also attached pics with my stance at the apex (1.png) and when I'm going uphill (2.png)- they are from 2 different runs but you'll have an idea.

1
2

Would be great to hear suggestions/thoughts on that. Cheers.


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(@adrian_hamilton)
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My feeling Kuba is that because you have made the hip getting to the floor your intention then the turn is somewhat contrived rather than the intention to ski a speed and radius that creates the forces necessary for your hip to be low, making the hip position the outcome rather than the intention.

I know you're a good skier and you know my feelings on the subject. I hope a few others throw their ideas out on this one.

A video would be really helpful.


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 kuba
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@adrian_hamilton that's true, I'm trying to do this on purpose- it's not a result of proper skiing. When we spoke last time about River Radamus I googled his name and found this:

It's pretty amazing what he does . Thanks for your feedback:)


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(@adrian_hamilton)
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He certainly creates big big angles. He hasn't quite made the impact on the WC circuit that some might haver expected but his time will come for sure. Don't forget he is skiing at speeds that would make most of us soil our pants and he is tightening the arc to such a degree that the forces are huge. This necessitates the hip position. It's an outcome.

 


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(@geepers)
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@kuba

This increase in turn performance is something I've been working towards for the last couple of years. The 1st thing I learnt was that we cannot go directly at the end point (hip on snow) as this leads to all sorts of problems with hip dumping and generally being inside. Rather it has to result from increased carving performance.

Last Canada winter I had exactly that issue you describe - the turn progressing nicely, could get inside further but there's not enough arc of the turn left and it's time to turn the other way. There's a vid in another thread that shows where I was up to in March.

Then watched a number of vids by Tom Gellie, most specifically on the topic of toppling.  Tom's key point here is that to transition into a new turn we need to allow ourselves to topple at the top of the turn. This requires a measure of lateral instability for the body to continue to move inside the new turn. Angulation, however, tends to restore lateral stability as it moves the CoM slightly higher and to the outside. Some angulation is required for grip (platform angle) but too much too early is not helpful. Angulation is required to increase as the turn progresses especially below the fall line. 

(If you are into CSIA skiing then the new Physics of Skiing manual very much backs up what Tom is saying.)

Here's a vid of skinerd carving.

So comparing my carving to skinerd's I notice:

1. I use up a most of the range of my available angulation at the top of the turn. I am balanced over the outside ski early but blocking further movement inside the turn.

2. I am not maintaining separation and angulation on exit of the turn which means there's less lateral instability to work with anyway.

Tom Gellie advocates learning to balance against centripetal forces before confusing the issue too much with large amounts of angulation. His point is the body will angulate soon enough as we are quite good at not falling over. 

Now the toppling can take place at a leisurely pace (say as per Warren Jobbitt's turns below) or very quickly (as per Paul Lorenz's also below).

I elected to go for the quick method largely because that over-use of angulation at the top of the turn has a big component of self-preservation as toppling is scary and I'm not young. I figured if the transition happened quickly enough my body wouldn't have time to react. I also paid attention to maintaining separation and angulation into the transition.

Overall I was very happy with the way things felt. (Feeling can be deceiving so I'll reserve judgement until I see vid.) In Canada in March the CSIA L4 was suggesting increasing angulation later in the turn via the cue of keeping the shoulders level. Whilst this was an improvement it was hard work. It felt strained. In Australia in August the quick transitions resulted in more inclination and better alignment to balance against the centripetal forces. Increasing the angulation below the fall line became very easy, like relaxing into a comfy armchair. Versus the perched on the edge of a chair on a cliff feeling back in March.

The couple of pieces of objective evidence I have for improvement is that I had a couple of favorable comments from ski buddies about laying it over and I found I could carve slightly steeper pitches than previously. There's still a way to go to get consistency and not yet got hip to snow. That's not the goal. If it happens so be it - it will be an outcome of increased performance. And at some point I'm going to have to go back and learn to override my balance instincts at the top of turn to allow that slower toppling. 

Of course this has been my own journey and you may be at a completely different point with different issues. Let us know how it goes. 


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(@skinerd)
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@kuba You’ve got some awesome angulation going on there... 1mm to go!

If you can get some video it would be more helpful to determine exactly what needs to happen as still photos don’t usually tell the whole story.

However, from a physics perspective to get your hip on the snow you’ll either need more speed or a tighter turn shape. Of course the caveat is when you tighten the turn shape you often lose speed.

It’s easiest to get your hip on the snow going across the hill because that’s typically where the most force has built up and the slope itself increases the edge angle (which tightens the radius increasing force further)... plus the ground is closer to your butt.

My guess is you just need to build a little more momentum before you try to get your hip on the snow. It’s pretty hard to do until you’re a few turns in. If it happens that late in the arc, the act of getting your hip on the snow probably slows your momentum enough to make it impossible to achieve in the next arc.

Timing of the moves is the other key to maximizing your momentum. This is where some video would come in handy.


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 kuba
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@geepers, that sound like my journey. Can you post the link to a vid from March, please? I can't find it.

@skinerd

Posted by: @skinerd

Of course the caveat is when you tighten the turn shape you often lose speed

Can you elaborate more on that? To me it's the opposite, when I do a bigger radius turn I'm not bending the outside ski, so I can't really lean inside the turn.

Posted by: @skinerd

It’s pretty hard to do until you’re a few turns in

Yes, I need to switch from my banana turn hip drop to linked turns where I'll try to get closer to the snow.

As for the vids I only have these two:


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(@skinerd)
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@kuba yes, it’s a tough balancing act. The trick is finding enough centrifugal force to balance against. The two main ingredients required are speed and turn shape.

More speed = more centrifugal force

Tighter turn shape = more centrifugal force

That said, you’ll typically see far more inclination in GS compared to slalom even though it’s a much tighter arc because the speed is so much greater... and speed has a significantly greater effect on the forces.

You clearly have the physical ability to create a lot of angulation so I suspect the main issue here is loss of momentum. Based on the short video clip, it looks like you’re hanging on to that angulation for a long time and as a result you end up with an arc that traverses across the hill.

It would be nice to see some video with turns linked together as timing and intensity of the pressure in the arc and the transition will effect how much momentum you are able to preserve from one arc to the next.

I suggest linking several turns together before trying to drop your hip so far inside to give you time to build momentum. Sticking with a tight arc but trying to release it sooner to preserve this momentum. Try to build the pressure progressively by tightening the arc slightly just before you release it... and then release it before you lose the energy from it.

The analogy I often use is like pumping on a swing. It feels kind of like that but it takes time to build up. You can’t expect to be swinging level with the bar on the very first pump. 

This post was modified 2 weeks ago by SkiNerd

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 kuba
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@skinerd

Posted by: @skinerd

That said, you’ll typically see far more inclination in GS compared to slalom even though it’s a much tighter arc because the speed is so much greater... and speed has a significantly greater effect on the forces.

Interesting point. Big distances between the gates let skiers to get very low with their hips as they have more time, I think.

Posted by: @skinerd

It would be nice to see some video with turns linked together as timing and intensity of the pressure in the arc and the transition will effect how much momentum you are able to preserve from one arc to the next.

It will probably be useless as it's a gopro recording:

(I'm in the process of googling and gathering info on cams with good optical zoom as recording with gopro is pain- not enough details)

Posted by: @skinerd

I suggest linking several turns together before trying to drop your hip so far inside to give you time to build momentum. Sticking with a tight arc but trying to release it sooner to preserve this momentum

I'll start trying that on my next session, cheers!


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(@geepers)
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Posted by: @kuba

that sound like my journey. Can you post the link to a vid from March, please? I can't find it.

Vid in this post Plenty of room for improvement!

As skinerd says got to generate enough centripetal force. Varies with the square of the speed and the inverse of the turn radius. (F = m*v2/r)

There's a relevant graph in a CSIA Physics In Skiing Manual on how required inclination varies with speed and turn radius. For a 25 degree ski slope (which is an intermediate run) the inclinations at various speeds and turn radii are:

1. At 5 m/sec 10 degrees for a 16m turn and 15 degree for a 10m turn

2. At 10 m/sec 35 degrees and 49 degrees for the respective turns

3. At 15 m/sec 58 degrees and 69 degrees respectively.

So a big increase in angles with speed, less so with turn radius.


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(@adrian_hamilton)
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@kuba I thought this might be interesting for you. 

free skiing carving for fun - Reilly McGlashan - YouTube


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 kuba
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@adrian_hamilton wow. Just wow. This snow is quite choppy and he's still able to hold his hip on the snow. Cheers for the link!


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(@adrian_hamilton)
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@kuba He’s such a great skier. I think sometimes the videos of these guys doesn’t really show just how fast they ski.


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(@geepers)
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Hi Adrian, I was also going to post it in this thread for @kuba - you beat me to it.

Those guys do ski fast and the vid doesn't fully capture that speed. Also generally hard to tell the steepness of the pitch from vid. It all looks about the same!

Was hoping that it was a recent skiing and that he's back in the game with his amazing skiing. From comments under the vid it turns out it's from a few years ago.

This post was modified 1 week ago by gpatters

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 kuba
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@geepers cheers. They do move fast- the point is that when filming from the bottom of the hill the camera's zoom can't capture the speed. Similarly when someone follows them with a cam.
As for the steepness, I'd be curious to see these slopes they ski- I think every skier has this perfect gradient when she/he can achieve the best turns and it's very personal.


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