The first time I saw someone ski a steep & narrow shoot with fully
carved short radius turns, I thought his skis were waxed with Velcro. Joining the ranks of ski instruction, I often heard how this is impossible
. Knowing differently, I spent a lot of time trying to figure out how it could be done. While many posts above cover the idea pretty well, I’d like to add some of that infinitesimal detail I enjoy so much. Please pardon any uncredited overlap with prior posts.
I too agree that traveling at ‘high speed’ across a wide hill helps to establish Early-Edge Carving.
But what of narrow shoots and short radius turns?
First, consider that we don’t really need a high edge angle that early
in the turn - it’s supposed to be progressive anyway, right? So when turn transition is 90-degrees to a 30-degree slope we’d need a ski-tilt of maybe 35-degrees off horizontal (5-Deg engaged)? Sure, that would work - to start anyway.
Second, as the turn progresses toward the fall line (say 15-degrees further into the turn) deliberately holding that same ski-tilt angle off horizontal translates
into an effective
ski-tilt angle of 40-degrees relative to the current slope-surface underfoot. And this does not include any deliberately added increase.
Many past threads have described this ‘increased effective-edge angle’ as occurring late in the turn
where the increase can cause the ‘spiral-in’ effect that Prosper mentions above. We generally don’t notice that it also occurs early
in our turn - probably because we’re so busy noticing the falling-sensation and lack of weight (and therefore pressure) on our skis. Active extension of previously flexed legs at this point also renders it less noticeable.
Side thought: YOT mentions ‘reverse angulation’ above. Standing motionless on a 30-degree slope we
contort into a severely angulated position (dramatic use of knees) and balance over our engaged
downhill edges. OK, not for long. And it would be pretty precarious - but it could be done and without our whole upper body hanging out in open space at 35-degrees. The further out in space we’re willing to dangle, the less contortion we'd need. But then, we'd be falling over too.
Anyway Third, Digging out the Lateral-Foot-Thrust concept from the Ankle Power thread, consider the potential for laterally thrusting
our feet up the hill at moment of edge-change.
Since our upper body is way more massive than our ski-laden feet, our skis will be pressed into the hill for a bit - before our upper-body is driven out into space. From this subtle effort we gain another little bit of early-edge engagement - one that actually serves to bend our skis as well - even if they are only slightly angled away from flat. Extension of legs at this moment only increases the effect.
Fourth idea: The relevance of Speed. Turns out it’s not
our forward speed that counts - it’s the Ratio
of our Falling
speed to our Forward
speed (and rate-of-turn) that matters most. In particular, the speed at which our upper body (CM) is falling over (tipping) down the slope as it pivots laterally from our skis.Regardless
how fast we’re moving forward, a body tipped at any given angle sideways will always topple over at the same rate of acceleration when only gravity is to blame. Whether moving at five, or fifty mph forward - we topple sideways
at a rate determined by the angle (from vertical) our CM happens to be away from our ‘Base-of-Support’. I fuzzy-qualify ‘Base-of-Support’ because the precise point of pivot is a messy concept with two independent legs & feet involved…
The further past vertical we deliberately tilt into our new turn, the faster we will fall over - and the less time we have for our skis to generate a supporting centripetal force. I think this argues loudly against making an excessive diagonal movement. If you choose to ‘dive’ into your new turn your only recourse is to twist your skis to an edge.
What it boils down to is at transition we need our rate of lateral falling
to be less than our rate of direction change
We can improve the situation by completing our turns on steeps to just beyond
90-degrees - specifically to create a teeny bit of CM momentum up the hill
(or at least, directly across the hill) to assist our early-edge engagement efforts.
The importance of 'ratio' mentioned above is strictly true in all cases - just as it is in very short radius turns. If we can arc our skis through the entire turn quickly enough, the speed with which our skis come back “under” us is faster than our fall to the side can dump us on our ear - we catch ourselves.
I suspect most of us use bits & pieces of the components above but the most common technique is likely to be the launch & catch
method. As I've said before - it's all good. And great fun to experiment with.
PS: Hopefully, PhysicsMan has not bartered into any 'owed' assassinations lately. If I turn up missing...