From: Bob Dow (windtalkposter@yahoo.com)
Subject: Rail Pressure and Overpowered Jibing
View this article only
Newsgroups: rec.windsurfing
Date: 2004-05-11 09:55:47 PST
Rail Pressure and Overpowered Jibing
------------------------------------
Introduction
------------
This is an update to a similar article I posted at
the end of the season 2 years ago.
The insights are all due to lessons from Jason Voss, a
Windsurfing Mag contributing editor and teaching pro
based in the California SF Bay area:
http://www.jrvwindsurfing.com . The comments are
based on experience with boards under 105 L.
It's the beginning of a new season and I wanted to
encourage people who are working on their jibes to focus
on what's happening underneath the carving foot.
Summary: Good Rail Pressure Comes From Good Posture
----------------------------------------------------
Proper rail pressure is vital in jibing. If you have
it, your board feels slick and turns quickly downwind.
All of a sudden the rig feels light and calls out to
you, "Flip me!". If you don't have it the board feels
sticky and sluggish as you turn downwind and the whole
enterprise becomes manual labor.
How do you get good rail pressure?
* Adopt proper posture on entry: Knees bent, hips in,
back straight, head up, front arm straight, back arm
sheeting in. Imagine you are trying to align all your
weight above the carving foot.
* Raise the front foot up onto the balls of the
foot or even the toes during the carve. Don't think
about it, just do it. Explanation later.
History
-------
Several years ago I started updating my boards, moving
from older stuff to current gear. All of a sudden I
wasn't carrying as much speed through my jibes, and in
overpowering conditions I was spending too much time in
the water. My jibes were erratic. I signed up for
some 1:1 lessons with Jason Voss. Jason sails right
behind you, yelling at you to straighten your back,
pull in your butt, etc. You can feel the changes
immediately.
Epiphany
--------
The epiphany occurred when Jason yelled "Head up!" just
as I was entering a tricky jibe for me, high speed over
1 foot washboard chop. As I raised my head the board
started to accelerate instead of slowing down. At the
5 o'clock point I had, no exaggeration, 2X the board
speed of previous attempts. I had gotten good rail
pressure.
How to get Proper Rail Pressure
-------------------------------
The nice thing about getting good rail pressure is that
it comes from proper posture and weight distribution.
You can get it from conscious effort:
1. Take the back foot out of the strap and place it on
rail. Try to point the back foot more forward than
perpendicular to the board. Have your weight centered
on the back foot, neither on the balls nor on the
heels, but centered.
2. Raise the front foot up onto the balls of the foot
or even the toes. This guarantees that all your weight
will be on the back foot. It feels weird,
but works. It also has the effect of freeing the
front foot from the strap so you can switch more easily
when the time comes.
3. Knees flexed comfortably, but not too deep.
4. Butt over the back foot.
5. Back and neck straight. Reference has been made in this
forum to "curtsy, not bow." That means just
dip the knees, no bend in the waist. Don't bow.
6. Front arm straight, back arm sheeted in. Mast pointed
towards the inside of the turn. You feel like you are
"over" the boom.
7. Keep your head up, pointed where you want to go.
Benefits of Proper Rail Pressure
--------------------------------
* The board feels slippery and accelerates quickly as you
jibe into a gust.
* The board is much less affected by chop. It's on a
steeper angle and slices through chop like butter. Watch
out for getting air off those swell backs that used to
slow you down.
* More board speed preserved means more margin for error
on sail flip and foot switch.
* More board speed preserved means fewer rounded up
endings and much less energy expended getting on a
plane again.
* Overpowered jibing becomes much easier.
Rail Pressure and Overpowered Jibing
------------------------------------
What happens to the sailor when he or she tries jibing
while overpowered without correct rail pressure? In an
overpowered jibe, board speed across the water is most
likely less than wind speed. Apparent wind builds up
quickly from behind as the downwind turn is initiated,
pulling the arms and body forward and trying to pry the
sail open. The board accelerates sluggishly. The
bottom of the board feels sticky. It feels unsafe to
resist the pull of the sail, and the sailor decommits,
letting the sail open up.
As the sail opens up it catches more wind from behind,
pulling the body forward, straightening out the carve,
and now sinking the front rail, slowing the board down
and thus increasing apparent wind from behind again.
Now the sailor is in a vicious circle which will end
with surrender or, in the limiting case, a spectacular
maneuver where the board stops suddenly but the rider
continues on through the air at 25 mph.
Overpowered Jibing with Correct Rail Pressure
---------------------------------------------
The sailor adopts the correct posture and begins to
turn downwind. He pays special attention to feet:
front heel lifted, and weight centered over back foot.
He rolls in gradually, ankles first, knees, then hips.
The board accelerates instantly. If it feels sticky,
odds are that weight is too far forward and he lifts
his head and rocks back a little, making sure his back
is straight. With a gradual initiation the board
accelerates so quickly that there is never a lot of
scary force from behind on the sail, which allows the
sailor to keep the sail sheeted in. He feels like he
is secure, comfortably sitting on top of the back foot
and waiting for the board to go fast enough downwind to
produce that nice feeling of neutrality in the sail
when he can flip/step or vice versa.
If there is a big gust during the carve, he holds his
posture, knowing that the board will accelerate quickly
and neutralize the gust.
It's very choppy but it doesn't feel like it. It's
fun. He switches, flattening the board quickly and
exits on a broad reach, with enough board speed that he
can get organized without experiencing heavy wind
forces on the rig. He hooks in and is soon back on a
beam reach.
A Few Words About "Commitment"
------------------------------
We are always told that to be successful at jibing in
overpowered conditions we must be "committed".
Here is the posture that I always adopted as the
"committed" posture: knees extremely bent, weight on
the balls of the feet, upper body curved, and head
forward.
Sound familiar? This posture is a recipe for burying
the carving rail and getting launched. Every bump you
hit will cause your body to compact further and throw
more weight forwards. The benefit is that in your
compact shape you are already prepared for your
upcoming flight over the front of your board.
In working with Jason this is the first time I have been
told, in any sport, "Don't bend your knees so much."
This is bound to be a controversial notion, but after
watching the best jibers under the toughest conditions
I'm convinced. You don't need anything like 90 degrees
of flex. This leads to a curved posture which will put
too much weight forward. Maybe I'm a slow learner, but
in the year 2004 I'm still getting used to how sensitive
modern shortboards are to forward weighting. My muscle
memory seems to be stuck in 1990 when boards had a lot
more volume up front.
Commitment 2004
---------------
Re-program your muscle memory for "commitment"
in overpowered conditions as follows:
The willingness to roll into the jibe gradually and
*maintain* erect posture, head up, all weight on the
carving rail, sheeted in, for the 1 to 2
seconds it takes to accelerate downwind and neutralize
the sail for the flip.
For me the first sign of de-committing is letting the
clew open up on entry. If anything, on entry you should
sweep the sail back over the tail of the board -- but
bring it right back because now everything is going to
happen so fast that it will soon be time to flip and
you don't want to get back-winded.
Conclusion
----------
Much excellent advice has been given in this forum
about jibing. This poster believes that concentrating
on rail pressure exclusively for a few weeks can pay
big benefits in preserving board speed and improving
overpowered jibing. Give it a try!
Bob Dow
Redwood City, CA