Tail Walk / Fin Riding Excerpt from article

Tail Walk / Fin Riding Excerpt from article

Post by RJ Associate » Mon, 14 Dec 1998 04:00:00


As many may recall there was a thread a while ago about when one is
going fast and get hits by a gust one can ride with the board floating
about 4-5 inches above the water.  A bunch doubted it and said that it
would lead to spin out, etc.  The scientists / engineers said it just
might be possible, and Ben K said he read it was called tail walking,
etc. Roger went into great detail about his experience.

Here are several excerpts from the most recent American Windsurfer
magazine (Volume 6, Issue 1, 1999) from an article written by Eddy
Patricelli (the US guy who threw the first forward loop in the
Atlantic):

"The board has not stopped accelerating.  I widen my grip focus more
intently on my path, and sit deeper into my harness.  Things feel
different at this speed... They even sound different...I stand more
upright, roll my front shoulder over the boom and put all of my weight
over the mast foot...  Downwind of me, a swell breaks, leaving in its
wake an icy flat trail.  I turn onto it and it's as if the board has
broken free.  There's no tension on my front thigh, no struggle to hold
the sail down, or keep my weight over the mastfoot.  Everything remains
eerily still, quiet and easy.  I'm going faster than I have ever gone.
(writes about a wicked crash on a BIG wave)... Another session - he is
on a 9.4 way over powered...  "The wind has not died, In fact, it's
building.  And thanks to Ken (Winner) I'm on a bigger sail than pro's
who outweigh me by 40 pounds.  Forget it.  Live in the now.  It's only
an hour so shut up and sail.  A puff hits, and the board starts
tailwalking.  After several seconds of trying to bring it down, it
becomes clear I am not riding the board, it is riding me.  When it does
finally throw me, I rise from the water expecting rodeo clowns to
emerge..."  It's really a great article, but the point was to excerpt
discussion about tail walking and the form he has when he is really
going fast.

This is pretty much what had been discussed in the posts by the people
who defended that the board does separate from the water w/o spin out in
certain conditions:  weight in the harness, somehow get most weight
through the mast foot, loose front leg, gust happens, board floats,
sailer puts major pressure down through the fin, and board is still
floating along in pretty decent trim.  In the case of the article, it
ended in wipe out, but in the other cases mentioned in posts, the board
keeps on going for a bit and then settles down.  

Being comparatively new to this sport, I was blown away when this
happened.  It felt really cool, but after two sessions of it happening,
my fin got dinged, I had to sand it down, and now when ever I push /
pump really hard laterally on the fin to get the board up to speed, the
fin spins out. I can't push nearly as hard as I could before, and as a
result I have not had this happen since.  Time for a new fin.

I guess speed sailers must have to deal with tail walk / tail float
often.  I wonder if it's something to be avoided because it is easy to
wipe out?  Does it mean it's time for a smaller fin?  Or is it the way
one holds the sail with too much cant?  I don't want to beat a dead
horse, but so much of the last thread was about why it can or can't
happen.  I'd like to learn more about it by some of those speed sailers.
Any comments by believers welcome.  I bought a GPS to figure out how
fast it takes for it to happen, but since that fin got dinged and since
it doesn't happen for me with B&J fins, no luck.  

Beam me up again please Scotty,

Rich

 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by Vaughan James Sander » Tue, 15 Dec 1998 04:00:00



Quote:
>As many may recall there was a thread a while ago about when one is
>going fast and get hits by a gust one can ride with the board floating
>about 4-5 inches above the water.  A bunch doubted it and said that it
>would lead to spin out, etc.  The scientists / engineers said it just
>might be possible, and Ben K said he read it was called tail walking,
>etc. Roger went into great detail about his experience.
>I guess speed sailers must have to deal with tail walk / tail float
>often.  I wonder if it's something to be avoided because it is easy to
>wipe out?  Does it mean it's time for a smaller fin?  Or is it the way
>one holds the sail with too much cant?  I don't want to beat a dead
>horse, but so much of the last thread was about why it can or can't
>happen.  I'd like to learn more about it by some of those speed sailers.
>Any comments by believers welcome.  I bought a GPS to figure out how
>fast it takes for it to happen, but since that fin got dinged and since
>it doesn't happen for me with B&J fins, no luck.  

>Beam me up again please Scotty,

>Rich

Rich a tail walk is caused by sheeting out and releasing the mast foot
pressure, usually when you are over powered and hit by a gust. One of
Dave White's sayings is "when in doubt sheet in".
As I recall Roger said, he was sailing deep 45/90 in flat water (broad
135dg in our money). I don't think he was referring to a tail walk as it
is not a problem on a flat speed course this broad. Tail walking usually
happens to me when I am loosing control in chop and sheet out to save
myself. It doesn't work, I have had some spectacular ones on my new
Roberts 25 recently.
Have you seen the Acroplans (spelling could be wrong) that the Russians
were working on in the cold war. These boats (planes) fly a couple of
feet clear of the water at a certain speed, on a cushion of air. I
wonder if fin riding is related to this. This time of year we have
thousand of geese in the Thames estuary, they come in from Canada and
Siberia for the winter. They like to fly close to the water. Often when
I am out sailing, a squadron in perfect V formation will be coming
straight at me, only a ft or so above the water. They use the V
formation to save energy, and must know that they can get more lift
close to the water.

Jamie

Jamie Sanders
Chalkwell Windsurfing Club
 http://freespace.***.net/ken.rosier/cwc.htm                        

--
Vaughan James Sanders

 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by RJ Associate » Wed, 16 Dec 1998 04:00:00

Jamie:

Does tail walk feel like a spin out?  I have felt something that I had
not felt before when the nose of the board wants to go a different
direction than the tail.  It did not feel like spin out because there
really wasn't much pressure on the fin.  I do not know how it happened,
maybe it was by sheeting out.  The board just goes sideways for a while
and then you wipe out.

I read that Dave White broke his leg? doing a back loop this fall.  Must
be a lot of weight coming down his board, a wonder the board didn't
crack first.

Rich

Rich

Quote:



> >As many may recall there was a thread a while ago about when one is
> >going fast and get hits by a gust one can ride with the board floating
> >about 4-5 inches above the water.  A bunch doubted it and said that it
> >would lead to spin out, etc.  The scientists / engineers said it just
> >might be possible, and Ben K said he read it was called tail walking,
> >etc. Roger went into great detail about his experience.

> >I guess speed sailers must have to deal with tail walk / tail float
> >often.  I wonder if it's something to be avoided because it is easy to
> >wipe out?  Does it mean it's time for a smaller fin?  Or is it the way
> >one holds the sail with too much cant?  I don't want to beat a dead
> >horse, but so much of the last thread was about why it can or can't
> >happen.  I'd like to learn more about it by some of those speed sailers.
> >Any comments by believers welcome.  I bought a GPS to figure out how
> >fast it takes for it to happen, but since that fin got dinged and since
> >it doesn't happen for me with B&J fins, no luck.

> >Beam me up again please Scotty,

> >Rich

> Rich a tail walk is caused by sheeting out and releasing the mast foot
> pressure, usually when you are over powered and hit by a gust. One of
> Dave White's sayings is "when in doubt sheet in".
> As I recall Roger said, he was sailing deep 45/90 in flat water (broad
> 135dg in our money). I don't think he was referring to a tail walk as it
> is not a problem on a flat speed course this broad. Tail walking usually
> happens to me when I am loosing control in chop and sheet out to save
> myself. It doesn't work, I have had some spectacular ones on my new
> Roberts 25 recently.
> Have you seen the Acroplans (spelling could be wrong) that the Russians
> were working on in the cold war. These boats (planes) fly a couple of
> feet clear of the water at a certain speed, on a cushion of air. I
> wonder if fin riding is related to this. This time of year we have
> thousand of geese in the Thames estuary, they come in from Canada and
> Siberia for the winter. They like to fly close to the water. Often when
> I am out sailing, a squadron in perfect V formation will be coming
> straight at me, only a ft or so above the water. They use the V
> formation to save energy, and must know that they can get more lift
> close to the water.

> Jamie

> Jamie Sanders
> Chalkwell Windsurfing Club
>  http://freespace.***.net/ken.rosier/cwc.htm

> --
> Vaughan James Sanders


 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by Robert Youda » Thu, 17 Dec 1998 04:00:00

The 'low-flying' effect you are talking about is called 'ground-effect'. It
is caused when a solid interface (ground or water) reflects the vortices
unavoidably created during lift generation by a wing, increasing lift and
reducing induced drag. It requires vortices such as those genrated by an
aircraft wing to work, although a smaller (secondary) effect due to the
'compression' of air between the 'wing' (or board) can occur at extremely
low altitudes, especially if part of the board is still touching the water.
This helps keep the board up, but does not reduce drag as with ground
effect. In fact, drag is increased. If mast-foot pressure is reduced and the
front of the board is allowed to rise, it is easy for the wind to get
between the board and water, lifting the board right out of the water.
Depending upon how much fin still remains in the water, you may or may not
lose it. If mfp isn't applied soon, the board can rear right up and go way
out of control in a real hurry!

Rob

--

Please remove "XXNOSPAMXX" before replying by e-mail

Quote:



>>As many may recall there was a thread a while ago about when one is
>>going fast and get hits by a gust one can ride with the board floating
>>about 4-5 inches above the water.  A bunch doubted it and said that it
>>would lead to spin out, etc.  The scientists / engineers said it just
>>might be possible, and Ben K said he read it was called tail walking,
>>etc. Roger went into great detail about his experience.

>>I guess speed sailers must have to deal with tail walk / tail float
>>often.  I wonder if it's something to be avoided because it is easy to
>>wipe out?  Does it mean it's time for a smaller fin?  Or is it the way
>>one holds the sail with too much cant?  I don't want to beat a dead
>>horse, but so much of the last thread was about why it can or can't
>>happen.  I'd like to learn more about it by some of those speed sailers.
>>Any comments by believers welcome.  I bought a GPS to figure out how
>>fast it takes for it to happen, but since that fin got dinged and since
>>it doesn't happen for me with B&J fins, no luck.

>>Beam me up again please Scotty,

>>Rich

>Rich a tail walk is caused by sheeting out and releasing the mast foot
>pressure, usually when you are over powered and hit by a gust. One of
>Dave White's sayings is "when in doubt sheet in".
>As I recall Roger said, he was sailing deep 45/90 in flat water (broad
>135dg in our money). I don't think he was referring to a tail walk as it
>is not a problem on a flat speed course this broad. Tail walking usually
>happens to me when I am loosing control in chop and sheet out to save
>myself. It doesn't work, I have had some spectacular ones on my new
>Roberts 25 recently.
>Have you seen the Acroplans (spelling could be wrong) that the Russians
>were working on in the cold war. These boats (planes) fly a couple of
>feet clear of the water at a certain speed, on a cushion of air. I
>wonder if fin riding is related to this. This time of year we have
>thousand of geese in the Thames estuary, they come in from Canada and
>Siberia for the winter. They like to fly close to the water. Often when
>I am out sailing, a squadron in perfect V formation will be coming
>straight at me, only a ft or so above the water. They use the V
>formation to save energy, and must know that they can get more lift
>close to the water.

>Jamie

>Jamie Sanders
>Chalkwell Windsurfing Club
> http://freespace.***.net/ken.rosier/cwc.htm

>--
>Vaughan James Sanders

 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by MY-1 » Thu, 17 Dec 1998 04:00:00

On the new super wide boards its something I have started to do
intentionally. To go upwind, the board is heeled over onto the leeward rail
and this exposes the windward side. The lift can be felt quite obviously in
the front foot. With a short flat section and a super large fin, this makes
for interesting riding (poor ankles, poor knees) but does feel fast.  I may
be imagining it but the width does seem to soften the ride somewhat over
chop too. Something 295x67x47 is probably a significant wing in itself,
like a 1.x
sq metre sail flying horizontally.

my-11

 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by Vaughan James Sander » Thu, 17 Dec 1998 04:00:00



Quote:
>Jamie:

>Does tail walk feel like a spin out?  I have felt something that I had
>not felt before when the nose of the board wants to go a different
>direction than the tail.  It did not feel like spin out because there
>really wasn't much pressure on the fin.  I do not know how it happened,
>maybe it was by sheeting out.  The board just goes sideways for a while
>and then you wipe out.

Rich sounds like your describing spinout. There are two types of
spinout. 1/ stall, this usually happens in marginal winds when you are
forcing a board upwind. If you push to *** the fin the angle of
attack gets to much and the flow detaches. As you are normally not going
that fast when this happens, you should be able to recover it quite
easily. 2/ air cavitation (which I think you are describing) this is
caused by air getting on to the fin and again detaching the flow. This
can be caused by air getting sucked down from the tail of the board.
Something getting caught on the fin, weed, paper etc. Or more common the
fin coming clear of the water and trapping air when it goes back in.
This one can be controlled with practice, try to keep your weight of the
fin, and on your front foot just as it enters the water, then you can
put your weight back on to it.
If you do spinout, by having your weight on the front foot you can catch
it, by pulling your back foot under you. If you have really lost it side
ways you have to be careful not to catch the leeward rail when trying to
recover.

Quote:

>I read that Dave White broke his leg? doing a back loop this fall.  Must
>be a lot of weight coming down his board, a wonder the board didn't
>crack first.
>Rich

Dave broke a bone in his foot at West Wittering on the south coast early
in October. But with the help of pain killers he was still able to do
nearly 42 knots at West Kirby soon after. One of Dave's party tricks is
to do a pirouette round the sail as he comes down the speed course.
Especially if there are any cameras about :-))
Dave is the F2 UK importer (Whiteboarders) so he is not short of a board
or two.

Jamie

Jamie Sanders
Chalkwell Windsurfing Club
 http://freespace.***.net/ken.rosier/cwc.htm                        
--
Vaughan James Sanders

 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by RJ Associate » Thu, 17 Dec 1998 04:00:00

It was on a 295 with a 38 cm fin.  I think the hard lateral pressure on
the back strap may "correct" the horizontal lift of the fin to being
more vertical.  Then somehow the pressure from the fin comes straight up
through the board.  I think that the larger size of the fin allows this
to happen at comparatively lower speeds than w/ a smaller fin.
Quote:

> On the new super wide boards its something I have started to do
> intentionally. To go upwind, the board is heeled over onto the leeward rail
> and this exposes the windward side. The lift can be felt quite obviously in
> the front foot. With a short flat section and a super large fin, this makes
> for interesting riding (poor ankles, poor knees) but does feel fast.  I may
> be imagining it but the width does seem to soften the ride somewhat over
> chop too. Something 295x67x47 is probably a significant wing in itself,
> like a 1.x
> sq metre sail flying horizontally.

> my-11

 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by RJ Associate » Thu, 17 Dec 1998 04:00:00

Jamie:

So what does the board want to do when it is tail walking?  I understand
how it happens (sheeting out at speed, loss of mfp), but do not know
what happens to the board before you go down.  

Dave White and Peter Hart seem to have a great time together in the
Fuerte video.  I guess he has a bit more "insulation" when compared to
many of the rest of us to let him sail at high speeds and do some of
that funny stuff.  Peter Hart seemed to like including the helmet shots
of White wiping out during his jibes at the end of the speed course.  It
took me a while to figure out one of the scenes when he actually runs
over somebody else.  Sounds like a bunch of characters you would want to
have around to keep a pwa event a bit less uptight.

Best,

Rich

 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by Vaughan James Sander » Sat, 19 Dec 1998 04:00:00



Quote:
>Jamie:

>So what does the board want to do when it is tail walking?  I understand
>how it happens (sheeting out at speed, loss of mfp), but do not know
>what happens to the board before you go down.

Rich this usually happens when you are over powered and get hit by a
gust.
The nose will want to lift and you have to sheet in to keep the nose
down. For a few seconds you will be riding on the fin until you regain
control. If you sheet out the board will stand on it's tail. If you can
stay on long enough the board will slow and come back down again. Not
much use if your racing though, you usually get catapulted anyway.

Quote:

>Dave White and Peter Hart seem to have a great time together in the
>Fuerte video.  I guess he has a bit more "insulation" when compared to
>many of the rest of us to let him sail at high speeds and do some of
>that funny stuff.  Peter Hart seemed to like including the helmet shots
>of White wiping out during his jibes at the end of the speed course.  It
>took me a while to figure out one of the scenes when he actually runs
>over somebody else.  Sounds like a bunch of characters you would want to
>have around to keep a pwa event a bit less uptight.

>Best,

>Rich

The only pwa event I've seen, is the WC at Brighton here in the UK.
Ive managed to get down for a couple of days every year it has been on.
Unfortunately it did not take place this year. It would have been on
when the Transatlantic race was taking place. It would be good if they
staged the TAWR to finish on Brighton beach and go straight in to a WC
event. Apart from not seeing the latest equipment that the WC stars are
using. I've also missed seeing all the latest production stuff under
one roof. They erect a big show hall on the beach and have all the new
equipment from the ISPO German trade fair on display.
Brighton is famous for it's *** shore break and is the place to be
if you want to see uptight pissed off WC stars, when their rigs are
getting mangled to shreds in the surf. The waves rear up very close to
the beach and smash down with tremendous force. The local sailors like
Nik Baker and Jamie Hawkins sail straight at the beach, land and are
running up the beach hardly coming off the plane. Most who are there for
the first time tend to hang back and try to land on the back of a wave.
As the under toe is so strong, and much to the amu***t of the crowd on
the beach, they are usually dragged back and hammered by the next wave.
They have volunteers in wet suits on the beach to run in and drag them
out, but by this time it is usually to late for their rigs.
One year at high tide the break was so big and as too much equipment was
getting trashed, they had to hold the racing for awhile. The pwa film
crew wanted a volunteer, to film getting mangled in the shore break.
Dave was up for it, although it meant sacrificing his rig, but wanted it
to be for real and not staged. He made a dozen or so launches and
landings and made it every time.
BTW Peter Hart does the commentary at Brighton.

Jamie

Jamie Sanders
Chalkwell Windsurfing Club
 http://freespace.***.net/ken.rosier/cwc.htm                        

--
Vaughan James Sanders

 
 
 

Tail Walk / Fin Riding Excerpt from article

Post by RJ Associate » Sat, 19 Dec 1998 04:00:00

Jamie:

I saw some of the pictures last year of the Brighton race, and I was
surprised to see how much broken gear there was for what appeared to be
fairly small looking break.  It must have been a lighter day during the
race, but I guess if the toe is so strong you get caught in never never
land.

You may not miss the race again if the TAWR was a one time deal.  I
wonder if they could or would want to pull it off again?  I would bet
that they would have to use a different ship which is more stable in
high seas, improve the launching and loading of boards, and somehow
resolve the problem of racers going so much faster than the ship.
Dropping sailors off and having them wait on their boards for however
long until the race starts has got to be a deal breaker in rough seas.
Having them sail way past the ship wouldn't be good from the standpoint
of viewership.  Sailing in the wake of the ship and then sprinting may
be okay for a while, but that would get old after a while.  It's neat
that they did it, but I just wonder if it'll happen again.  

You may just have the Brighton race back.  Plus, with a beer sponsor
again, you might just get a good party too.  Maybe a one day race across
the channel would be more of a race than across the Atlantic?   A sprint
from England to France, that could generate some publicity and be lots
easier logistically than US to UK.

Rich

Quote:



> >Jamie:

> >So what does the board want to do when it is tail walking?  I understand
> >how it happens (sheeting out at speed, loss of mfp), but do not know
> >what happens to the board before you go down.

> Rich this usually happens when you are over powered and get hit by a
> gust.
> The nose will want to lift and you have to sheet in to keep the nose
> down. For a few seconds you will be riding on the fin until you regain
> control. If you sheet out the board will stand on it's tail. If you can
> stay on long enough the board will slow and come back down again. Not
> much use if your racing though, you usually get catapulted anyway.

> >Dave White and Peter Hart seem to have a great time together in the
> >Fuerte video.  I guess he has a bit more "insulation" when compared to
> >many of the rest of us to let him sail at high speeds and do some of
> >that funny stuff.  Peter Hart seemed to like including the helmet shots
> >of White wiping out during his jibes at the end of the speed course.  It
> >took me a while to figure out one of the scenes when he actually runs
> >over somebody else.  Sounds like a bunch of characters you would want to
> >have around to keep a pwa event a bit less uptight.

> >Best,

> >Rich

> The only pwa event I've seen, is the WC at Brighton here in the UK.
> Ive managed to get down for a couple of days every year it has been on.
> Unfortunately it did not take place this year. It would have been on
> when the Transatlantic race was taking place. It would be good if they
> staged the TAWR to finish on Brighton beach and go straight in to a WC
> event. Apart from not seeing the latest equipment that the WC stars are
> using. I've also missed seeing all the latest production stuff under
> one roof. They erect a big show hall on the beach and have all the new
> equipment from the ISPO German trade fair on display.
> Brighton is famous for it's *** shore break and is the place to be
> if you want to see uptight pissed off WC stars, when their rigs are
> getting mangled to shreds in the surf. The waves rear up very close to
> the beach and smash down with tremendous force. The local sailors like
> Nik Baker and Jamie Hawkins sail straight at the beach, land and are
> running up the beach hardly coming off the plane. Most who are there for
> the first time tend to hang back and try to land on the back of a wave.
> As the under toe is so strong, and much to the amu***t of the crowd on
> the beach, they are usually dragged back and hammered by the next wave.
> They have volunteers in wet suits on the beach to run in and drag them
> out, but by this time it is usually to late for their rigs.
> One year at high tide the break was so big and as too much equipment was
> getting trashed, they had to hold the racing for awhile. The pwa film
> crew wanted a volunteer, to film getting mangled in the shore break.
> Dave was up for it, although it meant sacrificing his rig, but wanted it
> to be for real and not staged. He made a dozen or so launches and
> landings and made it every time.
> BTW Peter Hart does the commentary at Brighton.

> Jamie

> Jamie Sanders
> Chalkwell Windsurfing Club
>  http://freespace.***.net/ken.rosier/cwc.htm

> --
> Vaughan James Sanders