Question for Carl - steering a pair

[KC]

Anyone can respond (obviously) but I'd like to hear Carl's take on this:

Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.

I often find myself disputing the claim that a pair is faster with a
rudder than without. Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.

My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit. But I've not done any actual analysis of the problem. With older
less efficient rudders, it was obvious. But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.

So I'm curious what you would say.

All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.

IME, I've always removed rudders from all pairs I've used or coached. I
think rowers learn to row better that way.

Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.

Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course. This also just
seems less efficient to me. So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best. But I'm surprised how many people disagree.

So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?

-KC

[p***@hotmail.com]

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without.  Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit.  But I've not done any actual analysis of the problem.  With older
less efficient rudders, it was obvious.  But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached.  I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course.  This also just
seems less efficient to me.  So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best.  But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

Realizing, of course, that "perfectly matched to go straight in a
pair", is not "perfectly matched" as might be done with matching force
profiles as closely as possible (which is beneficial in 2x's and 4x's,
and perhaps 4's and 8's).

The 2- is unique in that you actually want the bow to be a bit less
efficient in profile, i.e. have a less front loaded force profile.

I can't be totally sure on the rudder issue, and tend to agree that
simple straight tracking would be the most efficient use of power.
That said, and as has been said previously, "The fastest speed is
rarely accomplished in the most efficient manner."
Also, it seemed that the C1 Flat water paddlers might employ a
constant offset rudder to aid in their straight tracking, but I've
never examined one of those boats close enough to know.

Anecdotal, but topical bit:
I stroked a M4+ back in our College Regional Regatta where the cox
asked port side to "ease up a bit" since he was having to stay on the
rudder, we did what he asked, went straight, but started to lose
ground; I decided to power back up and let him stay on the rudder
(very large and clumsy thing hanging off the very stern of Old Pocock
boats), to the end that we regained a bit of ground that was lost, and
though we didn't win, we did at least place. Not a real shining
moment for efficiency, but there are some cases where brute force can
work out, at least better than not, when you can't ask the starboards
to "man up" NOW. [;o)

- Paul Smith

[KC]

Post by p***@hotmail.com

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without. Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit. But I've not done any actual analysis of the problem. With older
less efficient rudders, it was obvious. But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached. I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course. This also just
seems less efficient to me. So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best. But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

Realizing, of course, that "perfectly matched to go straight in a
pair", is not "perfectly matched" as might be done with matching force
profiles as closely as possible (which is beneficial in 2x's and 4x's,
and perhaps 4's and 8's).

Yes, well aware of that. For those that aren't there's a good plot of
the different force curve shapes in a pair, in the book, _Rowing Faster_
by Nolte. I think Valery Kleshnev might have some on his site too.

Post by p***@hotmail.com
The 2- is unique in that you actually want the bow to be a bit less
efficient in profile, i.e. have a less front loaded force profile.

Yep.

Post by p***@hotmail.com
I can't be totally sure on the rudder issue, and tend to agree that
simple straight tracking would be the most efficient use of power.
That said, and as has been said previously, "The fastest speed is
rarely accomplished in the most efficient manner."
Also, it seemed that the C1 Flat water paddlers might employ a
constant offset rudder to aid in their straight tracking, but I've
never examined one of those boats close enough to know.

I'm pretty sure they are rudderless. It's called a "J-stroke" with
which you correct your course every stroke.

Post by p***@hotmail.com
I stroked a M4+ back in our College Regional Regatta where the cox
asked port side to "ease up a bit" since he was having to stay on the
rudder, we did what he asked, went straight, but started to lose
ground; I decided to power back up and let him stay on the rudder
(very large and clumsy thing hanging off the very stern of Old Pocock
boats), to the end that we regained a bit of ground that was lost, and
though we didn't win, we did at least place. Not a real shining
moment for efficiency, but there are some cases where brute force can
work out, at least better than not, when you can't ask the starboards
to "man up" NOW. [;o)

I still row with the same M4+ we had in college. We only row a couple
times a year now, though. We still joke about stbd or port being the
weaker side, but truth is, our coxswain claims she doesn't have to use
the rudder at all on straight stretches, and never did. We've always
done quite well as a 4+, but unfortunately rarely had a well matched
other 4 to fill out our Univeristy 8+.

As for pairs, I've rowed with both ports in that 4+ and we've never used
a rudder, and always did quite well. Steering problems usually came
down to a matter of who was in better shape at the time.

-KC

-KC

[Matt Kaminski]

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without. Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a little
rudder than to row sans rudder and force said rower to back off a bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit. But I've not done any actual analysis of the problem. With older
less efficient rudders, it was obvious. But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached. I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget it)
with one rower over powering the other, you'd have to constantly have the
rudder on then off, then on, then off, etc., so as not to turn during the
recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course. This also just
seems less efficient to me. So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best. But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing the
stronger rower to row all out, and using a highly efficient rudder to
compensate?
-KC

Interesting and I would like to add my thoughts as a rower/coach.

Yes I would agree and also would be the first to remove a rudder. Maybe more
psychological than scientific - I hope Carl will add his knowledge on this.

Having said that, I have spent equal time with and without a rudder in a
pair. I was also the one that did the steering in either the bow or stroke
seats. Someone told me it was faster without a rudder but I can't confirm
it. It sounded good and I have been rowing on a really boring straight
stretch so no need anyway. Having a good partner helps - the stern will tell
that person a lot if they know what they are doing.

I do like the rudder and it does make adjustments much easier. You can keep
your rowing more consistent and not have to adjust timing/pressure when
adjusting your course. Yes I know there will be people who say if you can't
go straight you aren't rowing correctly but there is always something that
happens you have to adjust for.

On twisty rivers/courses a rudder is nice and I would prefer one. Even a
coxed pair is fun on a meandering stretch (those youngsters on here just
don't know what you are missing). Does anyone still race coxed pairs in head
races anymore?? When did Walton Small Boats stop - sorry, been out of the
country for 20 years.

Then again a pair with no rudder isn't much different than a single sculler.
No rudder so blade pressure turns the boat. If it was faster someone would
have put a rudder in by now.

On that note some people swear by a mirror when sculling. They say they can
keep the hull speed higher without all that turning around. Confirmed by
them by the speed coach. Maybe it's not the rudder but all that rubber
necking.

Personally I say do whatever works for you. If it makes you happy go for it.

Matt

[Carl Douglas]

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without. Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit. But I've not done any actual analysis of the problem. With older
less efficient rudders, it was obvious. But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached. I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course. This also just
seems less efficient to me. So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best. But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

That's a damned good question, KC.

ISTR a Yugoslav 2- coming sideways up the course in the final in Seoul,
into 3rd place??

Even so, I'm right with you on this one.

Whenever you have to apply rudder, you put the stern sideways & align
the boat (temporarily, at least) just a bit across the course it is
taking. Boats make their least drag when moving perfectly along their
major axis, & drag starts to build significantly for even quite small
off-axis angles. And any wandering in the course taken imposes just
such a drag penalty each time the boat deflects from the straight line
or the optimum bend path on a non-straight course, & each time that
deflection is corrected.

One great advantage of a properly designed steering foil (AeRowFin) is
that it really does respond effectively & immediately to control course
deflections or implement steering inputs. Being very positive, it curbs
the wandering tendency which is the consequence of the plain
inefficiency & unresponsiveness of tin-plate rudder-&-skeg systems.
being precisely progressive in its action, you don't get lags in
response to steering inputs followed by delayed over-reaction.

You posit the case of rowers of unmatched performance. And I would note
that, of all rowing shells, a pair has the most imbalanced of
side-forces through the rowing stroke. So rower performance is always
going to be that bit hard to adjust to prevent any wiggles in their
course. The fact of this imbalance may explain why quite a few top
pairs have gone really well with a lighter, maybe leaner, bowman who can
adjust his stroke force profile & length to keep the boat straight with
the least possible use of rudder.

So I would like any pair learn to balance strokes in such a way as to
optimise their unsteered course. To that end, I really do favour pairs
training rudderless (but not without a fin/skeg, since the lack of that
would allow the boat to yaw uncontrollably). To those who worry about
the consequences of the pair veering off course one need only ask why
this is never their concern for doubles, which go both rudderless & a
bit faster than pairs. We don't put rudders on singles, even though
many scullers start to lose control with 1 arm before the other weakens.
A would-be fast pair should always benefit from treating their boat as
a 2-man 1x, becoming so sensitive to each other's actions that the boat
does run true to the intended course. Only in races should they be
given a rudder (if they want it), & that's because if, in extremis at
the end of a race, one or other does start to blow then it should still
be possible to keep the boat in its lane. If they are far enough ahead
& close enough to the finish, they may then still win.

Does that answer your question?

Cheers -
Carl

[KC]

Post by Carl Douglas

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without. Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off
a bit.
My analytical intuition says that it would always be faster to row
such that you don't need a rudder, even if that means one person backs
off a bit. But I've not done any actual analysis of the problem.
With older less efficient rudders, it was obvious. But with a highly
efficient hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached.
I think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to
turn during the recovery.
Or, you find a setting that allows you to keep it on, and you just
live with a little fish-tailing, but a net straight course. This also
just seems less efficient to me. So long as the stronger rower is
mentally able to do it, I would think having him back off to match his
partner would be best. But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

That's a damned good question, KC.
ISTR a Yugoslav 2- coming sideways up the course in the final in Seoul,
into 3rd place??
Even so, I'm right with you on this one.
Whenever you have to apply rudder, you put the stern sideways & align
the boat (temporarily, at least) just a bit across the course it is
taking. Boats make their least drag when moving perfectly along their
major axis, & drag starts to build significantly for even quite small
off-axis angles. And any wandering in the course taken imposes just
such a drag penalty each time the boat deflects from the straight line
or the optimum bend path on a non-straight course, & each time that
deflection is corrected.
One great advantage of a properly designed steering foil (AeRowFin) is
that it really does respond effectively & immediately to control course
deflections or implement steering inputs. Being very positive, it curbs
the wandering tendency which is the consequence of the plain
inefficiency & unresponsiveness of tin-plate rudder-&-skeg systems.
being precisely progressive in its action, you don't get lags in
response to steering inputs followed by delayed over-reaction.
You posit the case of rowers of unmatched performance. And I would note
that, of all rowing shells, a pair has the most imbalanced of
side-forces through the rowing stroke. So rower performance is always

Paul kind of pointed out the same thing. I had this in mind when I
referred to a matched (or unmatched) pair. So to clarify (& sorry for
not doing so earlier) define a "well matched pair" for rowing a 2- as a
pair of rowers who's force profiles compliment each other to the extent
that they row straight when going all out in a 2- w/o rudder (a 2-- if
you will). :^)

Post by Carl Douglas
going to be that bit hard to adjust to prevent any wiggles in their
course. The fact of this imbalance may explain why quite a few top
pairs have gone really well with a lighter, maybe leaner, bowman who can
adjust his stroke force profile & length to keep the boat straight with
the least possible use of rudder.

Now then, who's the lean & lighter one: Redgrave or Pinsent? ;^) I
agree though, if you have two guys who want to learn to row the pair,
generally put the weaker or smaller one in bow... or the more
technically skilled one if they are equal in size & strength.

Post by Carl Douglas
So I would like any pair learn to balance strokes in such a way as to
optimise their unsteered course. To that end, I really do favour pairs
training rudderless (but not without a fin/skeg, since the lack of that
would allow the boat to yaw uncontrollably). To those who worry about
the consequences of the pair veering off course one need only ask why
this is never their concern for doubles, which go both rudderless & a
bit faster than pairs. We don't put rudders on singles, even though
many scullers start to lose control with 1 arm before the other weakens.

Yes, I've seen that a lot. I've not coached scullers much, but I see
it, and have struggled with it when I (rarely) take out a 1x myself.

Post by Carl Douglas
A would-be fast pair should always benefit from treating their boat as
a 2-man 1x, becoming so sensitive to each other's actions that the boat

Those words, almost verbatim, have come before from my own mouth
directed at my 2- rowers.

Post by Carl Douglas
does run true to the intended course. Only in races should they be
given a rudder (if they want it), & that's because if, in extremis at
the end of a race, one or other does start to blow then it should still
be possible to keep the boat in its lane. If they are far enough ahead
& close enough to the finish, they may then still win.
Does that answer your question?

Partly, although not much more than how I have tried to answer it
myself. :^) Although I had not thought of the additional drag from the
hull when it's in a state of yaw wrt it's course...

Thanks,
KC

[Pete]

Post by Carl Douglas
One great advantage of a properly designed steering foil (AeRowFin) is
that it really does respond effectively & immediately to control course
deflections or implement steering inputs. Being very positive, it curbs
the wandering tendency which is the consequence of the plain
inefficiency & unresponsiveness of tin-plate rudder-&-skeg systems.
being precisely progressive in its action, you don't get lags in
response to steering inputs followed by delayed over-reaction.

It's clear that the 'modern' rudder system, with a tin-plate rudder
immediately behind the skeg, is inefficient. The rudder and skeg work
against each other whenever there's any steering, and the rudder's
effect is almost entirely a reaction-friction force, wasting a lot of
power.

Unless I'm missing something, it would actually be more efficient
(though still maybe not perfect) to simply remove the skeg: the rudder
can do that job itself. Of course, then you need to be very careful
with steering (very small angles, really getting 'straight' right) or
you'll throw the boat about and lose distance fast. The hull will
still have some 'skeg' action and steering will still be inefficient -
but I guess there's some unavoidable inefficiency.

When there is a boat with a significant tendency to pull round (i.e. a
pair...), I'd guess that a widely separated rudder and skeg (classic
system, with the skeg a few feet down the stern and the rudder on the
stern) is actually not so bad: simply because the rudder will usually
be held straight, so it acts as an extra skeg - and that means you
have a fairly decent, and efficient, resistance to the boat turning.

Post by Carl Douglas
You posit the case of rowers of unmatched performance. And I would note
that, of all rowing shells, a pair has the most imbalanced of
side-forces through the rowing stroke. So rower performance is always
going to be that bit hard to adjust to prevent any wiggles in their
course. The fact of this imbalance may explain why quite a few top
pairs have gone really well with a lighter, maybe leaner, bowman who can
adjust his stroke force profile & length to keep the boat straight with
the least possible use of rudder.

Anyone can adjust their stroke profile, whether they weigh 80kg or
120kg. The difference is simply that in the second case there's 40kg
more to haul down the course. The main reason for a rudder is that if
the bowman manages to blow himself up, the last thing he wants to be
doing is telling stroke to ease off. It may be the right thing to keep
the boat straight, but the athletes are people with psychologies, you
can't simply ignore that. A boat with one guy feeling like a loser
who's had to admit he's blown and one guy furious with his partner for
blowing in the final will definitely go slowly (or in circles), even
compared to a boat with the stroke-man mainly working against the
inefficient rudder.

Incidentally, I'd point out that a lot of boats really don't react
that badly when there is no skeg. This comes from personal experience
of losing rather too many: in eights or quads you really don't have to
change anything (if you were going OK before), in fours you only need
to be a little careful (you should not be monkeying it along
anyway..). No experience with smaller boats minus skeg.

Pete

[KC]

Post by Pete

Post by Carl Douglas
One great advantage of a properly designed steering foil (AeRowFin) is
that it really does respond effectively & immediately to control course
deflections or implement steering inputs. Being very positive, it curbs
the wandering tendency which is the consequence of the plain
inefficiency & unresponsiveness of tin-plate rudder-&-skeg systems.
being precisely progressive in its action, you don't get lags in
response to steering inputs followed by delayed over-reaction.

It's clear that the 'modern' rudder system, with a tin-plate rudder
immediately behind the skeg, is inefficient. The rudder and skeg work
against each other whenever there's any steering, and the rudder's
effect is almost entirely a reaction-friction force, wasting a lot of
power.

While the tin-plate system of skeg + rudder is clearly less efficient
than an optimized combo like that of the aerowfin, the tin rudder and
tin skeg do NOT work against each other. They work together, just like
a wing on an airplane which has a rudder of sorts attached to it's
trailing edge (called an aileron in that case) or the actual tale of
most aircraft which is a rudder + vertical "fin". Just because they are
flat tin plates, does not mean they don't work together.

Post by Pete
Unless I'm missing something, it would actually be more efficient
(though still maybe not perfect) to simply remove the skeg: the rudder
can do that job itself. Of course, then you need to be very careful

The rudder would have to be a lot bigger to achieve the same amount of
lift by itself without the fin/skeg attached to it. In so doing the
larger fin-less rudder would also produce much more drag than it would
as a smaller sized trailing edge rudder to a fin.

You see, lift is proportional to the area of a foil. The skeg/fin
increases the area of the lifting surface, such that a smaller
deflection angle of the rudder is needed to achieve the same amount of
lifting force, & therefore there's less drag.

-KC

[KC]

Post by KC

Post by Pete

Post by Carl Douglas
One great advantage of a properly designed steering foil (AeRowFin) is
that it really does respond effectively & immediately to control course
deflections or implement steering inputs. Being very positive, it curbs
the wandering tendency which is the consequence of the plain
inefficiency & unresponsiveness of tin-plate rudder-&-skeg systems.
being precisely progressive in its action, you don't get lags in
response to steering inputs followed by delayed over-reaction.

It's clear that the 'modern' rudder system, with a tin-plate rudder
immediately behind the skeg, is inefficient. The rudder and skeg work
against each other whenever there's any steering, and the rudder's
effect is almost entirely a reaction-friction force, wasting a lot of
power.

While the tin-plate system of skeg + rudder is clearly less efficient
than an optimized combo like that of the aerowfin, the tin rudder and
tin skeg do NOT work against each other. They work together, just like
a wing on an airplane which has a rudder of sorts attached to it's
trailing edge (called an aileron in that case) or the actual tale of
most aircraft which is a rudder + vertical "fin". Just because they are
flat tin plates, does not mean they don't work together.

Nice speelink there, KC. "its" not "it's" and "tail" not "tale". :^P

Post by KC

Post by Pete
Unless I'm missing something, it would actually be more efficient
(though still maybe not perfect) to simply remove the skeg: the rudder
can do that job itself. Of course, then you need to be very careful

The rudder would have to be a lot bigger to achieve the same amount of
lift by itself without the fin/skeg attached to it. In so doing the
larger fin-less rudder would also produce much more drag than it would
as a smaller sized trailing edge rudder to a fin.
You see, lift is proportional to the area of a foil. The skeg/fin
increases the area of the lifting surface, such that a smaller
deflection angle of the rudder is needed to achieve the same amount of
lifting force, & therefore there's less drag.
-KC

[Peter Ford]

Post by Carl Douglas

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without.  Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit.  But I've not done any actual analysis of the problem.  With older
less efficient rudders, it was obvious.  But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached.  I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course.  This also just
seems less efficient to me.  So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best.  But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

That's a damned good question, KC.
ISTR a Yugoslav 2- coming sideways up the course in the final in Seoul,
into 3rd place??
Even so, I'm right with you on this one.
Whenever you have to apply rudder, you put the stern sideways & align
the boat (temporarily, at least) just a bit across the course it is
taking.  Boats make their least drag when moving perfectly along their
major axis, & drag starts to build significantly for even quite small
off-axis angles.  And any wandering in the course taken imposes just
such a drag penalty each time the boat deflects from the straight line
or the optimum bend path on a non-straight course, & each time that
deflection is corrected.
One great advantage of a properly designed steering foil (AeRowFin) is
that it really does respond effectively & immediately to control course
deflections or implement steering inputs.  Being very positive, it curbs
the wandering tendency which is the consequence of the plain
inefficiency & unresponsiveness of tin-plate rudder-&-skeg systems.
being precisely progressive in its action, you don't get lags in
response to steering inputs followed by delayed over-reaction.
You posit the case of rowers of unmatched performance.  And I would note
that, of all rowing shells, a pair has the most imbalanced of
side-forces through the rowing stroke.  So rower performance is always
going to be that bit hard to adjust to prevent any wiggles in their
course.  The fact of this imbalance may explain why quite a few top
pairs have gone really well with a lighter, maybe leaner, bowman who can
adjust his stroke force profile & length to keep the boat straight with
the least possible use of rudder.
So I would like any pair learn to balance strokes in such a way as to
optimise their unsteered course.  To that end, I really do favour pairs
training rudderless (but not without a fin/skeg, since the lack of that
would allow the boat to yaw uncontrollably).  To those who worry about
the consequences of the pair veering off course one need only ask why
this is never their concern for doubles, which go both rudderless & a
bit faster than pairs.  We don't put rudders on singles, even though
many scullers start to lose control with 1 arm before the other weakens.
  A would-be fast pair should always benefit from treating their boat as
a 2-man 1x, becoming so sensitive to each other's actions that the boat
does run true to the intended course.  Only in races should they be
given a rudder (if they want it), & that's because if, in extremis at
the end of a race, one or other does start to blow then it should still
be possible to keep the boat in its lane.  If they are far enough ahead
& close enough to the finish, they may then still win.
Does that answer your question?
Cheers -
Carl
--
Carl Douglas Racing Shells        -
     Fine Small-Boats/AeRoWing Low-drag Riggers/Advanced Accessories
Write:   Harris Boatyard, Laleham Reach, Chertsey KT16 8RP, UK
Find:    http://tinyurl.com/2tqujf
URLs:  www.carldouglas.co.uk(boats) &www.aerowing.co.uk(riggers)

I'm not sure you or others are answering quite the question KC asked,
at least as I understand it; obviously its a good idea if a pair can
row in a straight line rudderless, but if the imbalance in power and
effectiveness is such that the stronger rower's only two options are
to either keep the rudder on or to row at a pace sustainable by them
for many times the race distance, the question is which is more
effective (or rather where on the continuum between the two).

As a separate issue, I have done some training in a rudderless pair,
both in Worcester and on the Cam. With the former, I had little
problem, but on the Cam, the corners are just too annoying; even with
a (standard rubbish) rudder you have to go to about ghost pressure on
one side to get round some of them. On a similar vein, I strongly
suspect that a single with a rudder would be quicker for racing the
bends on the Cam, or maybe the retractable rudders I seem to remember
discussion of from some eights of the past?

As for the idea of racing without rudders, I'd be less concerned about
the finish but rather about the start, where you have both the
possibility of spinning round due to launch wash/other waves
temporarily displacing one blade from the water at the first drive, or
differing reaction times.

Peter

[Christopher Kerr]

Post by Peter Ford
As a separate issue, I have done some training in a rudderless pair,
both in Worcester and on the Cam. With the former, I had little
problem, but on the Cam, the corners are just too annoying; even with
a (standard rubbish) rudder you have to go to about ghost pressure on
one side to get round some of them. On a similar vein, I strongly
suspect that a single with a rudder would be quicker for racing the
bends on the Cam, or maybe the retractable rudders I seem to remember
discussion of from some eights of the past?
Peter

In a sculling boat, easing off on one side (to the extent that you need to
do to go round the corners on the Cam) allows you to increase the pressure
on the other side (although admittedly not to twice as much as when rowing
with both oars) so there is less of a speed disadvantage than with a pair.

A rudder would, however, give the advantage of not having to start steering
for Grassy 5 metres too early or too late if you don't time your strokes
properly up the Gut. (Anyone who can remember to do that in a race gets big
respect from me)

[Peter Ford]

Post by Christopher Kerr

Post by Peter Ford
As a separate issue, I have done some training in a rudderless pair,
both in Worcester and on the Cam. With the former, I had little
problem, but on the Cam, the corners are just too annoying; even with
a (standard rubbish) rudder you have to go to about ghost pressure on
one side to get round some of them. On a similar vein, I strongly
suspect that a single with a rudder would be quicker for racing the
bends on the Cam, or maybe the retractable rudders I seem to remember
discussion of from some eights of the past?
Peter

In a sculling boat, easing off on one side (to the extent that you need to
do to go round the corners on the Cam) allows you to increase the pressure
on the other side (although admittedly not to twice as much as when rowing
with both oars) so there is less of a speed disadvantage than with a pair.

True.

Post by Christopher Kerr
A rudder would, however, give the advantage of not having to start steering
for Grassy 5 metres too early or too late if you don't time your strokes
properly up the Gut. (Anyone who can remember to do that in a race gets big
respect from me)

Starting steering for grassy I don't find as much of a problem,
various start points can be right in a single because it's so
(relatively) easy to make a big course correction on one stroke. What
I still haven't got the hang of is stopping steering for grassy, I
think it's the fact you always come round on a slightly different line
that makes it hard to pick up the straight. Hence ending up wide,
overcorrecting, and heading for the grey barge... The corner that I
wanted a rudder for was Ditton, its length being the annoying feature.

In reply to the question about mirrors, I tried a mirror that clipped
to sunglasses for sculling in Worcester; I think it had potential, but
I found it very difficult to get used to pointing my head the right
way to see something; it would certainly be difficult to gain enough
awareness of which way the boat was going to steer by it on the Cam,
but for collision avoidance could well be useful. No substitute for
making sure you're always in the right place on the river, but it
might give you a clue as to when it matters to get back to the right
line.

Peter

[MagnusBurbanks]

Post by Peter Ford

Post by Christopher Kerr

Post by Peter Ford
As a separate issue, I have done some training in a rudderless pair,
both in Worcester and on the Cam. With the former, I had little
problem, but on the Cam, the corners are just too annoying; even with
a (standard rubbish) rudder you have to go to about ghost pressure on
one side to get round some of them. On a similar vein, I strongly
suspect that a single with a rudder would be quicker for racing the
bends on the Cam, or maybe the retractable rudders I seem to remember
discussion of from some eights of the past?
Peter

In a sculling boat, easing off on one side (to the extent that you need to
do to go round the corners on the Cam) allows you to increase the pressure
on the other side (although admittedly not to twice as much as when rowing
with both oars) so there is less of a speed disadvantage than with a pair.

True.

Post by Christopher Kerr
A rudder would, however, give the advantage of not having to start steering
for Grassy 5 metres too early or too late if you don't time your strokes
properly up the Gut. (Anyone who can remember to do that in a race gets big
respect from me)

Starting steering for grassy I don't find as much of a problem,
various start points can be right in a single because it's so
(relatively) easy to make a big course correction on one stroke. What
I still haven't got the hang of is stopping steering for grassy, I
think it's the fact you always come round on a slightly different line
that makes it hard to pick up the straight. Hence ending up wide,
overcorrecting, and heading for the grey barge... The corner that I
wanted a rudder for was Ditton, its length being the annoying feature.
In reply to the question about mirrors, I tried a mirror that clipped
to sunglasses for sculling in Worcester; I think it had potential, but
I found it very difficult to get used to pointing my head the right
way to see something; it would certainly be difficult to gain enough
awareness of which way the boat was going to steer by it on the Cam,
but for collision avoidance could well be useful. No substitute for
making sure you're always in the right place on the river, but it
might give you a clue as to when it matters to get back to the right
line.
Peter- Hide quoted text -
- Show quoted text -

I use a rear-view mirror for my twice-daily 10 mile cycle in London
traffic to and from work. It's a mirror built in to the helmet,
formerly made by a manufacturer called Reevu, but discontinued I
assume due to poor sales. Like a glasses-attached mirror, to look
behind-left you need to point your face right, which feels odd to
begin with. However you soon get used to it and now I could not
imagine cycling without it. The difference it makes to my traffic-
awareness without having to look behind is quite incredible. Also,
being a sculler and thus more than a little competitive, every journey
is a RACE, and the mirror gives a huge tactical advantage.

Anyway, to my real point. On the basis that the head-pivoting-mirror
is so useful on two wheels, I decided to adopt a spectacles-attached
mirror system while sculling. Once again to begin with it was a little
odd but I persevered.

I never really got comfortable, even after a couple of weeks. The
deciding near-incident occurred when one day I looked around (in the
normal way) to check that the river was indeed clear as the mirror was
indicating, to find about 20 metres ahead an eight turning directly in
front of me mid river. I hadn't been able to see a whole eight
lengthways. I immediately stopped using it for scuilling and rely on
looking round instead.

[m***@googlemail.com]

Post by MagnusBurbanks

Post by Peter Ford

Post by Christopher Kerr

Post by Peter Ford
As a separate issue, I have done some training in a rudderless pair,
both in Worcester and on the Cam. With the former, I had little
problem, but on the Cam, the corners are just too annoying; even with
a (standard rubbish) rudder you have to go to about ghost pressure on
one side to get round some of them. On a similar vein, I strongly
suspect that a single with a rudder would be quicker for racing the
bends on the Cam, or maybe the retractable rudders I seem to remember
discussion of from some eights of the past?
Peter

In a sculling boat, easing off on one side (to the extent that you need to
do to go round the corners on the Cam) allows you to increase the pressure
on the other side (although admittedly not to twice as much as when rowing
with both oars) so there is less of a speed disadvantage than with a pair.

True.

Post by Christopher Kerr
A rudder would, however, give the advantage of not having to start steering
for Grassy 5 metres too early or too late if you don't time your strokes
properly up the Gut. (Anyone who can remember to do that in a race gets big
respect from me)

Starting steering for grassy I don't find as much of a problem,
various start points can be right in a single because it's so
(relatively) easy to make a big course correction on one stroke. What
I still haven't got the hang of is stopping steering for grassy, I
think it's the fact you always come round on a slightly different line
that makes it hard to pick up the straight. Hence ending up wide,
overcorrecting, and heading for the grey barge... The corner that I
wanted a rudder for was Ditton, its length being the annoying feature.
In reply to the question about mirrors, I tried a mirror that clipped
to sunglasses for sculling in Worcester; I think it had potential, but
I found it very difficult to get used to pointing my head the right
way to see something; it would certainly be difficult to gain enough
awareness of which way the boat was going to steer by it on the Cam,
but for collision avoidance could well be useful. No substitute for
making sure you're always in the right place on the river, but it
might give you a clue as to when it matters to get back to the right
line.
Peter- Hide quoted text -
- Show quoted text -

I use a rear-view mirror for my twice-daily 10 mile cycle in London
traffic to and from work. It's a mirror built in to the helmet,
formerly made by a manufacturer called Reevu, but discontinued I
assume due to poor sales. Like a glasses-attached mirror, to look
behind-left you need to point your face right, which feels odd to
begin with. However you soon get used to it and now I could not
imagine cycling without it. The difference it makes to my traffic-
awareness without having to look behind is quite incredible. Also,
being a sculler and thus more than a little competitive, every journey
is a RACE, and the mirror gives a huge tactical advantage.
Anyway, to my real point. On the basis that the head-pivoting-mirror
is so useful on two wheels, I decided to adopt a spectacles-attached
mirror system while sculling. Once again to begin with it was a little
odd but I persevered.
I never really got comfortable, even after a couple of weeks. The
deciding near-incident occurred when one day I looked around (in the
normal way) to check that the river was indeed clear as the mirror was
indicating, to find about 20 metres ahead an eight turning directly in
front of me mid river. I hadn't been able to see a whole eight
lengthways. I immediately stopped using it for scuilling and rely on
looking round instead.- Hide quoted text -
- Show quoted text -

Strange that it should work so well on land and so very nearly
disastrously on water! I can't think why that should be? However,
what I was wondering was whether there are any mirrors one might fit
to a rigger stay? Assuming you had one each side, they should balance
each other and I can't see why they wouldn't work, as long as you
could keep them reasonably smear-free.

[z***@zekehoskin.com]

Post by m***@googlemail.com

Post by MagnusBurbanks

Post by Peter Ford

Post by Christopher Kerr

Post by Peter Ford
As a separate issue, I have done some training in a rudderless pair,
both in Worcester and on the Cam. With the former, I had little
problem, but on the Cam, the corners are just too annoying; even with
a (standard rubbish) rudder you have to go to about ghost pressure on
one side to get round some of them. On a similar vein, I strongly
suspect that a single with a rudder would be quicker for racing the
bends on the Cam, or maybe the retractable rudders I seem to remember
discussion of from some eights of the past?
Peter

In a sculling boat, easing off on one side (to the extent that you need to
do to go round the corners on the Cam) allows you to increase the pressure
on the other side (although admittedly not to twice as much as when rowing
with both oars) so there is less of a speed disadvantage than with a pair.

True.

Post by Christopher Kerr
A rudder would, however, give the advantage of not having to start steering
for Grassy 5 metres too early or too late if you don't time your strokes
properly up the Gut. (Anyone who can remember to do that in a race gets big
respect from me)

Starting steering for grassy I don't find as much of a problem,
various start points can be right in a single because it's so
(relatively) easy to make a big course correction on one stroke. What
I still haven't got the hang of is stopping steering for grassy, I
think it's the fact you always come round on a slightly different line
that makes it hard to pick up the straight. Hence ending up wide,
overcorrecting, and heading for the grey barge... The corner that I
wanted a rudder for was Ditton, its length being the annoying feature.
In reply to the question about mirrors, I tried a mirror that clipped
to sunglasses for sculling in Worcester; I think it had potential, but
I found it very difficult to get used to pointing my head the right
way to see something; it would certainly be difficult to gain enough
awareness of which way the boat was going to steer by it on the Cam,
but for collision avoidance could well be useful. No substitute for
making sure you're always in the right place on the river, but it
might give you a clue as to when it matters to get back to the right
line.
Peter- Hide quoted text -
- Show quoted text -

I use a rear-view mirror for my twice-daily 10 mile cycle in London
traffic to and from work. It's a mirror built in to the helmet,
formerly made by a manufacturer called Reevu, but discontinued I
assume due to poor sales. Like a glasses-attached mirror, to look
behind-left you need to point your face right, which feels odd to
begin with. However you soon get used to it and now I could not
imagine cycling without it. The difference it makes to my traffic-
awareness without having to look behind is quite incredible. Also,
being a sculler and thus more than a little competitive, every journey
is a RACE, and the mirror gives a huge tactical advantage.
Anyway, to my real point. On the basis that the head-pivoting-mirror
is so useful on two wheels, I decided to adopt a spectacles-attached
mirror system while sculling. Once again to begin with it was a little
odd but I persevered.
I never really got comfortable, even after a couple of weeks. The
deciding near-incident occurred when one day I looked around (in the
normal way) to check that the river was indeed clear as the mirror was
indicating, to find about 20 metres ahead an eight turning directly in
front of me mid river. I hadn't been able to see a whole eight
lengthways. I immediately stopped using it for scuilling and rely on
looking round instead.- Hide quoted text -
- Show quoted text -

Strange that it should work so well on land and so very nearly
disastrously on water!  I can't think why that should be?  However,
what I was wondering was whether there are any mirrors one might fit
to a rigger stay?  Assuming you had one each side, they should balance
each other and I can't see why they wouldn't work, as long as you
could keep them reasonably smear-free.- Hide quoted text -
- Show quoted text -

Tried that. REALLY didn't like it. Remember, you are bobbing back and
forth with respect to the riggers, and the world ahead won't stay put.
Headbound-mounted mirrors worked kind of okay for me, except I broke
them a lot. My operating notion is that no purely optical system will
be good enough, but a pair of little little vidcams
and VR goggles could feel exactly like eyes on the back of your head.
Surely somebody has tried it by now?

[Mike De Petris]

Post by Carl Douglas
To those who worry about
the consequences of the pair veering off course one need only ask why
this is never their concern for doubles, which go both rudderless & a
bit faster than pairs.  We don't put rudders on singles, even though
many scullers start to lose control with 1 arm before the other weakens.

In my personal experience, I've always found the double as the worse
boat to keep straight. This is why I did some races with a rudder, as
we were using that shell as a pair too, and that was really a relief,
as fighting with your double partner about where to go, in a multiple
lanes race without lanes with waves and crosswind is a nightmare. I
can say at a low level of competition, with balance and evironmental
problems to care about, a rudder is beneficial as you can concentrate
on other things, as is is good for training too, when there is boat
traffic, you can simply put your effort on other things in a safe way,
there are still many occasions where I would find it nice having it in
the single, not racing btw, at least because it is much easier to have
all the crew do the same thing to correct the path :-)

It also happened to me to suddenly loose the fin in doubles and
singles, you may not notice that you hit an object that takes it away,
but you will do it at the next stroke, as the effect is devastating,
you can't control the boat and have to come back slow, it's like
putting you wheels on oil in a turn during a car race.

I did a lot of coxing too, when I was joung, so I want to keep out
again the old subject, better to turn the rudder when blades are out
or in? Or better not to vary pressure on rudder during stroke cycle?
Even with strong and big turns?

[w***@gmail.com]

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without.  Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit.  But I've not done any actual analysis of the problem.  With older
less efficient rudders, it was obvious.  But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached.  I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course.  This also just
seems less efficient to me.  So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best.  But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

I'd suggest a lot of training without a rudder, but come race day it
would be stupid to put a rudder back in the boat if they haven't
practiced with one. At least several weeks of training prior to race
day with a rudder, so that they can keep it straight when it's
appropriate, and steer with skill when they need to. If you plunk a
rudder into a boat when people haven't been training with one, it can
lead to rather bendy courses... Steering into a cross wind, steering
on a river course, getting off the buoys, etc., are all skills that
need practice just as much as does balance, entry timing, balanced
releases, etc...

The research I've seen (McBride, then of AIS) (and done with Sask
Rowing and the 1991 world, 1992 Olympic women's 2- champs) on people
who row a lot of pairs suggests that the stroke (whether on the left
or right) has to have a quicker uptake to peak force than bow, to
overcome bow's leverage advantage at the catch - the bow seat (again,
what ever side they're on) benefits by having a slightly later peak
force.

[ben]

Post by w***@gmail.com

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without.  Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit.  But I've not done any actual analysis of the problem.  With older
less efficient rudders, it was obvious.  But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached.  I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course.  This also just
seems less efficient to me.  So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best.  But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

I'd suggest a lot of training without a rudder, but come race day it
would be stupid to put a rudder back in the boat if they haven't
practiced with one.  At least several weeks of training prior to race
day with a rudder, so that they can keep it straight when it's
appropriate, and steer with skill when they need to.  If you plunk a
rudder into a boat when people haven't been training with one, it can
lead to rather bendy courses... Steering into a cross wind, steering
on a river course, getting off the buoys, etc., are all skills that
need practice just as much as does balance, entry timing, balanced
releases, etc...
The research I've seen (McBride, then of AIS) (and done with Sask
Rowing and the 1991 world, 1992 Olympic women's 2- champs) on people
who row a lot of pairs suggests that the stroke (whether on the left
or right) has to have a quicker uptake to peak force than bow, to
overcome bow's leverage advantage at the catch - the bow seat (again,
what ever side they're on) benefits by having a slightly later peak
force.- Hide quoted text -
- Show quoted text -

In that same vein, if you are ever going to race with a rudder --
which you will -- you should probably use it all the time. If you are
just learning to row a pair a rudder would just give you one more
thing to think and is probably unnecessary initially but should be
added later.

The theoretical analyses are interesting, especially coming from the
book Rowing Faster. I was actually coached by Volker Nolte for five
years -- 95% of the time in a pair -- and raced at the World
Championships in the lightweight pair (and even won!). I can't recall
even once ever looking at any force curves or making any effort to
"match" our strokes in the sense that is mentioned in the book. We
always rowed with a rudder (particularly as we were often on lakes
doing head peices around corners) and actually took some pains to make
sure it had the appropriate tension and alignment. So, practically,
I'd take the theory with a grain of salt.

The other thing, from a practical point of view, is that there are two
times when you will unpredictably go off course -- the start and the
finish. Despite rowing with the same partner for hundreds and
hundreds of hours, we would still get slightly off course in the first
20 or the last 20 strokes about 1/3 of the time. This was quite
easily corrected with just a hint of rudder, which we otherwise hardly
used in a race, maybe four or five times down the course. I can't
imagine what it would be like to actually ease off at these times as
it would certainly throw off your balance a bit and particularly the
rythm. Even if you really practiced it, my feeling is that the easing
off or the going in a little early would affect the run of the boat
more than just a tiny bit of rudder. The other thing is that if you
were suddenly in a cross wind and didn't know exactly how to use it it
would be a disaster.

It might be true that the you would be faster rowing without a rudder
if you were "perfectly" matched, but I doubt anyone could actually do
it and there's no way anyone could do it every time. It's obviously
better to use less rudder, but when you're actually racing the pair,
no rudder is just asking for trouble.

[kc]

Post by ben

Post by w***@gmail.com

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without. Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit. But I've not done any actual analysis of the problem. With older
less efficient rudders, it was obvious. But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached. I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course. This also just
seems less efficient to me. So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best. But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

I'd suggest a lot of training without a rudder, but come race day it
would be stupid to put a rudder back in the boat if they haven't
practiced with one. At least several weeks of training prior to race
day with a rudder, so that they can keep it straight when it's
appropriate, and steer with skill when they need to. If you plunk a
rudder into a boat when people haven't been training with one, it can
lead to rather bendy courses... Steering into a cross wind, steering
on a river course, getting off the buoys, etc., are all skills that
need practice just as much as does balance, entry timing, balanced
releases, etc...
The research I've seen (McBride, then of AIS) (and done with Sask
Rowing and the 1991 world, 1992 Olympic women's 2- champs) on people
who row a lot of pairs suggests that the stroke (whether on the left
or right) has to have a quicker uptake to peak force than bow, to
overcome bow's leverage advantage at the catch - the bow seat (again,
what ever side they're on) benefits by having a slightly later peak
force.- Hide quoted text -
- Show quoted text -

In that same vein, if you are ever going to race with a rudder --
which you will -- you should probably use it all the time. If you are
just learning to row a pair a rudder would just give you one more
thing to think and is probably unnecessary initially but should be
added later.

My method for coaching pairs is that they don't get a rudder until they
are rowing & racing at an elite or close to elite level. & even then
they'd need & get lots of practice time w/ the rudder. I've coached
some relatively successful pairs, and they have never raced with a
rudder (nor have I when I rowed & raced a pair) and they had some pretty
intense final 250 meters in several races. But with communication and
maturity, they were all able to handle those situations fine and
remained on course and made some fantastic moves.

Post by ben
The theoretical analyses are interesting, especially coming from the
book Rowing Faster. I was actually coached by Volker Nolte for five
years -- 95% of the time in a pair -- and raced at the World
Championships in the lightweight pair (and even won!). I can't recall
even once ever looking at any force curves or making any effort to

As a coach I never once mentioned the differing force curves to my
rowers. It's not something you coach, or that rowers should strive for.
It's an observation that scientists have made of very good pairs.
Very good pairs who've rowed a lot together, tend to have this sort or
disparity in their force curves. It's just an observation. So I'm not
surprised that you never looked at force curves, or tried to match your
strokes in that way. If you were rowing long enough together, and you
rowed straight at full power with no rudder, then it's very likely that
your force curves DID have that characteristic.

Post by ben
"match" our strokes in the sense that is mentioned in the book. We
always rowed with a rudder (particularly as we were often on lakes
doing head peices around corners) and actually took some pains to make
sure it had the appropriate tension and alignment. So, practically,
I'd take the theory with a grain of salt.

Again, it's not a theory - it's an observation, thus fact: the pairs
observed did indeed exhibit this kind of force curve relationship. This
is not to say that every pair out there does, or should. But some of
the fastest & best pairs at the time showed it, so take that with or
with out salt as you will.

Post by ben
The other thing, from a practical point of view, is that there are two
times when you will unpredictably go off course -- the start and the
finish. Despite rowing with the same partner for hundreds and
hundreds of hours, we would still get slightly off course in the first
20 or the last 20 strokes about 1/3 of the time. This was quite
easily corrected with just a hint of rudder, which we otherwise hardly
used in a race, maybe four or five times down the course. I can't
imagine what it would be like to actually ease off at these times as
it would certainly throw off your balance a bit and particularly the
rythm. Even if you really practiced it, my feeling is that the easing
off or the going in a little early would affect the run of the boat

That's your feeling - but you are biased, for you did your pair rowing
with a rudder. I've never used one, and my crews never have, and thus
my "feeling" is the opposite. I've never had, nor have my crews, this
terrible problem you predict at the start or the finish. It's all about
maturity, knowing your partner, and communication.

This sounds like marriage counseling. ;^) But it's the truth, if you
know and trust your partner, and you know your and his limitations, then
you can predict what's going to happen & deal with it. If you have
enough race experience, then you are even that much more prepared. Each
rower has to have the maturity to either (a) back off when needed, or
(b) ask the other to back off if needed, and not get all mental about it.

Post by ben
more than just a tiny bit of rudder. The other thing is that if you
were suddenly in a cross wind and didn't know exactly how to use it it
would be a disaster.

The cross wind is the only time I think it's worth while to have & know
how to use a rudder. But even then it'd have to be a pretty stiff cross
wind.

If I have a novice, or intermediate, or even some senior (aka pre-elite)
pair, they usually have other/better things to worry about while
training and racing than what the rudder is doing & what they should be
doing with the rudder.

Post by ben
It might be true that the you would be faster rowing without a rudder
if you were "perfectly" matched, but I doubt anyone could actually do
it and there's no way anyone could do it every time. It's obviously
better to use less rudder, but when you're actually racing the pair,
no rudder is just asking for trouble.

To the best of my knowledge, every USA Oly M2- before 1972 rowed a
Pocock without a rudder, and many of them won.

-KC

[Mike Sullivan]

Post by kc

Post by ben

Post by w***@gmail.com

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without. Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit. But I've not done any actual analysis of the problem. With older
less efficient rudders, it was obvious. But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached.
I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course. This also just
seems less efficient to me. So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best. But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

I'd suggest a lot of training without a rudder, but come race day it
would be stupid to put a rudder back in the boat if they haven't
practiced with one. At least several weeks of training prior to race
day with a rudder, so that they can keep it straight when it's
appropriate, and steer with skill when they need to. If you plunk a
rudder into a boat when people haven't been training with one, it can
lead to rather bendy courses... Steering into a cross wind, steering
on a river course, getting off the buoys, etc., are all skills that
need practice just as much as does balance, entry timing, balanced
releases, etc...
The research I've seen (McBride, then of AIS) (and done with Sask
Rowing and the 1991 world, 1992 Olympic women's 2- champs) on people
who row a lot of pairs suggests that the stroke (whether on the left
or right) has to have a quicker uptake to peak force than bow, to
overcome bow's leverage advantage at the catch - the bow seat (again,
what ever side they're on) benefits by having a slightly later peak
force.- Hide quoted text -
- Show quoted text -

In that same vein, if you are ever going to race with a rudder --
which you will -- you should probably use it all the time. If you are
just learning to row a pair a rudder would just give you one more
thing to think and is probably unnecessary initially but should be
added later.

KC's suggestion of 'several weeks' is pretty reasonable. Many pairs
race at US trials having only rowed a pair for several weeks together
at best.

This is not something the US should be proud of BTW.

Post by kc
My method for coaching pairs is that they don't get a rudder until they
are rowing & racing at an elite or close to elite level. & even then
they'd need & get lots of practice time w/ the rudder. I've coached some
relatively successful pairs, and they have never raced with a rudder (nor
have I when I rowed & raced a pair) and they had some pretty intense final
250 meters in several races. But with communication and maturity, they
were all able to handle those situations fine and remained on course and
made some fantastic moves.

So much depends on the level of the athlete, and situations.

If a crew is good enough to go down the course without a
rudder, they are likely to be good enough to go down
the course and not use it.


snip

Post by kc

Post by ben
The other thing, from a practical point of view, is that there are two
times when you will unpredictably go off course -- the start and the
finish. Despite rowing with the same partner for hundreds and
hundreds of hours, we would still get slightly off course in the first
20 or the last 20 strokes about 1/3 of the time. This was quite
easily corrected with just a hint of rudder, which we otherwise hardly
used in a race, maybe four or five times down the course. I can't
imagine what it would be like to actually ease off at these times as
it would certainly throw off your balance a bit and particularly the
rythm. Even if you really practiced it, my feeling is that the easing
off or the going in a little early would affect the run of the boat

That's your feeling - but you are biased, for you did your pair rowing
with a rudder. I've never used one, and my crews never have, and thus my
"feeling" is the opposite. I've never had, nor have my crews, this
terrible problem you predict at the start or the finish. It's all about
maturity, knowing your partner, and communication.

Done both, coached both. When ben raced, he won the ltwt worlds
but didn't race any toe-less boats, nor did he try racing without.

It's not a good sample. Your question
challenges the status quo that 2- should be toed.

The example of the double earlier mentioned is a good one. Doubles
don't use toes, neither do quads.

Post by kc
This sounds like marriage counseling. ;^) But it's the truth, if you
know and trust your partner, and you know your and his limitations, then
you can predict what's going to happen & deal with it. If you have enough
race experience, then you are even that much more prepared. Each rower
has to have the maturity to either (a) back off when needed, or (b) ask
the other to back off if needed, and not get all mental about it.

It's little different than a situation where a partner feels the other is
using
the toe against them.

snip

Post by kc
To the best of my knowledge, every USA Oly M2- before 1972 rowed a Pocock
without a rudder, and many of them won.

1956 was the last gold, and prolly the last toe-less Oly champ.

Hough/Johnson won silver in toed stampfli in '68 as did Coffee/Staines in
'72.

The last Pocock that I can think of in an Oly regatta was 1964, the pair
with.

I have a lot of experience w/ coaching and rowing both toed/un-toed boats.
I'm with KC on the general approach. Teach ppl to race w/o toe, add it
to learn how to do it, use if needed. From a practical matter it works
pretty
well from my out of date, antiquated, out of touch, ancient delusional
experience.

JD and I won a nat'ls 2- in 1972 toeless, but while he pulled me into the
wall at the finish
right in front of John B' Kelly's likeness, making me cry like a little
bitch
to "ease up or I won't be your best man someday" I swear to this day it
was because he got to rest on the Schuylkill dogleg. We beat the toes!!!

We didn't go very straight, but then again when we finished 3rd in Sr Pair
at Canadian Henley in '73 with a toe we didn't go very straight either....

We stayed in our lane.

This doesn't prove anything, but I don't care....

:^)

[t***@gmail.com]

KC:
I postulate that showing a little of the side of the boat to the
finish line on each stroke is impossible to eliminate and go fast.
Here's the Athens final.
http://www.row2k.com/video/view.cfm?vid=4650
Ginn and Thomkins at 1:40. You can see the wag and it appears to me
they are on the rudder to compensate.
The Croates at 3:45. 2nd place, and have a tremendous amount of wag.
The Kiwis (4th) at 4:35. Wag

Two rowers with the same style or power curve will give the boat that
tail wag. When bow's blade enters the water, it is closer to the bow
of the boat than the stroke's, giving bow a mechanical advantage over
stroke. At the finish, stroke's is closer to the stern, giving stroke
the advantage, hence the tail wag, back and forth, each stroke. To go
perfectly straight, the stroke would have to have a very effective
catch and bow would have to have a whopper back half. I don't see the
benefit in teaching two styles of rowing in one boat. Wag in a 2- is
fact of life and a balancing out of the wag is one factor in a good
relationship between the rowers. It is the balance, not elimination of
wag, that allows for staying off the tiller. I believe that a good
pair is first and foremost a natural match with talented athletes who
have boat feel. I have always stipulated that rowing bow in a pair is
the hardest job in sweep, which is why I loved having Sully as bow
man. I just rowed as hard and well as I could and he did the
difficult part.
-JD

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without.  Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit.  But I've not done any actual analysis of the problem.  With older
less efficient rudders, it was obvious.  But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached.  I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course.  This also just
seems less efficient to me.  So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best.  But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

[z***@zekehoskin.com]

Post by KC
Carl, since you designed the aerowfin rudder/skeg system, you've
apparently put some decent amount of thought into this.
I often find myself disputing the claim that a pair is faster with a
rudder than without.  Many people seem to think that if one person is
slightly stronger, it's better to let them row all out and apply a
little rudder than to row sans rudder and force said rower to back off a
bit.
My analytical intuition says that it would always be faster to row such
that you don't need a rudder, even if that means one person backs off a
bit.  But I've not done any actual analysis of the problem.  With older
less efficient rudders, it was obvious.  But with a highly efficient
hydro-lifting rudder, I wonder if it's less clear cut now.
So I'm curious what you would say.
All of this is assuming no wind, no current, just less than perfectly
matched rowers trying to make a pair go straight.
IME, I've always removed rudders from all pairs I've used or coached.  I
think rowers learn to row better that way.
Also, while a rudder is good in a steady cross-wind (set it and forget
it) with one rower over powering the other, you'd have to constantly
have the rudder on then off, then on, then off, etc., so as not to turn
during the recovery.
Or, you find a setting that allows you to keep it on, and you just live
with a little fish-tailing, but a net straight course.  This also just
seems less efficient to me.  So long as the stronger rower is mentally
able to do it, I would think having him back off to match his partner
would be best.  But I'm surprised how many people disagree.
So is there any advantage (physically not psychologically) to allowing
the stronger rower to row all out, and using a highly efficient rudder
to compensate?
-KC

Since nobody else has mentioned this yet . . .
turning moment = force * length. Give the weaker rower a longer oar,
keeping the gearing the same. Whether or not you have a rudder, it
must be better to have a boat that wants to go straight.

[m***@googlemail.com]

On the grounds that this post might attract the pairing fraternity by
dint of it's title, has anyone any recommendations to make as regards
mirrors or other devices for letting you keep any eye on what's going
on in front of (that is, of course, behind!) you?

We pair on - as someone has pointed out - the twisty Cam, and have no
wish to turn a near miss into a direct hit!