RE: [Paddlewise] Comparing sweeps chine and round hull - 'inertial' vs 'damped' responses

Some of the comments Matt made:
>SNIP I suspect turning into the wind you are willing to lean further to the

>inside (and into the wind) while low bracing on a reverse sweep than you
are
>willing do to the outside (leaning downwind) doing a forward stroke.
Turning 
>downwind you are in the opposite situation where you get to lean into the
wind 
>with the outside lean and must lean downwind doing a reverse sweep. Since
you 
>naturally lean into a wind some to compensate for the wind strength (to 
>maintain balance) you aren't so far off balance when leaning into the wind 
>than when leaning at an equal angle downwind.

>SNIP With forward speed an outside lean with a forward stroke is most
effective in
>turning a wider kayak (and most kayaks) into a wind because maintaining
speed
>means you are being helped by the weathercocking tendency and for an equal
>lean angle the stern keel will shed water better when the kayak is tilted
to
>the outside. You also gain the advantage of the side "lift" I talked about
>earlier helping drive the turn.

>SNIP Everybody should practice fast outside lean turns while maintaining
good
>bracing. The reason is that when the wind is strong you might still be able
to
>turn into it if you are willing to tilt the kayak away from the wind but
might
>not be able turn into the wind at all if you are afraid to tilt the kayak
that
>way. Practice this in strong winds when in a safe place. Being able to turn
>into a stronger wind can be a real safety advantage. At speed, most sea
kayaks
>can turn nearly twice as fast with a good outside lean as they can with the
>kayak level. 


G'Day,

Thanks Matt for the interesting post. Some of your points caught me by
surprise! Your point about the tendency to lean into or against the wind
sounds very likely though I have yet to check it. On Saturday the winds were
fluky, about 20-25knots blowing off shore with short period wind waves and
rebound. We had to stay near the cliffs so as not to be blown out to sea. So
very little wind sheltering behind cliffs and about 18knots surface wind
crossing bays near the beach and rounding points. I found it hard to
experiment and had to trust to reflex reactions. I'll try your suggestions
when it's about 15 knot surface wind with sub 1m waves, and/or long period
swell. 
 
I tested as much as I could in a sheltered spot. You're right about the
comfort factor comparing forward and reverse sweeps although it worked in
reverse for me and I was more hesitant with my port reverse sweep and very
comfortable with the forward sweeps. This is due to paddling with people who
are stronger and in faster, ruddered boats when I can't afford the drag
associated with reverse sweeps and practise forward sweeps often. Also I try
to focus on edging rather than leaning to get the hull further over (and
after years of being trashed in the surf).

When the Pittarak has very little load apart from my 70kg weight it goes
beyond its stable point with the cockpit rim edged to the water line and the
deck at about 45 degrees to the water surface. When using a forward sweep I
edge the cockpit rim about 1 cm below the water with some lift in the sweep
stroke. With a reverse sweep I edge the cockpit rim about 1cm above the
water line, i.e. a bit more hesitant! Larry Gray can take the Pittarak
almost to 90 degrees and seems to turn without any trouble at all in
conditions I'd find very challenging. He must be using a forward sweep with
a lot of lift, is that called a sculling sweep? I usually follow a forward
sweep with a slightly reduced edge, skimming the blade back across the water
in a low brace position trying not to touch the water but prepared to brace
if necessary. Likewise I return the reverse sweep by skimming the blade
forward above the water in a high brace position and with a slightly reduced
edge. In light winds and sea the Pittarak will turn on edge without any need
for a sweep stroke as per your weather cocking comment! All the sweep does
is make the turn faster. Taking advantage of this makes the boat a bit more
controllable in a following sea despite the weather cocking tendency,
otherwise in bigger following seas resorting to the skeg helps. 

Regarding your prediction on turning while moving. Its certainly less work
and a bit more stable than turning on the spot, as though the forward
movement is translating into a turning movement and contributing lift to the
forward sweep/scull stroke. So your comments about "weather cocking
tendency" and "side lift" seem to be right on the button. The comments on
safety were also useful, intrinsically and because sometimes I've found
paddlers not used to wind or following sea to be intimidated when turning
back. I'll remember your point when helping out, it will be a trade against
leaving them exposed for longer periods to beam seas and ease of turning in
a wide arc compared to on the spot. 

Thanks again - I'll provide some more pertinent feedback when I've tried
your suggestions and observations in wind.

All the best, PeterO
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