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> Does  anyone know of a really good way of checking leeway?
>

Basically, it is the same as a set and drift problem. If I steer this
compass course, where will I actually wind up?  Sail between fixes and see
where you end up.

Current and drift are the gremlins in both the above (and compass variation
calculation).  If there is any set and drift, it will combine with leeway,
so you would have to back out set and drift to isolate the leeway component.

No current, boats compass deviation known:

Sail along a range line of known bearing. If there is any leeway, you will
have to "crab" to stay on the line. Note the difference between the compass
(corrected for deviation) and and the magnetic range course line.  The
difference should be leeway.

Another quick method is checking the angle of your wake compared to your
lubberline.

A poor man's set and drift method if unknown.  Take a stick about 3ft or
longer (wood batten?) and weight one end so only an inch or so is above the
water (won't catch wind or waves).  Plop it next to a buoy or mark.  Note
the direction and speed it moves away.  No buoy or mark?  Anchor a
balloon.--Buddy Melges

This is sort of intuitive for dingy racers.  One knows the wind direction
and close hauled directions, so pointing ability.  Try to round a mark a
distance off and dead ahead, and you will soon learn, seat of the pants,
what your leeway is.  When racing a Hobie 16, I know if I *really*  try to
pinch around a windward mark in a drifter, I can have over 30d leeway.  Bows
10 ft from the mark when directly upwind of the mark, and by the time the
mark is at my transom I am inches off it. That includes swinging the stern
away from the mark by turning.

Skirting trouble here, if you point your bowplate at an object with a known
bearing (compass) and compare that to a GPS track, that difference should
give you leeway.  (Nose on the target and compass will give you the
direction you are pointing, GPS will give you COG).  With a GPS with
compass it could get easier.

Bill


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