There was some correspondence recently on the issue of
the F25 Mast Tiller.
There is reference to the “mast tiller” in the Freedom
Yachts “How to sail the Freedom 25” sheet which reads
as follows:-
Quote
To Trim Sail
Remember that the whole purpose of the rotating wing
mast is to allow the mast and the sail to form a
smooth airfoil. To accomplish this, the mast and boom
must be set at slightly different angles to the wind.
The mast is always trimmed to the wider angle, since
it is the leading edge of the airfoil.
By design, the mast will want to over-rotate and must
be restrained by the “mast tiller” which adjusts the
angle between the boom and the mast. The tiller
should be set so that the leeward side of the mast
flows fairly with the leeward side of the sail.
What we are looking for is attached air flow over both
sides of the sail. This can be checked by viewing the
ribbons on the sail through the plastic window. When
the ribbons are all streaming aft, you are getting
full efficiency.
Unquote
Owners with a “mast tiller”, who are perhaps unsure of
how to use it, may find that the easiest route is to
speak to a catamaran (Hobie; Prindle) sailor or to a
Tasar dinghy sailor since these small high performance
craft use a similar sounding device to fine tune the
mast/boom/sail profile.
Posted by Herman and Gail Schiller (hschiller2@…>)
When speaking with catamaran sailors, use “mast rotation limiter”
instead of “Mast Tiller” when referring to this technology. Herm
At 04:52 AM 5/31/2007, ABC wrote:
There was some correspondence recently on the issue of
the F25 Mast Tiller.
There is reference to the “mast tiller” in the Freedom
Yachts “How to sail the Freedom 25” sheet which reads
as follows:-
Quote
To Trim Sail
Remember that the whole purpose of the rotating wing
mast is to allow the mast and the sail to form a
smooth airfoil. To accomplish this, the mast and boom
must be set at slightly different angles to the wind.
The mast is always trimmed to the wider angle, since
it is the leading edge of the airfoil.
By design, the mast will want to over-rotate and must
be restrained by the “mast tiller” which adjusts the
angle between the boom and the mast. The tiller
should be set so that the leeward side of the mast
flows fairly with the leeward side of the sail.
What we are looking for is attached air flow over both
sides of the sail. This can be checked by viewing the
ribbons on the sail through the plastic window. When
the ribbons are all streaming aft, you are getting
full efficiency.
Unquote
Owners with a “mast tiller”, who are perhaps unsure of
how to use it, may find that the easiest route is to
speak to a catamaran (Hobie; Prindle) sailor or to a
Tasar dinghy sailor since these small high performance
craft use a similar sounding device to fine tune the
mast/boom/sail profile.