Wills Wing Sport 2 155, Owner'S Service Manual

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4" adjustments are available) or by shortening the tip wands. A one eighth of an inch difference (3mm)
in the length of the tip wand can make a noticeable difference in how a glider handles. If you have a
glider that is a little too stiff, you might try shortening the wands by an eighth inch.
You should also check the relationship between the tension is the sail mount strap at the aft end of the
leading edge, and the tension as taken by the tip wand. With the glider fully assembled, and the VG set
to full loose, the sail mount webbing strap at the rear end of the leading edge should be snug, but not
overly tight, and it should be symmetrical from side to side. It should then become progressively tighter
as the VG is engaged.
Twisting a tip
After you have made everything symmetrical, if you still have a turn, you can correct it by rotating one or
both tip wand receptacle end caps. A left turn is corrected by twisting the left sail plug counter clockwise
(twisting the tip wand down) or twisting the right sail plug counter clockwise (twisting the tip wand up)
or both, as indicated on the label attached to the rear leading edge. Twist clockwise on either or both
plugs to correct a right turn. Note that the mechanism of adjusting the sail wand receptacle for tuning out
a turn in the glider is the same as performing the same tuning function on a conventional tip, although the
direction of rotation seems to be opposite. For example, to remove a right turn, if working with the right
wing tip, you would rotate the end cap clockwise, so as to rotate the wand down, thus depressing the
right wing tip. On a conventional wingtip, you would rotate the end cap counter clockwise, because doing
so would rotate the wingtip downwards. The aerodynamic effect is the same, even though the direction
of rotation appears at first glance to be opposite. Adjustments are best made in one "notch" increments.
If you have rotated the right wing down both available notches, and still have a right turn, you can rotate
the left wing up.
To rotate the tip wand receptacle end cap, remove the securing screw, rotate the cap until you see the
next hole, then reinstall the screw.
Batten tension
The outboard most battens on each side are tensioned by looping the batten string over the notched end
of the batten twice. The remaining battens are all fitted with lever tips. The outboard batten with strings
should be adjusted quite tight for maximum sail cleanliness. On the battens fitted with lever tips, it is
important to adjust the lever tips to set the right batten tension. The lever action makes it easy to have
the battens set too tight. Batten tension is best judged by noting at what point the batten begins to
tension the sail as you pivot the lever tip down into its locked position. This is the point at which
chordwise slackness begins to be pulled out of the sail, the high point of the batten begins to make a
prominent ridge in the top surface, and a noticeable increase in resistance is felt in pivoting the tip
downwards. On any battens inboard of the crossbar junction, this point should not come until the lever
tip is within no more than the last 20 to 30 degrees of travel before becoming straight. On battens
outboard of the crossbar junction, this point should come when the lever is between 30 and 40 degrees
of straight. To lengthen the batten, simply unscrew the batten tip shank from the batten, to shorten the
batten screw the tip further in. Each three turns changes the length of the batten by 1/8 of an inch.