Avian PUMA 13.5, Owner'S Manual

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Puma 13.5 Owner’s Manual
Trim speed
The trim speed is adjustable by moving the hang loop forwards or backwards along the keel. Forward
movement will speed trim the glider faster, whilst rearward movement will slow it down. Only move the hang
point in small increments (one hole at a time). The factory starting setting for the position of the hang point is
shown in Figure 5 on Page 31. It is important to adjust your glider to a trim speed that is safely above stall
speed and comfortable for you. (Trim speed is usually in the region of 24 mph on the Puma 13.5 but
remember your ASI may be calibrated differently to ours and how the glider flies is the important thing not
exactly what your ASI reads.)
Tuning out turns
If your glider will not fly straight in still air without constant pilot input then it is said to have a ‘turn’. If the
glider will fly straight but is easier to turn one way than the other then it has a ‘slight turn’.
Both are annoying and it is worth tuning your glider to fly without any preference to turn in one direction. It
is useful to note when the turn is most noticeable. For example does it get worse with the VG on full?
If your glider previously flew straight then the most likely explanation for the turn is that you have miss-
rigged or damaged your glider. Check the glider carefully when de-rigging to see if you can see any
problems. A compression strut not tensioned on one side would give a bad turn for example. Check the glider
visually first. Standing in front of the glider, holding by the nose wires to hold the glider level look at the
shape of the washout on the wing tips. You should be able to see an equal area and shape of washout on each
wing. Check with and without VG on.
If a turn is detected on a correctly rigged glider, first check the battens. Check them against each other
(making sure that they are the same on both sides) and then against the profile. Next check that the batten
tension is the same on both sides of the glider. (See Battens). If there is still a turn check that the leading
edges are straight and undamaged.
If the glider has a turn with the VG on full but flies straight with the VG off. Then the turn is likely to be due
to washout rod set up. A slight turn that gets much worse with the VG on full is also likely to be due to
washout rod set up.
A slight turn that only gets slightly worse with VG on may be tuned out using the adjustable tip caps. You
will require one 5mm Allen key.
The black plastic tip caps are infinitely adjustable. They have a line marked on them and there is another
line marked on the leading edge. These references are used for initial assembly (See STANDARD TIP CAP
SETTINGS page 34). The line on the leading edge is the datum.
To loosen the cap so that it can be turned insert the Allen key and turn anti-clockwise a couple of turns. If
the cap of the Allen key starts to protrude give the key a sharp knock which will push the cap screw in. Do
not loosen too much. It should now be possible to turn the tip with a little effort (the tension of the sail is still
pulling the cap tight into the leading edge). When the tip is in the desired position re-tighten the Allen screw.
Do not over tighten it.
The washout should only be adjusted in small increments (1mm at a time). The total movement should
NOT
exceed 10mm each side of the datum.
Which way to adjust the tip caps?
The wing that is lifting should have the washout increased (i.e. trailing edge lifted) while the wing dropping
should have the washout reduced (i.e. trailing edge lowered). Mark the leading edge with a pencil before
loosening the 5mm Allen screw so you know where you started. Make the adjustment and fly to check the
result. If large adjustments are required it is very likely that the glider is damaged in some other way and a
thorough examination or better still full strip-down inspection is recommended before further flight.
Puma 13.5 hand book-Rev-02 18