19
Trimming Your Glider in Pitch
The fore and aft location along the keel of your hang point is commonly (if mistakenly) referred to as
your CG location. The location of this hang point will, all other things being equal, determine at
what angle of attack and airspeed your glider will naturally tend to fly (or trim), and therefore how
much bar pressure there is to pull in from trim to a given faster speed, or how much pressure there is to
push out from trim to a given slower speed. The farther forward your hang point is, the faster the glider
will trim, the less effort will be required to fly fast, and the more effort will be required to fly slow. If
your hang loop is too far aft, it will make the glider more difficult to control in roll, especially in
turbulent air and when the nose pitches up on entering a strong thermal.
On the Ultra Sport, hang loop fore and aft position is adjusted by repositioning the kingpost base
bracket in the keel mounted CG track. The bracket is secured by a clevis pin and safety ring. The
assembly is illustrated in the diagram
Ultra Sport Middle and Rear Keel
in the back of this manual.
We recommend that you not stow your glider bag, or any other cargo on the glider. The
practice of putting your glider bag inside the sail, for example, can drastically alter the
pitch trim and static balance of your glider, and adversely affect its flying and landing
characteristics. The best place to carry your glider bag or other cargo is in your harness.
In the absence of the use of tufts, it has become common for pilots to talk about bar position, or about
indicated airspeed, when trying to communicate how to trim a glider properly or how to fly a glider at
the proper speed for a given situation. The problem is that these methods are unreliable and inconsis-
tent from one pilot to another even on the same glider. The angle at which your harness suspends your
body in your glider has a great deal to do with your perception of the bar position relative to your
body. Airspeed indicators vary in their indicated airspeed depending on the make of the instrument, its
calibration, any installation error, etc. The use of tufts gives you an absolute first hand indication of the
actual aerodynamic event associated with two critically important airspeeds on your glider. It is a
potentially useful tool that may improve your flying.
Summary of Contents for Ultra Sport 135
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