G-Meter Another instrument that can be mounted in the instrument  panel of a glider is a G-meter. G-meters register positive G  forces from climbs and turns, as well as negative G forces  when diving down or pushing over from a climb. The G-meter  measures and displays the load imposed on the glider during  flight. During straight, unaccelerated flight in calm air, a  glider experiences a load factor of 1 G (1.0 times the force  of gravity). During aerobatics or during flight in turbulent  air, the glider and pilot experience G-loads greater than 1 G.  These additional loads result from accelerations imposed on  the glider. Some of these accelerations result from external  sources, such as flying into updrafts or downdrafts. Other  accelerations arise from pilot input on the controls, such as  pulling back or pushing forward on the control stick. G-loads  are classified as positive or negative. Positive G is felt when increasing pitch rapidly for a climb.  Negative G is felt when pushing over into a dive or during  sustained inverted flight. Each glider type is designed to  withstand a specified maximum positive G-load and a  specified maximum negative G-load. The GFM/POH is  the definitive source for this information. Exceeding the  allowable limit loads may result in deformation of the glider  structure. In extreme cases, exceeding permissible limit loads  may cause structural failure of the glider. The G-meter allows  the pilot to monitor G-loads from moment to moment. This  is useful in aerobatic flight and during flight in rough air.  Most G-meters also record and display the maximum positive  G-load and the maximum negative G-load encountered  during flight. The recorded maximum positive and negative  G-loads can be reset by adjusting the control knob of the  G-meter.  [Figure 4-31] Gyroscopic instruments are found in virtually all modern  airplanes but are infrequently found in gliders. Self-launching  gliders often have one or more gyroscopic instruments on  the panel. Gliders without power rarely have gyroscopic  instruments installed.  The three gyroscopic instruments found  most frequently in a glider are the heading indicator, attitude  indicator, and turn coordinator. Gyroscopic Instruments Figure 4-31.  The G-meter. Figure 4-30.  Left turn condition indications of a yaw string and  inclinometer. 30.0 29.9 29.8 I 0 0 F E T I 4 5 6 7 9 2 0 8 3 CALIBRATED TO  20,000 FEET ALT OFF GO L N AV NET AVG PULL PUSH HW DIST ALT PUSH 0 2 4 6 8 10 -2 -4 Acceleration UNITS N 30 60 E 120 150 STEER FOR S 210 240 W 300 330 STEER RADIO FOR ON ON 160 40 140 60 120 80 20 100 knots 0 2 2 4 4 6 6 8 8 10 10 knots winter 5 0 6 0  7 0  $_{ }$8 0  9 0 1 0 k n o t s $_{ }$S A L T O + − P WR FNCN SEL VOL BATT KNOTS PUSH 30.0 29.9 29.8 I 0 0 F E T I 4 5 6 7 9 2 0 8 3 CALIBRATED TO  20,000 FEET ALT OFF GO L N AV NET AVG PULL PUSH HW DIST ALT PUSH 0 2 4 6 8 10 -2 -4 Acceleration UNITS N 30 60 E 120 150 STEER FOR S 210 240 W 300 330 STEER RADIO FOR ON ON 160 40 140 60 120 80 20 100 knots 0 2 2 4 4 6 6 8 8 10 10 knots winter 5 0 6 0  7 0  $_{ }$8 0  9 0 1 0 k n o t s $_{ }$S A L T O + − P WR FNCN SEL VOL BATT KNOTS PUSH 30.0 29.9 29 .8 I 0 0 F E T I 4 5 6 7 9 2 0 8 3 CALIBRATED TO  20,000 FEET ALT OFF GO L N AV NET AVG PULL PUSH HW DIST ALT $^{PUS}$H 0 2 4 6 8 10 -2 -4 Acceleration UNITS N 30 60 E 120 150 STEER FOR S 210 240 W 300 330 STEER RADIO FOR ON ON 160 40 140 60 120 80 20 100 knots 0 2 2 4 4 6 6 8 8 10 10 knots winter 5 0 6 0  7 0  $_{ }$8 0  9 0 1 0 k n o t s $_{ }$S A L T O + − P WR FNCN SEL VOL BATT KNOTS PUSH Slip Coordinated Skid PUSH 0 2 4 6 8 10 -2 -4 Acceleration UNITS 4-17