INSTRUCTIONS FOR USE SEE DIAGRAM:
A : Place of setting heading
B : Destination
C : A "fix" right of intended track.
DGMPLE: The intended track was from A (Wyngan) to B (Lightning Ridge) a distance of 132 n.m. A "fix" was obtained at C (Carinda) right of intended track.
METHOD: To determine alteration to heading to fly direct to B, distance flown A to C and distance to flv C to B.

1. Place fi the centre of the base-line over the "fix" C, with the base-line connected to the place of setting heading A.

2. Note the RADIAL intercepting B. In this case by interpolating the 8" RADIAL. Therefore, the alteration to the present heading to fly direct to B (Lrghtning Ridgg) is 8" LEFT. Without moving the RULE from the above position:

3. The distance flown A to C, along the base-line, using the ARCS and interpolating is 70 n.m.

4. The distance to fly C to B, along the 8" RADIAL, again using the ARCS and interpolating is 62 n.m.

lf in the above example the "fix" had been LEFT of intended track then it would have been necessary to reverse the RULE and have the base-line to the LEFT.
TO DETERMINE TRACK ERROR: The track error is determined by placing the RULE with the centre of the base-line OVER THE Position oF SETTING HEADING and the base-line along intended track. The RADIAL which intercepts the "fix", interpolating if necessary, is the track error. In the above example the track error is 4'.

GROUND SPEED, TIME, DISTANCE COMPUTER : The central circular slide rule enables the pilot to solve problems involving time, speed and distance. The triangular index, A positioned at the "60 minute" graduation on the rotating scale, is known as the SPEED INDEX The outer fixed scale is known as the MILE SCALE and the inner rotatino scale the TIME SCALE.

On all ground speed, time, distance problems the SPEED INDEX is either opposite ground speed or will position itself opposite ground speed. Distance and time are always opposite each other.