COMPASS TURNS
The use of gyroscopic heading indicators make heading control very easy. However, if the heading indicator fails or your helicopter does not have one installed, you must use the magnetic compass for heading reference. When making compass-only turns, you need to adjust for the lead or lag created by acceleration and deceleration errors so that you roll out on the desired heading. When turning to a heading of north, the lead for the roll-out must include the number of degrees of your latitude plus the lead you normally use in recovery from turns. During a turn to a south heading, maintain the turn until the compass passes south the number of degrees of your latitude, minus your normal roll-out lead. For example, when turning from an easterly direction to north, where the latitude is 30°, start the roll-out when the compass reads 037° (30° plus one-half the 15° angle of bank, or whatever amount is appropriate for your rate of roll-out). When turning from an easterly direction to south, start the roll-out when the magnetic compass reads 203° (180° plus 30° minus one-half the angle of bank). When making similar turns from a westerly direction, the appropriate points at which to begin your roll-out would be 323° for a turn to north, and 157° for a turn to south.
 

COMMON ERRORS DURING TURNS
1 Failure to maintain desired turn rate.
2 Failure to maintain altitude in level turns.
3 Failure to maintain desired airspeed.
4 Variation in the rate of entry and recovery.
5 Failure to use proper lead in turns to a heading.
6 Failure to properly compute time during timed turns.
7 Failure to use proper leads and lags during the compass turns.
8 Improper use of power.
9 Failure to use proper pedal trim.

UNUSUAL ATTITUDES
Any maneuver not required for normal helicopter instrument flight is an unusual attitude and may be caused by any one or a combination of factors, such as turbulence, disorientation, instrument failure, confusion, preoccupation with cockpit duties, carelessness in cross-checking, errors in instrument interpretation, or lack of proficiency in aircraft control. Due to the instability characteristics of the helicopter, unusual attitudes can be extremely critical. As soon as you detect an unusual attitude, make a recovery to straight-and-level flight as soon as possible with a minimum loss of altitude.