appropriate instruments, exert the necessary pressures to  move the ailerons and roll the aircraft about the longitudinal  axis. As illustrated in  Figure 6-11 , these instruments include: The altimeter is an important instrument for indicating pitch  attitude in level flight except when used in conditions of  exceptionally strong vertical currents, such as thunderstorms.  With proper power settings, any of the pitch attitude  instruments can be used to hold reasonably level flight  attitude. However, only the altimeter gives the exact altitude  information. Regardless of which pitch attitude control  instrument indicates a need for a pitch attitude adjustment,  the attitude indicator, if available, should be used to make  the adjustment. Common errors in pitch attitude control are: As previously discussed, the attitude indicator is the only  instrument that portrays both instantly and directly the actual  flight attitude and is the basic attitude reference. The heading indicator supplies the pertinent bank and heading  information and is considered a primary instrument for bank. The magnetic compass provides heading information and is  considered a bank instrument when used with the heading  indicator. Care should be exercised when using the magnetic  compass as it is affected by acceleration, deceleration in  flight caused by turbulence, climbing, descending, power  changes, and airspeed adjustments. Additionally, the  magnetic compass indication will lead and lag in its reading  depending upon the direction of turn. As a result, acceptance  of its indication should be considered with other instruments  that indicate turn information. These include the already  mentioned attitude and heading indicators, as well as the  turn-and-slip indicator and turn coordinator.  Bank control is controlling the angle made by the wing and  the horizon. After interpreting the bank attitude from the  •  Overcontrolling; •  Improperly using power; and •  Failing to adequately cross-check the pitch attitude  instruments and take corrective action when pitch  attitude change is needed. • Attitude indicator • Heading indicator • Magnetic compass • Turn coordinator/turn-and-slip indicator Figure 6-10.  Pitch attitude has moved higher. Attitude Indicator Heading Indicator Magnetic Compass Pitch Attitude Instrument Cross-Check Bank Control 3 0 W 2 4 Figure 6-11.  Bank instruments. 6-7