The entire flight director/autopilot system is sometimes  called an integrated flight control system (IFCS) by some  manufacturers. Others may use the term automatic flight  control system (AFCS). The yaw damper is a servo that moves the rudder in response  to inputs from a gyroscope or accelerometer that detects yaw  rate. The yaw damper minimizes motion about the vertical  axis caused by turbulence. (Yaw dampers on swept wing  airplanes provide another, more vital function of damping  dutch roll characteristics.) Occupants feel a smoother ride,  particularly if seated in the rear of the airplane, when the yaw  damper is engaged. The yaw damper should be off for takeoff  and landing. There may be additional restrictions against its  use during single-engine operation. Most yaw dampers can  be engaged independently of the autopilot. The FD/AP system may be employed at the following  different levels: With the system off, the FCI operates as an ordinary attitude  indicator. On most FCIs, the command bars are biased out of  view when the FD is off. The pilot maneuvers the airplane  as though the system were not installed. To maneuver the airplane using the FD, the pilot enters the  desired modes of operation (heading, altitude, navigation  (NAV) intercept, and tracking) on the FD/AP mode  controller. The computed flight commands are then displayed  to the pilot through either a single-cue or dual-cue system  in the FCI. On a single-cue system, the commands are  indicated by “V” bars. On a dual-cue system, the commands  are displayed on two separate command bars, one for pitch  and one for roll. To maneuver the airplane using computed  commands, the pilot “flies” the symbolic airplane of the FCI  to match the steering cues presented. On most systems, to engage the autopilot the FD must first  be operating. At any time thereafter, the pilot may engage  the autopilot through the mode controller. The autopilot then  maneuvers the airplane to satisfy the computed commands  of the FD. Like any computer, the FD/AP system only does what it  is told. The pilot must ensure that it has been programmed  properly for the particular phase of flight desired. The  armed and/or engaged modes are usually displayed on the  mode controller or separate annunciator lights. When the  airplane is being hand-flown, if the FD is not being used at  any particular moment, it should be off so that the command  bars are pulled from view. Prior to system engagement, all FD/AP computer and trim  checks should be accomplished. Many newer systems  cannot be engaged without the completion of a self-test.  The pilot must also be very familiar with various methods  of disengagement, both normal and emergency. System  details, including approvals and limitations, can be found  in the supplements section of the AFM/POH. Additionally,  many avionics manufacturers can provide informative pilot  operating guides upon request. Inspection of the compartment interior is also an important  preflight item. More than one pilot has been surprised to find a  supposedly empty compartment packed to capacity or loaded  with ballast. The tow bars, engine inlet covers, windshield sun  screens, oil containers, spare chocks, and miscellaneous small  hand tools that find their way into baggage compartments  should be secured to prevent damage from shifting in flight. Most airplanes continue to fly with a nose baggage door open.  There may be some buffeting from the disturbed airflow, and  there is an increase in noise. Pilots should never become so  preoccupied with an open door (of any kind) that they fail  to fly the airplane. Nose baggage compartments are common on multiengine  airplanes (and are even found on a few single-engine  airplanes). There is nothing strange or exotic about a nose  baggage compartment, and the usual guidance concerning  observation of load limits applies. Pilots occasionally neglect  to secure the latches properly. When improperly secured, the  door opens and the contents may be drawn out, usually into  the propeller arc and just after takeoff. Even when the nose  baggage compartment is empty, airplanes have been lost  when the pilot became distracted by the open door. Security  of the nose baggage compartment latches and locks is a vital  preflight item. Alternator or generator paralleling circuitry matches the  output of each engine’s alternator/generator so that the  electrical system load is shared equally between them. In the  event of an alternator/generator failure, the inoperative unit  can be isolated and the entire electrical system powered from  the remaining one. Depending upon the electrical capacity  of the alternator/generator, the pilot may need to reduce the  electrical load (referred to as load shedding) when operating  on a single unit. The AFM/POH contains system description  and limitations. Alternator/Generator Nose Baggage Compartment Yaw Damper • Off (raw data) • Flight director (computed commands) •  Autopilot 12-7