Specifications

SECTION III
MODEL 560 INSTRUMENTATION AND AVIONICS
STANDBY FLIGHT DISPLAY
A Meggitt Avionics Standby Flight Display (SFD) System indicator is located on the left side of the
center instrument panel. This DC-powered cathode ray tube indicator combines standby attitude indicator,
and altimeter, and airspeed indications into one composite instrument. A Mach indication is also included in
the instrument. Pneumatics inputs, which are received from the standby pitot-static system, are fed into a
standby micro air data computer (MADC) which is powered from the DC emergency bus. The standby
MADC converts the data to digital information and forwards it to the indicator.
The SFD contains a gyro solid state inertial sensors for the measurement and presentation of aircraft
pitch and bank attitudes. Application of 28-volt DC power to the display system initiates the attitude
initialization process, which is identified by the display of the message “attitude initializing” in yellow on the
SFD. The duration of the initialization process is normally less than 180 seconds.
The attitude display has an instantaneous display range of 360° of bank and 50° of pitch. A moving
tape on the right side of the display includes a “rolling digit” depiction of altitude; the tape is marked in 100
foot increments with a numeric marking every 500 feet. The altitude display range is -2000 feet to 66,000
feet with a resolution of 20 feet. Baro data is set in the altitude display by a knob on the bottom right of the
bezel; clockwise rotation increases the pressure setting and counterclockwise decreases it. The setting is
displayed simultaneously in millibars at the top right of the display and in inches of mercury at the bottom
right. On the left side of the display is a moving tape showing airspeed. The tape is marked in ten knot
increments with a numeric marking every 20 knots and a “rolling digit” display in the center which becomes
active at 40 knots. The airspeed display range is 40 to 500 knots with a resolution of one knot. The Mach
number is displayed in the upper left corner of the display. The Mach display range is 0.350 to 0.999 Mach
with a resolution of 0.001 Mach.
Failure flag indications for airspeed and altitude are red crosses covering the appropriate tape box,
with all indications removed from within the box. The failure flags for the Mach indication and Baro Setting
are a series of four red dashes in the appropriate display area. A light sensor is located on the bottom left
side of the instrument case. It provides ambient light level data to the backlight control system to ensure
optimum display brightness. The lighting level can still be controlled manually from the center instrument
panel light rheostat control.
The navigation display is selected by the APR button on the bottom of the display bezel. Pressing the
button results in display of ILS localizer and glideslope information from NAV 1 receiver. The ILS can be
flown by reference to the ILS localizer and glideslope display on the SFD and/or standby horizontal situation
indicator (HSI).
Power to the SFD is controlled by a switch marked STDBY GYRO (ON)/OFF/TEST located on the
lower right of the pilot's instrument panel. The SFD has an emergency source of power from an
emergency battery pack located in the nose avionics compartment of the airplane. This battery pack also
provides emergency instrument lighting for the standby flight display system, the dual fan (N
1
)
tachometers/interturbine temperature (ITT) indicators and the standby horizontal situation indicator (HSI).
The battery pack is constantly charged by the airplane's electrical system, and should therefore be
fully charged in the event of an electrical power failure. The STDBY GYRO switch must be ON for
automatic transfer to battery power to occur. The SFD will operate for a minimum of 30 minutes on battery
power. An amber POWER ON light next to the STDBY GYRO switch illuminates when the SFD is turned
ON and the airplane's electrical system is not charging the emergency power supply batteries. When the
SFD switch is held to the spring-loaded TEST position, a self-test of the battery and circuits is
accomplished. The green GYRO TEST light, also next to the STDBY GYRO switch, will illuminate if the
test is satisfactory and the battery is sufficiently charged.
When NAV 1 is tuned for ILS operation, pressing the APR button will select ILS localizer and
glideslope display. Pressing the button a second time will provide back course display, and pressing it a
third time will revert the display to non-ILS format. Maximum allowable airspeed (VMO) is displayed in
analog form by a red warning strip on the airspeed tape. When VMO is reached, the numerals on the
numeric airspeed display change from white to red. When the maximum allowable Mach number (MMO) is
reached, the numeric Mach number display will also change from white to red.
I 56OMB-01 Configuration AA 3-13