User manual

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RMI-30 Radio Magnetic Indicator
1: VOR1 / ADF1 indicator needle
2: VOR2 / ADF2 indicator needle
3: VOR1 / ADF1 selector switch
4: VOR2 / ADF2 selector switch
5: HDG Warning Flag: Indicates a failure of
the gyro compass. This usually results
from the inverter not powering the gyro.
Course and heading information are sup-
plied to the RMI by the gyro compasses.
Inverter power is needed to operate the
SAS - Stability Augmentation System
(Cheyenne II only)
1: Stall Margin Indicator
A stability augmentation system (SAS) is
incorporated in the elevator control system
to improve the static longitudinal stability
of the airplane. Major components of
the SAS include an angleof-attack sensor
vane, a computer, servo actuator, and an
elevator down spring and cable assembly.
The angle-of-attack sensor vane, located
on the right side of the nose section,
transmits the airplane´s angle-of-attack to
the SAS computer.
Based on the input from the angle-of-attack sensor vane, the computer
sends a signal to the servo actuator, located in the aft fuselage of the
airplane, which is connected to the elevator control horn through the
elevator down spring and cable assembly. The servo actuator provides
variable elevator down spring tension improving the logitudinal stability
to allow more versatile loading.