: Post-installation alignment involves placing the unit on a tilt stand and adjusting zero-adjust and gain-adjust potentiometers while monitoring voltages on specialized test sets like the Replacement Limitations
The official installation manual is typically:
The KI 256 is designed to work with BendixKing's KFC-150, KFC-200, KFC 225, and KFC 250 Flight Control Systems. It can be integrated with King's KTS 150 Autopilot Test Set, a specialized tool placed in series with the autopilot computer and aircraft harness. During calibration, the KI 256 is placed on a gyro test stand for precise gyro and computer calibration.
The removal and installation of the KI 256 follow standard procedures for face-mounted instruments: ki 256 installation manual
: Functions as a standard primary attitude indicator and a flight director with a single-cue command bar.
Whether you’re a weekend warrior or a career avionics technician, keep a copy of in your hangar library. Your autopilot will thank you.
Follow the specific wiring diagram found in the KFC 150/200/225 installation manuals . Connector Mapping: Typical connections include: Power: 14V14 cap V 28V28 cap V DC depending on the unit variant. Gyro Power: 26VAC26 cap V cap A cap C 400Hz400 cap H z for the gyro motor. Attitude Data: Signals to the pitch and roll computers. Command Bars: Signals from the computer to the display. 4. Post-Installation Testing and Calibration : Post-installation alignment involves placing the unit on
: Connect a clean, regulated air source to the intake port at the rear. Use approved flexible hoses that accommodate minor instrument panel vibration without placing stress on the instrument fittings. Electrical Wiring & Pin Interfaces
Ensure the instrument panel is clean and the hole is cut to standard dimensions.
14 VDC or 28 VDC (Internal lighting configuration depends on the specific dash number) The removal and installation of the KI 256
: Accepts DC drive currents from the computer to steer the single-cue command bars dynamically over the attitude horizon.
The KI 256 uses a standard dual-row edge connector or a high-density circular plug depending on the modification status. Below is the standard pinout configuration for the autopilot interface signals. Pin Identifier Signal Name Function Description Gyro Common Ground reference for internal synchros Pin B Pitch Excitation 400 Hz AC input reference from autopilot Pin C Roll Excitation 400 Hz AC input reference from autopilot Pin D Pitch Pickoff Hi Pitch attitude error output signal Pin E Pitch Pickoff Lo Pitch attitude error return path Pin F Roll Pickoff Hi Roll attitude error output signal Pin G Roll Pickoff Lo Roll attitude error return path Pin H Flight Director Bar + Command bar upward deflection drive Pin J Flight Director Bar - Command bar downward deflection drive Pin K 28 VDC Lighting Panel backlight power supply Pin L Chassis Ground Airframe electrical ground connection Wiring Guidelines
