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For decades, the has been a cornerstone of the general aviation panel. As the primary attitude indicator for the KCS 55 and KCS 55A compass systems, this 2-inch, remote-mounted vertical gyro provides pitch and roll data to flight instruments and autopilots like the KAP 150 and KFC 200.
Use shielded twisted-pair wire (MIL-W-22759 or equivalent) for all AC outputs and flight director signals. ki 256 installation manual
8.14 inches (20.68 cm) including connectors Weight: 3.4 lbs (1.54 kg) Mounting: Standard 3-inch ATI panel cutout Electrical Power For decades, the has been a cornerstone of
Apply 28V DC and 115V AC. Allow 3 minutes for spin-up. Depress the “CAGE” button on the KCS 55 controller for 10 seconds. The removal and installation of the KI 256
The removal and installation of the KI 256 follow standard procedures for face-mounted instruments:
| Symptom | Possible Cause | Remedy | | :--- | :--- | :--- | | KI‑256 remains caged or flags visible | Insufficient vacuum/pressure | Check vacuum gauge, filter, and hoses for leaks or blockages | | Attitude display sluggish or precesses | Low gyro speed (vacuum too low) or worn gyro bearings | Measure vacuum at instrument; overhaul the gyro if below spec | | Flight director command bar does not move | Missing or incorrect signals from autopilot computer; wiring fault | Check continuity of pins 3‑6; verify autopilot computer is powered and in active mode | | Autopilot hunts or oscillates in pitch | Pitch pick‑off mis‑calibrated or noisy output | Repeat pitch calibration; check shielding and grounding | | Roll angle flown is too high or too low | Roll pick‑off output level incorrect | Adjust series inductance as described in Section 5.3; verify roll calibration | | Bar oscillates or shimmies continuously | Insufficient vacuum; defective instrument; loose instrument in panel | Tighten mounting screws; measure vacuum; replace instrument if internal damping failed |
