KAP 150 KG 258 Alignment Question

[wingwalker63]

M20J w/ KAP 150 AP.  My KG 258 AI indicates 2 degree right bank when in straight/level flight.  Any guidance on procedure to re-align the instrument with roll axis of the aircraft appreciated.

Thank you

[Davidv]

Does this happen on the ground or just in flight?  

[wingwalker63]

The 2 degree discrepancy seems consistent both on the ground and in flight.  On the ground on a level surface the turn slip ball is centered but the AI indicates a right bank of about 2 degrees or so.  Thank you.

[N56394]

Perhaps try to swap in a loaner KG 258? Talk with Mid Continent or other Instrument shop? Could be simple calibration if off both on ground and in air but I think shop would need to make the adjustment. 

[Davidv]

I’d give Bob Bramble a call.  He’s been overhauling these for a long time and could tell you what the likely issue is and repair if need be.  I don’t have his number but should be easy to find online.

[wingwalker63]

Thank you for the help.  Talked to Bob Bramble.  Instrument is going out for evaluation and repair.

[PT20J]

The KAP 150 has gain adjustments for matching with the gyro. It might be good to check that whatever they do to the gyro shouldn't affect the autopilot. 

After you get it back if the airplane doesn't fly wings level (HDG and NAV off), there is a an adjustment hole in the front panel (toward the left side) for a mini blade screwdriver to adjust this.

When checking if the airplane is level, the official way is to put a level across the seat rails -- it's more accurate than the ball in the TC. You can tweak tire pressure to adjust if necessary.

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