No Checklist For This

I was flying a 2002-model A36 Bonanza (yeah, with me its always a Bonanza) home to Wichita from Thanksgiving in Ohio with my wife and our son aboard. Somewhere over Indiana, the Bonanzas attitude indicator (AI) began to tumble. The failure announced itself slowly, but very soon the instrument was pitching up and down in very distracting oscillations. It then displayed a range of indications-from off-scale nose-up pitch excursions to slightly below 20 degrees nose-down-in a roughly two-second cycle, while indicating bank angles between wings-level and about 10 degrees left.

Tom Turner

Wednesday, January 02, 2019 at 12:00 AM ET

Verified

Key Takeaways:

Upon an attitude indicator (AI) failure, immediately focus on maintaining aircraft control with gentle inputs, identify and confirm the failure by cross-referencing other instruments, and cover the distracting AI.
Prioritize using available backups, understanding your autopilot's failure modes (especially if it's rate-based and might remain functional), and transitioning to or remaining in Visual Meteorological Conditions (VMC).
Effective preparation is crucial: regularly practice partial-panel flight, know your aircraft's instrument power sources and autopilot interfaces, and commit to memory key power/attitude settings for various flight phases.
Always perform thorough pre-flight instrument checks and keep instrument covers (like sticky notes) readily accessible to manage failures calmly.

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I was flying a 2002-model A36 Bonanza (yeah, with me it’s always a Bonanza) home to Wichita from Thanksgiving in Ohio with my wife and our son aboard. Somewhere over Indiana, the Bonanza’s attitude indicator (AI) began to tumble. The failure announced itself slowly, but very soon the instrument was pitching up and down in very distracting oscillations. It then displayed a range of indications—from off-scale nose-up pitch excursions to slightly below 20 degrees nose-down—in a roughly two-second cycle, while indicating bank angles between wings-level and about 10 degrees left.

Although indications began slowly, I immediately knew something was wrong because the airplane’s KFC225 autopilot—which references the AI—disconnected as soon as the instrument’s gyroscope lost stabilization. Although the flight director command bars remained elevated (making it look like the autopilot might still be operating), the autopilot disconnected. The autopilot’s annunciator flashed a few times, then extinguished and the autopilot disconnect horn chirped.