Narrative:

Work had just been done to tighten screws at collar where the yoke attaches to center post. Later discovered that the 4 screws for this are nonstandard and slightly long. It caused the aileron rod within this center post to be locked and I found myself with no aileron control. I declared an emergency and landed uneventfully at ZZZ1 airport, about 10 mi away. It's critical that these screws not be too long.

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Original NASA ASRS Text

Title: A BEECH A36 ON CLB AT 2500 FT DECLARED AN EMER AND DIVERTED DUE TO LOSS OF AILERON CTL CAUSED BY IMPROPER FASTENERS INSTALLED IN YOKE.

Narrative: WORK HAD JUST BEEN DONE TO TIGHTEN SCREWS AT COLLAR WHERE THE YOKE ATTACHES TO CENTER POST. LATER DISCOVERED THAT THE 4 SCREWS FOR THIS ARE NONSTANDARD AND SLIGHTLY LONG. IT CAUSED THE AILERON ROD WITHIN THIS CENTER POST TO BE LOCKED AND I FOUND MYSELF WITH NO AILERON CTL. I DECLARED AN EMER AND LANDED UNEVENTFULLY AT ZZZ1 ARPT, ABOUT 10 MI AWAY. IT'S CRITICAL THAT THESE SCREWS NOT BE TOO LONG.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.