Narrative:

Holding at lendy intersection, autoplt attitude hold switch tripped off in turn. I (first officer) tripped autoplt off and climbed back to FL200. During recovery, center asked about altitude. 300 ft low. Captain was talking to dispatch at time of deviation. Maximum 300 ft deviation below altitude, momentarily.

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Original NASA ASRS Text

Title: ACR WDB HOLDING AT LENDY INTXN FL200, ALT HOLD SWITCH TRIPPED OFF RESULTING IN ALTDEV OF 300 FT, GOT 19700 FT. FO, PF, CORRECTED BACK TO ASSIGNED ALT. CAPT AND SO DISCUSSING FUEL REMAINING WITH DISPATCH.

Narrative: HOLDING AT LENDY INTXN, AUTOPLT ATTITUDE HOLD SWITCH TRIPPED OFF IN TURN. I (FO) TRIPPED AUTOPLT OFF AND CLBED BACK TO FL200. DURING RECOVERY, CTR ASKED ABOUT ALT. 300 FT LOW. CAPT WAS TALKING TO DISPATCH AT TIME OF DEV. MAX 300 FT DEV BELOW ALT, MOMENTARILY.

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.