Narrative:

On approach; landing gear showed right main was not down and locked. Began missed approach to run checklists to correct problem. On climb out; was assigned 4000 ft. Due to inattn; climbed to 4500 ft before stopping climb. Controller brought deviation to our attention; at which point we descended to 4000 ft as assigned.

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Original NASA ASRS Text

Title: A BE400 LNDG GEAR NOT DOWN WARNING CAUSED THE PLT TO MAKE A MISSED APCH. DISTRACTED; THE PILOT CLBED TO 4500 FT WHEN 4000 FT WAS ASSIGNED; CAUSING AN ALT DEV.

Narrative: ON APCH; LNDG GEAR SHOWED R MAIN WAS NOT DOWN AND LOCKED. BEGAN MISSED APCH TO RUN CHKLISTS TO CORRECT PROB. ON CLBOUT; WAS ASSIGNED 4000 FT. DUE TO INATTN; CLBED TO 4500 FT BEFORE STOPPING CLB. CTLR BROUGHT DEV TO OUR ATTN; AT WHICH POINT WE DSNDED TO 4000 FT AS ASSIGNED.

Data retrieved from NASA's ASRS site as of May 2009 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.