Narrative:

Time: XX15, ATC frequency 118.25 ATC facility, ny departure location: lga VOR 240 degree radial 14 mi on climb out of lga and while avoiding WX, with captain hand flying, aircraft was inadvertently climbed to 12400 ft when clearance was only to 12000 ft. Aircraft was immediately returned to assigned altitude. No mention was made by ATC. Flight continued without further incident.

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Original NASA ASRS Text

Title: ALTDEV. OVERSHOOT ON CLB BY 400 FT.

Narrative: TIME: XX15, ATC FREQ 118.25 ATC FACILITY, NY DEP LOCATION: LGA VOR 240 DEG RADIAL 14 MI ON CLB OUT OF LGA AND WHILE AVOIDING WX, WITH CAPT HAND FLYING, ACFT WAS INADVERTENTLY CLBED TO 12400 FT WHEN CLRNC WAS ONLY TO 12000 FT. ACFT WAS IMMEDIATELY RETURNED TO ASSIGNED ALT. NO MENTION WAS MADE BY ATC. FLT CONTINUED WITHOUT FURTHER INCIDENT.

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.