Narrative:

I was cleared through class B direct to a hospital and assigned 6000 ft. I looked down for a map, looked up seconds later and was at 6200 ft. I immediately returned to 6000 ft. ZZZ tower made no comment and handed me over to ZZZ approach. B407 requires constant attention to maintain altitude. I should not have looked away for a map in class B.

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Original NASA ASRS Text

Title: A BELL 407, EMS PLT HAS AN ALT EXCURSION IN A CLASS B AIRSPACE WHILE LOOKING FOR HIS NAV MAP.

Narrative: I WAS CLRED THROUGH CLASS B DIRECT TO A HOSPITAL AND ASSIGNED 6000 FT. I LOOKED DOWN FOR A MAP, LOOKED UP SECONDS LATER AND WAS AT 6200 FT. I IMMEDIATELY RETURNED TO 6000 FT. ZZZ TWR MADE NO COMMENT AND HANDED ME OVER TO ZZZ APCH. B407 REQUIRES CONSTANT ATTN TO MAINTAIN ALT. I SHOULD NOT HAVE LOOKED AWAY FOR A MAP IN CLASS B.

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.