Narrative:

I took off from gxy. Picked up IFR clearance en route 'as filed, climb and maintain 12000 ft.' was handed off to den approach with whom I checked in with. I don't remember telling the approach controller what altitude I was at or climbing to. I think it took a couple of calls to get a response from the controller. I continued on course. After a while the controller asked 'what altitude are you?' I said '13300 ft climbing to 15000 ft.' the controller said 'you are supposed to be at 12000 ft, maintain 13000 ft.' I descended to and maintained 13000 ft. I had filed for an altitude of FL180 and was climbing to it. I almost always check in with an altitude at and climbing to. I do have an altitude reminder flag on my altimeter that I will use faithfully.

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Original NASA ASRS Text

Title: A PVT INST RATED PLT DEPARTING GXY WAS ALERTED BY DEN APCH CTL THAT HE WAS CLBING ABOVE HIS ASSIGNED ALT AND GIVEN A NEW CLRNC.

Narrative: I TOOK OFF FROM GXY. PICKED UP IFR CLRNC ENRTE 'AS FILED, CLB AND MAINTAIN 12000 FT.' WAS HANDED OFF TO DEN APCH WITH WHOM I CHKED IN WITH. I DON'T REMEMBER TELLING THE APCH CTLR WHAT ALT I WAS AT OR CLBING TO. I THINK IT TOOK A COUPLE OF CALLS TO GET A RESPONSE FROM THE CTLR. I CONTINUED ON COURSE. AFTER A WHILE THE CTLR ASKED 'WHAT ALT ARE YOU?' I SAID '13300 FT CLBING TO 15000 FT.' THE CTLR SAID 'YOU ARE SUPPOSED TO BE AT 12000 FT, MAINTAIN 13000 FT.' I DSNDED TO AND MAINTAINED 13000 FT. I HAD FILED FOR AN ALT OF FL180 AND WAS CLBING TO IT. I ALMOST ALWAYS CHK IN WITH AN ALT AT AND CLBING TO. I DO HAVE AN ALT REMINDER FLAG ON MY ALTIMETER THAT I WILL USE FAITHFULLY.

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.