Narrative:

I arrived cid on an IFR flight plan from the south. I arrived in an small aircraft. My purpose for landing was to refuel. After refueling. I decided to depart VFR. The WX at the time was cavu. I called ground control and stated 'ncxxxx is ready for taxi, VFR departure northbound with current ATIS'. Ground control response was a taxi clearance to runway 13. This is a short taxi from the ramp. As I began taxiing, ground control came back with a surprise clearance to hold a 70 degree heading after departure, maintain 2500' and squawk a certain transponder code other than 1200 VFR. I was not expecting this clearance as I was departing VFR. I therefore hurriedly repeated the clearance as I was entering the code in the transponder. Thinking I was a VFR departure, I focused on heading and transponder code. The problem arose because ground control issued the clearance with no warning of a pending clearance, and I was not prepared to write out a clearance. If I was told 'clearance are you ready to copy?' I would have had a chance to set the parking brakes, find a pencil, and write down the clearance. After departure, while I was leveling at 6500' MSL, departure control asked my altitude. I responded with 'level at 6500'' . Departure advised me that I was only cleared to 2500' (this surprised me because the aircraft has a mode C altitude reporting transponder and departure should have noticed the altitude excursion earlier than 6500' level off). I stated I was a VFR departure northbound and he said 'maintain 6500''.

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Original NASA ASRS Text

Title: GA SMA ALT DEVIATION OVERSHOT DURING CLIMB OUT FROM CID ARSA.

Narrative: I ARRIVED CID ON AN IFR FLT PLAN FROM THE S. I ARRIVED IN AN SMA. MY PURPOSE FOR LNDG WAS TO REFUEL. AFTER REFUELING. I DECIDED TO DEPART VFR. THE WX AT THE TIME WAS CAVU. I CALLED GND CTL AND STATED 'NCXXXX IS READY FOR TAXI, VFR DEP NBOUND WITH CURRENT ATIS'. GND CTL RESPONSE WAS A TAXI CLRNC TO RWY 13. THIS IS A SHORT TAXI FROM THE RAMP. AS I BEGAN TAXIING, GND CTL CAME BACK WITH A SURPRISE CLRNC TO HOLD A 70 DEG HDG AFTER DEP, MAINTAIN 2500' AND SQUAWK A CERTAIN TRANSPONDER CODE OTHER THAN 1200 VFR. I WAS NOT EXPECTING THIS CLRNC AS I WAS DEPARTING VFR. I THEREFORE HURRIEDLY REPEATED THE CLRNC AS I WAS ENTERING THE CODE IN THE TRANSPONDER. THINKING I WAS A VFR DEP, I FOCUSED ON HDG AND TRANSPONDER CODE. THE PROB AROSE BECAUSE GND CTL ISSUED THE CLRNC WITH NO WARNING OF A PENDING CLRNC, AND I WAS NOT PREPARED TO WRITE OUT A CLRNC. IF I WAS TOLD 'CLRNC ARE YOU READY TO COPY?' I WOULD HAVE HAD A CHANCE TO SET THE PARKING BRAKES, FIND A PENCIL, AND WRITE DOWN THE CLRNC. AFTER DEP, WHILE I WAS LEVELING AT 6500' MSL, DEP CTL ASKED MY ALT. I RESPONDED WITH 'LEVEL AT 6500'' . DEP ADVISED ME THAT I WAS ONLY CLRED TO 2500' (THIS SURPRISED ME BECAUSE THE ACFT HAS A MODE C ALT RPTING TRANSPONDER AND DEP SHOULD HAVE NOTICED THE ALT EXCURSION EARLIER THAN 6500' LEVEL OFF). I STATED I WAS A VFR DEP NBOUND AND HE SAID 'MAINTAIN 6500''.

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.