Narrative:

After receiving a clearance to depart class B airspace to the west, I took off and turned right to 240 degree heading and continued my climb. I had been cleared to 7000 ft and prior to reaching my altitude, I tried to call den departure 5 times unsuccessfully due to radio congestion. Initially I thought the problem may have been my radios so I tried a different radio and asked 'den departure, how do you hear this radio?' they then answered 'loud and clear you are radar contact say altitude.' I responded my altitude which at the time may have been 8500 ft and climbing. Den departure responded with a 'roger.' as I climbed through 12000 ft, den departure came back and asked, 'say altitude you were cleared to.' at that point I realized I had only been cleared to 7000 ft. I responded by saying, 'I believe I was cleared to 7000 ft, I'm sorry I blew my altitude.' den departure's response was, 'it looks like you're on top of everything now anyways, so frequency change is approved and squawk VFR, good day.' in my opinion, I believe that the primary cause for violating airspace was my inattn to my altitude in my clearance. I thought I had been cleared to climb unrestr. Contributing factors were that they were not answering my radio calls initially, distracting me from my clearance to deal with my communications.

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Original NASA ASRS Text

Title: PLT OF A CORP SMT TURBOPROP OVERSHOT INITIAL CLB ALT IN A CLASS B AIRSPACE CLRNC DUE TO DISTR OF 1 OF THE 2 COM RADIO'S PROBS.

Narrative: AFTER RECEIVING A CLRNC TO DEPART CLASS B AIRSPACE TO THE W, I TOOK OFF AND TURNED R TO 240 DEG HDG AND CONTINUED MY CLB. I HAD BEEN CLRED TO 7000 FT AND PRIOR TO REACHING MY ALT, I TRIED TO CALL DEN DEP 5 TIMES UNSUCCESSFULLY DUE TO RADIO CONGESTION. INITIALLY I THOUGHT THE PROB MAY HAVE BEEN MY RADIOS SO I TRIED A DIFFERENT RADIO AND ASKED 'DEN DEP, HOW DO YOU HEAR THIS RADIO?' THEY THEN ANSWERED 'LOUD AND CLR YOU ARE RADAR CONTACT SAY ALT.' I RESPONDED MY ALT WHICH AT THE TIME MAY HAVE BEEN 8500 FT AND CLBING. DEN DEP RESPONDED WITH A 'ROGER.' AS I CLBED THROUGH 12000 FT, DEN DEP CAME BACK AND ASKED, 'SAY ALT YOU WERE CLRED TO.' AT THAT POINT I REALIZED I HAD ONLY BEEN CLRED TO 7000 FT. I RESPONDED BY SAYING, 'I BELIEVE I WAS CLRED TO 7000 FT, I'M SORRY I BLEW MY ALT.' DEN DEP'S RESPONSE WAS, 'IT LOOKS LIKE YOU'RE ON TOP OF EVERYTHING NOW ANYWAYS, SO FREQ CHANGE IS APPROVED AND SQUAWK VFR, GOOD DAY.' IN MY OPINION, I BELIEVE THAT THE PRIMARY CAUSE FOR VIOLATING AIRSPACE WAS MY INATTN TO MY ALT IN MY CLRNC. I THOUGHT I HAD BEEN CLRED TO CLB UNRESTR. CONTRIBUTING FACTORS WERE THAT THEY WERE NOT ANSWERING MY RADIO CALLS INITIALLY, DISTRACTING ME FROM MY CLRNC TO DEAL WITH MY COMS.

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.