Narrative:

I was the PNF. Captain, PIC, departed srq for a repos for a passage flight out of bct. On departure, we were vectored to a 140 degree heading and an altitude of 10000 ft. We were further vectored to 180 degrees and given a climb to FL180. Our SOP calls for a checks and balance between crew members, as well as reading back all runway, heading, and altitude assignments. My first officer was hand flying. His concentration may have diverted his attention so that the confusion between what I thought I heard (a climb to FL180) was the vector heading only, and putting it into the altitude alerter should have met with a challenge if it wasn't what he heard. We switched over to center, and were unable to get a response for 3 attempts. The controller seemed to be fixated and saturated. Finally, at 163 degree vector, FL180, controller directed us to stop our climb at 16000 ft, talked to traffic above and behind us, gave us an immediate turn east, maintain 16000 ft. Having passed 16000 ft on the way for FL180, I helped the first officer return to the altitude. The remainder of the flight was typical. I was tracked down via company to call mia watch supervisor, which I did. He said there was no clearance to FL180. I said I heard it and read it back. Supplemental information from acn 498191: on a repos flight from sarasota to boca raton, fl, I was the pilot flying the aircraft. We were given a call from ATC and I was concentrating on flying the aircraft without the use of the autoplt. The PNF entered an altitude into the altitude alerter of FL180 and I began a climb to FL180. 1/2 way between 10000 ft and FL180, we were handed off to another center and were told to maintain 16000 ft after 3 attempts to check in. We were eventually given a heading to avoid traffic. Being I was concentrating on flying the aircraft, I should have verified the altitude change with the PNF or ATC before I began my climb. If I myself do not hear an altitude change from ATC, I will confirm it with ATC.

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Original NASA ASRS Text

Title: C650 CREW HAD ALT EXCURSION IN ZMA CLASS E AIRSPACE.

Narrative: I WAS THE PNF. CAPT, PIC, DEPARTED SRQ FOR A REPOS FOR A PASSAGE FLT OUT OF BCT. ON DEP, WE WERE VECTORED TO A 140 DEG HDG AND AN ALT OF 10000 FT. WE WERE FURTHER VECTORED TO 180 DEGS AND GIVEN A CLB TO FL180. OUR SOP CALLS FOR A CHKS AND BAL BTWN CREW MEMBERS, AS WELL AS READING BACK ALL RWY, HDG, AND ALT ASSIGNMENTS. MY FO WAS HAND FLYING. HIS CONCENTRATION MAY HAVE DIVERTED HIS ATTN SO THAT THE CONFUSION BTWN WHAT I THOUGHT I HEARD (A CLB TO FL180) WAS THE VECTOR HDG ONLY, AND PUTTING IT INTO THE ALT ALERTER SHOULD HAVE MET WITH A CHALLENGE IF IT WASN'T WHAT HE HEARD. WE SWITCHED OVER TO CTR, AND WERE UNABLE TO GET A RESPONSE FOR 3 ATTEMPTS. THE CTLR SEEMED TO BE FIXATED AND SATURATED. FINALLY, AT 163 DEG VECTOR, FL180, CTLR DIRECTED US TO STOP OUR CLB AT 16000 FT, TALKED TO TFC ABOVE AND BEHIND US, GAVE US AN IMMEDIATE TURN E, MAINTAIN 16000 FT. HAVING PASSED 16000 FT ON THE WAY FOR FL180, I HELPED THE FO RETURN TO THE ALT. THE REMAINDER OF THE FLT WAS TYPICAL. I WAS TRACKED DOWN VIA COMPANY TO CALL MIA WATCH SUPVR, WHICH I DID. HE SAID THERE WAS NO CLRNC TO FL180. I SAID I HEARD IT AND READ IT BACK. SUPPLEMENTAL INFO FROM ACN 498191: ON A REPOS FLT FROM SARASOTA TO BOCA RATON, FL, I WAS THE PLT FLYING THE ACFT. WE WERE GIVEN A CALL FROM ATC AND I WAS CONCENTRATING ON FLYING THE ACFT WITHOUT THE USE OF THE AUTOPLT. THE PNF ENTERED AN ALT INTO THE ALT ALERTER OF FL180 AND I BEGAN A CLB TO FL180. 1/2 WAY BTWN 10000 FT AND FL180, WE WERE HANDED OFF TO ANOTHER CTR AND WERE TOLD TO MAINTAIN 16000 FT AFTER 3 ATTEMPTS TO CHK IN. WE WERE EVENTUALLY GIVEN A HDG TO AVOID TFC. BEING I WAS CONCENTRATING ON FLYING THE ACFT, I SHOULD HAVE VERIFIED THE ALT CHANGE WITH THE PNF OR ATC BEFORE I BEGAN MY CLB. IF I MYSELF DO NOT HEAR AN ALT CHANGE FROM ATC, I WILL CONFIRM IT WITH ATC.

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.