Narrative:

I was flying our company's second of 2 turbo small transport's. Aircraft Y was 10 NM ahead of me while we were trying to circumnav a large line of thunderstorms. The controller had just asked me how much farther on the current heading I was going to continue. I responded that I was in communication with aircraft Y and we were making a new plan. We decided to deviate to dbq and refuel. I asked the controller for direct dbq and lower. At the same time, the autoplt disengaged and I was pulling dbq from my plates. He cleared me direct dbq at 13000 ft. I responded that I was turning direct dbq descending to 13000 ft. A few mins later, a new controller came on frequency and asked where I was going. I told him direct dbq at 13000 ft. He was not the one that assigned it but wondered if I might have requested it under Y's number, who was not on the frequency yet but was doing the same thing 10 mi behind me. I was not sure at the time, due to the fact I was extremely busy. I had only 20 NM to get down from 220 was hand flying the airplane, pulling plates out, getting ATIS, and had just flown aircraft Y 2 days before. Aircraft numbers are close if you've been flying the other one the day before. I reported dbq in sight and requested a 360 degree turn to lose altitude. I was assigned 5000 ft but can't remember if I was cleared for the visual approach after reporting the airport in sight. A 360 was approved and I was switched to tower. There could be a possibility that I used aircraft Y's number when making my original request. Aircraft Y was 10 NM behind me and on a different frequency. I was very busy with all the things I had to do in preparation for landing including hand flying the airplane because the autoplt was inoperative. The controller told me this did not create a problem but a pilot should remember which airplane he's flying, especially when there are the same type and you actively fly them all.

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Original NASA ASRS Text

Title: HDG TRACK DEV AND ALTDEV ALT EXCURSION.

Narrative: I WAS FLYING OUR COMPANY'S SECOND OF 2 TURBO SMT'S. ACFT Y WAS 10 NM AHEAD OF ME WHILE WE WERE TRYING TO CIRCUMNAV A LARGE LINE OF TSTMS. THE CTLR HAD JUST ASKED ME HOW MUCH FARTHER ON THE CURRENT HDG I WAS GOING TO CONTINUE. I RESPONDED THAT I WAS IN COM WITH ACFT Y AND WE WERE MAKING A NEW PLAN. WE DECIDED TO DEVIATE TO DBQ AND REFUEL. I ASKED THE CTLR FOR DIRECT DBQ AND LOWER. AT THE SAME TIME, THE AUTOPLT DISENGAGED AND I WAS PULLING DBQ FROM MY PLATES. HE CLRED ME DIRECT DBQ AT 13000 FT. I RESPONDED THAT I WAS TURNING DIRECT DBQ DSNDING TO 13000 FT. A FEW MINS LATER, A NEW CTLR CAME ON FREQ AND ASKED WHERE I WAS GOING. I TOLD HIM DIRECT DBQ AT 13000 FT. HE WAS NOT THE ONE THAT ASSIGNED IT BUT WONDERED IF I MIGHT HAVE REQUESTED IT UNDER Y'S NUMBER, WHO WAS NOT ON THE FREQ YET BUT WAS DOING THE SAME THING 10 MI BEHIND ME. I WAS NOT SURE AT THE TIME, DUE TO THE FACT I WAS EXTREMELY BUSY. I HAD ONLY 20 NM TO GET DOWN FROM 220 WAS HAND FLYING THE AIRPLANE, PULLING PLATES OUT, GETTING ATIS, AND HAD JUST FLOWN ACFT Y 2 DAYS BEFORE. ACFT NUMBERS ARE CLOSE IF YOU'VE BEEN FLYING THE OTHER ONE THE DAY BEFORE. I RPTED DBQ IN SIGHT AND REQUESTED A 360 DEG TURN TO LOSE ALT. I WAS ASSIGNED 5000 FT BUT CAN'T REMEMBER IF I WAS CLRED FOR THE VISUAL APCH AFTER RPTING THE ARPT IN SIGHT. A 360 WAS APPROVED AND I WAS SWITCHED TO TWR. THERE COULD BE A POSSIBILITY THAT I USED ACFT Y'S NUMBER WHEN MAKING MY ORIGINAL REQUEST. ACFT Y WAS 10 NM BEHIND ME AND ON A DIFFERENT FREQ. I WAS VERY BUSY WITH ALL THE THINGS I HAD TO DO IN PREPARATION FOR LNDG INCLUDING HAND FLYING THE AIRPLANE BECAUSE THE AUTOPLT WAS INOP. THE CTLR TOLD ME THIS DID NOT CREATE A PROBLEM BUT A PLT SHOULD REMEMBER WHICH AIRPLANE HE'S FLYING, ESPECIALLY WHEN THERE ARE THE SAME TYPE AND YOU ACTIVELY FLY THEM ALL.

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.