Narrative:

Atl center cleared me to 6000 ft and switched me to atl approach. I gave my call sign and said descending to 6000. About 6500 and in 500 FPM descent, a passenger asked if I would call ahead to FBO to confirm rent-a-car would be waiting. It took a while to find arinc frequency and I did not notice passing 6000 ft. About 5200 atl approach called to tell me I was assigned 6000. It didn't seem (at the time) odd to be leveling at 5000. I was sure I had been cleared to 5000. I think in my mind the process of looking up the arinc I had arbitrarily assumed I could get the information written the min I had left. When I next looked up to the altimeter and received atl approach's query it seemed logical to be leveling at 5000. Further conversation with atl: approach asked if center had assigned me 5000 and I said yes. To prove this to myself I looked down to the altitude alerter and was dismayed to see 6000. I then realized my error and admitted to atl approach 'it may be my mistake.' I asked if he wanted me to climb to 6000. He said no, that 5000 was ok and cleared me direct to the airport. Compounding my not seeing the altitude alerter was a newly installed cup-holder making it difficult to read. I do not recall hearing the beep normally associated with the alerter either. I have removed the cup-holder. In conversation with the chief pilot about this situation, we have decided to minimize attempts at checking for rent-a-cars etc, especially in a busy environment.

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Original NASA ASRS Text

Title: ALTDEV ALT OVERSHOT IN DSCNT.

Narrative: ATL CTR CLRED ME TO 6000 FT AND SWITCHED ME TO ATL APCH. I GAVE MY CALL SIGN AND SAID DSNDING TO 6000. ABOUT 6500 AND IN 500 FPM DSCNT, A PAX ASKED IF I WOULD CALL AHEAD TO FBO TO CONFIRM RENT-A-CAR WOULD BE WAITING. IT TOOK A WHILE TO FIND ARINC FREQ AND I DID NOT NOTICE PASSING 6000 FT. ABOUT 5200 ATL APCH CALLED TO TELL ME I WAS ASSIGNED 6000. IT DIDN'T SEEM (AT THE TIME) ODD TO BE LEVELING AT 5000. I WAS SURE I HAD BEEN CLRED TO 5000. I THINK IN MY MIND THE PROCESS OF LOOKING UP THE ARINC I HAD ARBITRARILY ASSUMED I COULD GET THE INFO WRITTEN THE MIN I HAD LEFT. WHEN I NEXT LOOKED UP TO THE ALTIMETER AND RECEIVED ATL APCH'S QUERY IT SEEMED LOGICAL TO BE LEVELING AT 5000. FURTHER CONVERSATION WITH ATL: APCH ASKED IF CTR HAD ASSIGNED ME 5000 AND I SAID YES. TO PROVE THIS TO MYSELF I LOOKED DOWN TO THE ALT ALERTER AND WAS DISMAYED TO SEE 6000. I THEN REALIZED MY ERROR AND ADMITTED TO ATL APCH 'IT MAY BE MY MISTAKE.' I ASKED IF HE WANTED ME TO CLB TO 6000. HE SAID NO, THAT 5000 WAS OK AND CLRED ME DIRECT TO THE ARPT. COMPOUNDING MY NOT SEEING THE ALT ALERTER WAS A NEWLY INSTALLED CUP-HOLDER MAKING IT DIFFICULT TO READ. I DO NOT RECALL HEARING THE BEEP NORMALLY ASSOCIATED WITH THE ALERTER EITHER. I HAVE REMOVED THE CUP-HOLDER. IN CONVERSATION WITH THE CHIEF PLT ABOUT THIS SITUATION, WE HAVE DECIDED TO MINIMIZE ATTEMPTS AT CHKING FOR RENT-A-CARS ETC, ESPECIALLY IN A BUSY ENVIRONMENT.

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.