Narrative:

On approach to pdx, we were on a vector of about 350 degrees and an altitude of 4000 ft. We were then cleared for the visual approach to runway 10L. As I began my descent, approach called and asked what our altitude was. The first officer responded with 3800 ft and approach then said we were supposed to be at 4000 ft and had not been cleared for the visual. I responded that I thought we had been (which I believe to be true) and approach then cleared us for the visual. No further items occurred relating to this flight. There wre no other conflicts. Supplemental information from acn 368337: pdx approach had cleared us from 5000 ft MSL to 4000 ft MSL and told us to expect the 'commuter visual' (local procedure for visual approach). Approach asked us to keep our best possible speed up for incoming traffic from the north and to continue toward the pwrlines. We then reported the field in sight and continued toward the pwrlines which put us on a right base to final to land on runway 10L. The captain began to descend toward the pwrlines, at 3800 ft MSL approach asked us our altitude and we said '3800 ft.' he then replied, 'I thought you were assigned 4000 ft' and we responded 'we thought we were clear for the commuter visual.' we thought we had been cleared for the commuter visual which meant we could descend to 2000 ft MSL until crossing the pwrlines.

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Original NASA ASRS Text

Title: BE1900 ASSIGNED 4000 FT TOLD TO EXPECT A VISUAL. CAPT THOUGHT HE WAS CLRED FOR A VISUAL AND GOT TO 3800 FT WHEN ATC CORRECTED HIM.

Narrative: ON APCH TO PDX, WE WERE ON A VECTOR OF ABOUT 350 DEGS AND AN ALT OF 4000 FT. WE WERE THEN CLRED FOR THE VISUAL APCH TO RWY 10L. AS I BEGAN MY DSCNT, APCH CALLED AND ASKED WHAT OUR ALT WAS. THE FO RESPONDED WITH 3800 FT AND APCH THEN SAID WE WERE SUPPOSED TO BE AT 4000 FT AND HAD NOT BEEN CLRED FOR THE VISUAL. I RESPONDED THAT I THOUGHT WE HAD BEEN (WHICH I BELIEVE TO BE TRUE) AND APCH THEN CLRED US FOR THE VISUAL. NO FURTHER ITEMS OCCURRED RELATING TO THIS FLT. THERE WRE NO OTHER CONFLICTS. SUPPLEMENTAL INFO FROM ACN 368337: PDX APCH HAD CLRED US FROM 5000 FT MSL TO 4000 FT MSL AND TOLD US TO EXPECT THE 'COMMUTER VISUAL' (LCL PROC FOR VISUAL APCH). APCH ASKED US TO KEEP OUR BEST POSSIBLE SPD UP FOR INCOMING TFC FROM THE N AND TO CONTINUE TOWARD THE PWRLINES. WE THEN RPTED THE FIELD IN SIGHT AND CONTINUED TOWARD THE PWRLINES WHICH PUT US ON A R BASE TO FINAL TO LAND ON RWY 10L. THE CAPT BEGAN TO DSND TOWARD THE PWRLINES, AT 3800 FT MSL APCH ASKED US OUR ALT AND WE SAID '3800 FT.' HE THEN REPLIED, 'I THOUGHT YOU WERE ASSIGNED 4000 FT' AND WE RESPONDED 'WE THOUGHT WE WERE CLR FOR THE COMMUTER VISUAL.' WE THOUGHT WE HAD BEEN CLRED FOR THE COMMUTER VISUAL WHICH MEANT WE COULD DSND TO 2000 FT MSL UNTIL XING THE PWRLINES.

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.