Narrative:

We had an FAA inspector in the jump seat giving us a line check. There was a line of thunderstorms just to the west of the field moving past rapidly. The ceiling was 500 ft with visibility 7 mi in rain. During descent, we briefed the approach to runway 1L, because we wanted the long runway due to rain. We were handed off to approach and received vectors to the ILS, which we assumed was the left. At about 8-10 mi out, the controller cleared us for the approach. I returned the radio call and switched to tower. I told tower we were joining the ILS to runway 1L. Tower said 'the right or left.' I said 'the ILS runway 1L approach.' at this time tower said 'roger, cleared to land runway 1L.' we landed and taxied to the gate. After engine shutdown, the FAA inspector asked if we were cleared for the ILS to runway 1L or runway 1R which we responded the ILS to runway 1L. The FAA inspector then checked the tapes and we were cleared for the ILS to runway 1R approach. At no time during the approach did the FAA inspector question our approach or clearance until we landed. At no time did approach or tower tell us we did something wrong. Due to WX and prebriefing to runway 1L we assumed our clearance was to the left. A proper readback of our approach clearance would have solved the problem with approach instead of waiting to clarify with tower. Although we were eventually cleared for the left and if we would have heard him clear us to the right, we would have asked for the left, we still did not think a violation was forthcoming.

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Original NASA ASRS Text

Title: B-737 FLC MAKES APCH TO WRONG RWY.

Narrative: WE HAD AN FAA INSPECTOR IN THE JUMP SEAT GIVING US A LINE CHK. THERE WAS A LINE OF TSTMS JUST TO THE W OF THE FIELD MOVING PAST RAPIDLY. THE CEILING WAS 500 FT WITH VISIBILITY 7 MI IN RAIN. DURING DSCNT, WE BRIEFED THE APCH TO RWY 1L, BECAUSE WE WANTED THE LONG RWY DUE TO RAIN. WE WERE HANDED OFF TO APCH AND RECEIVED VECTORS TO THE ILS, WHICH WE ASSUMED WAS THE L. AT ABOUT 8-10 MI OUT, THE CTLR CLRED US FOR THE APCH. I RETURNED THE RADIO CALL AND SWITCHED TO TWR. I TOLD TWR WE WERE JOINING THE ILS TO RWY 1L. TWR SAID 'THE R OR L.' I SAID 'THE ILS RWY 1L APCH.' AT THIS TIME TWR SAID 'ROGER, CLRED TO LAND RWY 1L.' WE LANDED AND TAXIED TO THE GATE. AFTER ENG SHUTDOWN, THE FAA INSPECTOR ASKED IF WE WERE CLRED FOR THE ILS TO RWY 1L OR RWY 1R WHICH WE RESPONDED THE ILS TO RWY 1L. THE FAA INSPECTOR THEN CHKED THE TAPES AND WE WERE CLRED FOR THE ILS TO RWY 1R APCH. AT NO TIME DURING THE APCH DID THE FAA INSPECTOR QUESTION OUR APCH OR CLRNC UNTIL WE LANDED. AT NO TIME DID APCH OR TWR TELL US WE DID SOMETHING WRONG. DUE TO WX AND PREBRIEFING TO RWY 1L WE ASSUMED OUR CLRNC WAS TO THE L. A PROPER READBACK OF OUR APCH CLRNC WOULD HAVE SOLVED THE PROB WITH APCH INSTEAD OF WAITING TO CLARIFY WITH TWR. ALTHOUGH WE WERE EVENTUALLY CLRED FOR THE L AND IF WE WOULD HAVE HEARD HIM CLR US TO THE R, WE WOULD HAVE ASKED FOR THE L, WE STILL DID NOT THINK A VIOLATION WAS FORTHCOMING.

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.