Narrative:

Our aircraft was cleared for a visual landing on runway 19R at iad. On landing the tower controller said exit the runway on taxiway Y4 (that's what we heard first and read back to him). The controller then immediately said we were going the wrong way and to taxi to Y5. He had just cleared another citation for takeoff on runway 19R and in the confusion of which taxiway we were supposed to be on we may have not been across the active runway markings. We were not on the runway itself, but we are not sure if we had crossed the runway hold short line at that point. Since we had been given taxiway Y4 first we had to slow down to make the sharp left turn off the runway, then when the controller said 'no taxi on Y5,' we had to stop and turn around. As we were doing that he said to just go ahead and use taxiway Y4 now that we were on it. I don't know if he meant to say Y5 the first time and just misspoke, but we know we read back taxiway Y4 and we both heard Y4. I'm not sure who is in the wrong but we called the tower and apologized for any confusion.

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Original NASA ASRS Text

Title: A C525 CREW, AFTER LNDG AT IAD, WERE UNSURE IF THEY WERE CLR OF THE RWY. (PAST THE HOLD LINE) PRIOR TO THE TWR ISSUING TKOF CLRNC TO ANOTHER ACFT.

Narrative: OUR ACFT WAS CLRED FOR A VISUAL LNDG ON RWY 19R AT IAD. ON LNDG THE TWR CTLR SAID EXIT THE RWY ON TXWY Y4 (THAT'S WHAT WE HEARD FIRST AND READ BACK TO HIM). THE CTLR THEN IMMEDIATELY SAID WE WERE GOING THE WRONG WAY AND TO TAXI TO Y5. HE HAD JUST CLRED ANOTHER CITATION FOR TKOF ON RWY 19R AND IN THE CONFUSION OF WHICH TXWY WE WERE SUPPOSED TO BE ON WE MAY HAVE NOT BEEN ACROSS THE ACTIVE RWY MARKINGS. WE WERE NOT ON THE RWY ITSELF, BUT WE ARE NOT SURE IF WE HAD CROSSED THE RWY HOLD SHORT LINE AT THAT POINT. SINCE WE HAD BEEN GIVEN TXWY Y4 FIRST WE HAD TO SLOW DOWN TO MAKE THE SHARP L TURN OFF THE RWY, THEN WHEN THE CTLR SAID 'NO TAXI ON Y5,' WE HAD TO STOP AND TURN AROUND. AS WE WERE DOING THAT HE SAID TO JUST GO AHEAD AND USE TXWY Y4 NOW THAT WE WERE ON IT. I DON'T KNOW IF HE MEANT TO SAY Y5 THE FIRST TIME AND JUST MISSPOKE, BUT WE KNOW WE READ BACK TXWY Y4 AND WE BOTH HEARD Y4. I'M NOT SURE WHO IS IN THE WRONG BUT WE CALLED THE TWR AND APOLOGIZED FOR ANY CONFUSION.

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.