Narrative:

During our usual approach to bos runway 33L, and cleared to land, at about 20 mi till T/D tower cleared an small transport onto the runway for an immediate takeoff. Tower then changed its mind as we approached 200' AGL, cancelled the small transport takeoff clearance and told them to exit the runway. We started a go around as we touched down and the small transport had still not completed cleared the runway at the second taxiway. We then elected to complete the landing as the small transport cleared the second taxiway. The tower controller should never have cleared the small transport onto the runway and we probably should have completed a go around.

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Original NASA ASRS Text

Title: ATCT LCL CTLR HAD 2 ACFT CLEARED ONTO THE RWY--1 FOR TKOF AND 1 TO LAND.

Narrative: DURING OUR USUAL APCH TO BOS RWY 33L, AND CLRED TO LAND, AT ABOUT 20 MI TILL T/D TWR CLRED AN SMT ONTO THE RWY FOR AN IMMEDIATE TKOF. TWR THEN CHANGED ITS MIND AS WE APCHED 200' AGL, CANCELLED THE SMT TKOF CLRNC AND TOLD THEM TO EXIT THE RWY. WE STARTED A GAR AS WE TOUCHED DOWN AND THE SMT HAD STILL NOT COMPLETED CLRED THE RWY AT THE SECOND TXWY. WE THEN ELECTED TO COMPLETE THE LNDG AS THE SMT CLRED THE SECOND TXWY. THE TWR CTLR SHOULD NEVER HAVE CLRED THE SMT ONTO THE RWY AND WE PROBABLY SHOULD HAVE COMPLETED A GAR.

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.