Narrative:

The lax tower controller clrd widebody transport Y for departure on runway 25L when we were clrd to land and less than a mi to the threshold. At the time of his clearance, widebody transport Y was perpendicular to the runway on the adjoining taxiway. He was not completely in position, power up, and rolling until we passed the half mi to touchdown mark. As we crossed the approach lights at approximately 150' AGL the controller asked if we preferred 25R instead, obviously too late. The first officer responded 'negative'. The first officer then suggested a go around to the captain by stating 'ready for go around'. Captain chose to continue the approach and landed prior to widebody transport Y's rotation point but we were still rocked considerably in the #2 engine's jet wash. A firm landing resulted. This occurrence could have been disastrous and could have been prevented by any one of the following: controller holding on clearing a loaded widebody transport for departure with another aircraft on short final less than 30 seconds to touchdown especially since the aircraft landing was much smaller and lighter than the widebody transport. The crew of the widebody transport seeing the landing aircraft (lights on) on short final and hearing it called short final should have refused the takeoff clearance. Or the captain of the landing small transport aircraft making a go around as the first officer suggested.

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Original NASA ASRS Text

Title: ACR SMT LANDED ON RWY BEFORE WDB ACR BECAME AIRBORNE RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: THE LAX TWR CTLR CLRD WDB Y FOR DEP ON RWY 25L WHEN WE WERE CLRD TO LAND AND LESS THAN A MI TO THE THRESHOLD. AT THE TIME OF HIS CLRNC, WDB Y WAS PERPENDICULAR TO THE RWY ON THE ADJOINING TXWY. HE WAS NOT COMPLETELY IN POSITION, POWER UP, AND ROLLING UNTIL WE PASSED THE HALF MI TO TOUCHDOWN MARK. AS WE CROSSED THE APCH LIGHTS AT APPROX 150' AGL THE CTLR ASKED IF WE PREFERRED 25R INSTEAD, OBVIOUSLY TOO LATE. THE F/O RESPONDED 'NEGATIVE'. THE F/O THEN SUGGESTED A GO AROUND TO THE CAPT BY STATING 'READY FOR GO AROUND'. CAPT CHOSE TO CONTINUE THE APCH AND LANDED PRIOR TO WDB Y'S ROTATION POINT BUT WE WERE STILL ROCKED CONSIDERABLY IN THE #2 ENGINE'S JET WASH. A FIRM LNDG RESULTED. THIS OCCURRENCE COULD HAVE BEEN DISASTROUS AND COULD HAVE BEEN PREVENTED BY ANY ONE OF THE FOLLOWING: CTLR HOLDING ON CLEARING A LOADED WDB FOR DEP WITH ANOTHER ACFT ON SHORT FINAL LESS THAN 30 SECONDS TO TOUCHDOWN ESPECIALLY SINCE THE ACFT LNDG WAS MUCH SMALLER AND LIGHTER THAN THE WDB. THE CREW OF THE WDB SEEING THE LNDG ACFT (LIGHTS ON) ON SHORT FINAL AND HEARING IT CALLED SHORT FINAL SHOULD HAVE REFUSED THE TKOF CLRNC. OR THE CAPT OF THE LNDG SMT ACFT MAKING A GO AROUND AS THE F/O SUGGESTED.

Data retrieved from NASA's ASRS site as of August 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.