Narrative:

Air carrier X called ready for departure runway 16L. I instructed the aircraft to taxi into position and hold anticipating takeoff clearance after a military aircraft departing runway 16R. Both aircraft were departing IFR to sacramento departures east radar sector. After 'running' the sequence down to east radar, I inadvertently filed air carrier X departure strip. I subsequently cleared atx Y, 8 mi north, to land on runway 16L. I was distracted by a MTR in the VFR pattern for runway 16R. The MTR was unable to maintain VFR conditions due to a low stratus layer and was requesting instrument approachs. I coordinated climb out and release with west radar for MTR. Since atx Y was sequenced to the left runway because of MTR on the right I attempted to change landing runways to runway 16R because I know that atx Y pilots prefer runway 16R. Atx Y said he was lined up on the left 3 mi final and would go ahead and land on the left. Upon scanning the runway I did not notice air carrier X in takeoff position. In retrospect, air carrier X's lights seemed to blend in with the runway and approach lights and the ground control's BRITE radar display partially blocked my view of the approach end of runway 16L. When I checked to see if atx Y had landed and cleared the runway I saw air carrier X in takeoff position. Air carrier X called at that time and wanted to know what was going on. After I apologized and gave air carrier X our telephone numbers, atx Y told air carrier X to relax, he had their aircraft in sight, was cleared to land and landed. They were in no danger. I believe the factors which contributed to this occurrence were my inadvertently filing the departure strip, the distraction by MTR due to MVFR WX conditions, my partially blocked view of the approach and had I moved 1 step to the right my view would have been unobstructed and atx Y pilot electing to land on an occupied runway.

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Original NASA ASRS Text

Title: ATX Y LANDED ON OCCUPIED RWY HAD LTSS FROM ACR X. SYS ERROR PLTDEV.

Narrative: ACR X CALLED READY FOR DEP RWY 16L. I INSTRUCTED THE ACFT TO TAXI INTO POS AND HOLD ANTICIPATING TKOF CLRNC AFTER A MIL ACFT DEPARTING RWY 16R. BOTH ACFT WERE DEPARTING IFR TO SACRAMENTO DEPS E RADAR SECTOR. AFTER 'RUNNING' THE SEQUENCE DOWN TO E RADAR, I INADVERTENTLY FILED ACR X DEP STRIP. I SUBSEQUENTLY CLRED ATX Y, 8 MI N, TO LAND ON RWY 16L. I WAS DISTRACTED BY A MTR IN THE VFR PATTERN FOR RWY 16R. THE MTR WAS UNABLE TO MAINTAIN VFR CONDITIONS DUE TO A LOW STRATUS LAYER AND WAS REQUESTING INST APCHS. I COORDINATED CLBOUT AND RELEASE WITH W RADAR FOR MTR. SINCE ATX Y WAS SEQUENCED TO THE L RWY BECAUSE OF MTR ON THE R I ATTEMPTED TO CHANGE LNDG RWYS TO RWY 16R BECAUSE I KNOW THAT ATX Y PLTS PREFER RWY 16R. ATX Y SAID HE WAS LINED UP ON THE L 3 MI FINAL AND WOULD GO AHEAD AND LAND ON THE L. UPON SCANNING THE RWY I DID NOT NOTICE ACR X IN TKOF POS. IN RETROSPECT, ACR X'S LIGHTS SEEMED TO BLEND IN WITH THE RWY AND APCH LIGHTS AND THE GND CTL'S BRITE RADAR DISPLAY PARTIALLY BLOCKED MY VIEW OF THE APCH END OF RWY 16L. WHEN I CHKED TO SEE IF ATX Y HAD LANDED AND CLRED THE RWY I SAW ACR X IN TKOF POS. ACR X CALLED AT THAT TIME AND WANTED TO KNOW WHAT WAS GOING ON. AFTER I APOLOGIZED AND GAVE ACR X OUR TELEPHONE NUMBERS, ATX Y TOLD ACR X TO RELAX, HE HAD THEIR ACFT IN SIGHT, WAS CLRED TO LAND AND LANDED. THEY WERE IN NO DANGER. I BELIEVE THE FACTORS WHICH CONTRIBUTED TO THIS OCCURRENCE WERE MY INADVERTENTLY FILING THE DEP STRIP, THE DISTR BY MTR DUE TO MVFR WX CONDITIONS, MY PARTIALLY BLOCKED VIEW OF THE APCH AND HAD I MOVED 1 STEP TO THE R MY VIEW WOULD HAVE BEEN UNOBSTRUCTED AND ATX Y PLT ELECTING TO LAND ON AN OCCUPIED RWY.

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.