Narrative:

Air carrier X cleared into position to hold on runway 17 by hobby tower. We visually checked the final approach and did not see any traffic. We were on the centerline of the runway just setting the parking brake when small transport Y passed directly over us at an estimated altitude of 30-40 ft, and landed in front of us on runway 17. Cause unknown. Hobby tower is investigating the incident. Supplemental information from acn 190641. Air carrier X on flight from hou-maf was cleared into position and hold runway 17 at houston hobby. As we took the runway we checked final for 17 and saw a medium large transport on final to runway 12R. There was a small twin departing midfield from 17 as we stopped in position. A small transport Y overflew our aircraft by 30-40 ft and landed on runway 17. We heard no clearance issued to anyone to land on 17 prior to taking runway. Tower personnel investigating incident. Supplemental information from acn 191128. While working local at hou which has 4 crossing runways I put a small aircraft in position at runway 17 at foxtrot intersection. I had small transport Y on short final for another runway and I saw an opportunity to reduce his taxi distance so I changed his runway to runway 17 and cleared him to land. Small transport Y landed and turned off at foxtrot and taxied to parking this is when he notified me that there was traffic on the runway. At the time I was very busy and my attention was mostly on events elsewhere around airport. Had I not changed small transport Y landing runway on short final I would have had more time to scan my runway.

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Original NASA ASRS Text

Title: SMT Y WAS CLRED TO LAND ON OCCUPIED RWY OVER THE TOP OF ACR X HOLDING IN POS. LTSS. SYS ERROR. PLTDEV.

Narrative: ACR X CLRED INTO POS TO HOLD ON RWY 17 BY HOBBY TWR. WE VISUALLY CHKED THE FINAL APCH AND DID NOT SEE ANY TFC. WE WERE ON THE CENTERLINE OF THE RWY JUST SETTING THE PARKING BRAKE WHEN SMT Y PASSED DIRECTLY OVER US AT AN ESTIMATED ALT OF 30-40 FT, AND LANDED IN FRONT OF US ON RWY 17. CAUSE UNKNOWN. HOBBY TWR IS INVESTIGATING THE INCIDENT. SUPPLEMENTAL INFO FROM ACN 190641. ACR X ON FLT FROM HOU-MAF WAS CLRED INTO POS AND HOLD RWY 17 AT HOUSTON HOBBY. AS WE TOOK THE RWY WE CHKED FINAL FOR 17 AND SAW A MLG ON FINAL TO RWY 12R. THERE WAS A SMALL TWIN DEPARTING MIDFIELD FROM 17 AS WE STOPPED IN POS. A SMT Y OVERFLEW OUR ACFT BY 30-40 FT AND LANDED ON RWY 17. WE HEARD NO CLRNC ISSUED TO ANYONE TO LAND ON 17 PRIOR TO TAKING RWY. TWR PERSONNEL INVESTIGATING INCIDENT. SUPPLEMENTAL INFO FROM ACN 191128. WHILE WORKING LCL AT HOU WHICH HAS 4 XING RWYS I PUT A SMA IN POS AT RWY 17 AT FOXTROT INTXN. I HAD SMT Y ON SHORT FINAL FOR ANOTHER RWY AND I SAW AN OPPORTUNITY TO REDUCE HIS TAXI DISTANCE SO I CHANGED HIS RWY TO RWY 17 AND CLRED HIM TO LAND. SMT Y LANDED AND TURNED OFF AT FOXTROT AND TAXIED TO PARKING THIS IS WHEN HE NOTIFIED ME THAT THERE WAS TFC ON THE RWY. AT THE TIME I WAS VERY BUSY AND MY ATTN WAS MOSTLY ON EVENTS ELSEWHERE AROUND ARPT. HAD I NOT CHANGED SMT Y LNDG RWY ON SHORT FINAL I WOULD HAVE HAD MORE TIME TO SCAN MY 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.