Narrative:

On the ramp at napa airport, was cleared to taxi to runway 18L. Within a few mins was told to taxi to runway 24 as tower was changing runways. Taxied to runway 24 runup area and checked out aircraft, then advised tower I was 'ready for takeoff runway 24, requesting left downwind departure toward sacramento'. Tower cleared me for takeoff. Started to taxi into position for takeoff when an small aircraft Y came over the runway threshold and landed 150 yards down the runway for a touch and go. Never heard any communication between tower and small aircraft Y. Tower then told me to hold position, then when the small aircraft Y was airborne, tower cleared me for takeoff. Tower and I did not discuss incident (end of story). While technically there does not seem to be fault on the part of the pilot, a more careful survey of approach path before beginning to taxi into position for takeoff would presumably have revealed the approaching small aircraft Y. The submitter is very conscious of this precautionary 'look see' but may have been lulled because runway in use had just been changed and no tower-to-small aircraft Y communications were heard. Therefore, assumed that it was ok to taxi into position for takeoff per clearance from tower.

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Original NASA ASRS Text

Title: CLOSE PROX GA SMA TAXIING INTO POS AND A SECOND SMA XING THE THRESHOLD FOR LNDG.

Narrative: ON THE RAMP AT NAPA ARPT, WAS CLRED TO TAXI TO RWY 18L. WITHIN A FEW MINS WAS TOLD TO TAXI TO RWY 24 AS TWR WAS CHANGING RWYS. TAXIED TO RWY 24 RUNUP AREA AND CHKED OUT ACFT, THEN ADVISED TWR I WAS 'READY FOR TKOF RWY 24, REQUESTING L DOWNWIND DEP TOWARD SACRAMENTO'. TWR CLRED ME FOR TKOF. STARTED TO TAXI INTO POS FOR TKOF WHEN AN SMA Y CAME OVER THE RWY THRESHOLD AND LANDED 150 YARDS DOWN THE RWY FOR A TOUCH AND GO. NEVER HEARD ANY COM BTWN TWR AND SMA Y. TWR THEN TOLD ME TO HOLD POS, THEN WHEN THE SMA Y WAS AIRBORNE, TWR CLRED ME FOR TKOF. TWR AND I DID NOT DISCUSS INCIDENT (END OF STORY). WHILE TECHNICALLY THERE DOES NOT SEEM TO BE FAULT ON THE PART OF THE PLT, A MORE CAREFUL SURVEY OF APCH PATH BEFORE BEGINNING TO TAXI INTO POS FOR TKOF WOULD PRESUMABLY HAVE REVEALED THE APCHING SMA Y. THE SUBMITTER IS VERY CONSCIOUS OF THIS PRECAUTIONARY 'LOOK SEE' BUT MAY HAVE BEEN LULLED BECAUSE RWY IN USE HAD JUST BEEN CHANGED AND NO TWR-TO-SMA Y COMS WERE HEARD. THEREFORE, ASSUMED THAT IT WAS OK TO TAXI INTO POS FOR TKOF PER CLRNC FROM TWR.

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.