Narrative:

Small aircraft X was flying from pao to hwd. Contacted hwd over coyote hills, was instructed heading 360 degrees to intercept runway 28R centerline. Small aircraft X was cleared to land and acknowledged clearance and runway 28R. When I was about 3/4 mi out, a red/white small aircraft Y taxied onto runway 28R and 4-6 seconds later, began a takeoff roll. I sidestepped right, executed a balked landing, and contacted tower. Tower apologized, but did not issue instructions to either aircraft. I entered right traffic, contacted runway and requested instructions and was cleared to land. After landing, I asked tower if the small aircraft Y had been cleared for takeoff. Tower said it had been, but had been slow to depart. This was inconsistent with my observation that small aircraft Y began its takeoff roll within 4-6 seconds of taxiing onto the runway.

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Original NASA ASRS Text

Title: SMA X EXECUTED GAR FROM OCCUPIED RWY, HAD NMAC WITH SMA Y TAKING OFF. SEE AND AVOID CONCEPT.

Narrative: SMA X WAS FLYING FROM PAO TO HWD. CONTACTED HWD OVER COYOTE HILLS, WAS INSTRUCTED HDG 360 DEGS TO INTERCEPT RWY 28R CTRLINE. SMA X WAS CLRED TO LAND AND ACKNOWLEDGED CLRNC AND RWY 28R. WHEN I WAS ABOUT 3/4 MI OUT, A RED/WHITE SMA Y TAXIED ONTO RWY 28R AND 4-6 SECONDS LATER, BEGAN A TKOF ROLL. I SIDESTEPPED R, EXECUTED A BALKED LNDG, AND CONTACTED TWR. TWR APOLOGIZED, BUT DID NOT ISSUE INSTRUCTIONS TO EITHER ACFT. I ENTERED R TFC, CONTACTED RWY AND REQUESTED INSTRUCTIONS AND WAS CLRED TO LAND. AFTER LNDG, I ASKED TWR IF THE SMA Y HAD BEEN CLRED FOR TKOF. TWR SAID IT HAD BEEN, BUT HAD BEEN SLOW TO DEPART. THIS WAS INCONSISTENT WITH MY OBSERVATION THAT SMA Y BEGAN ITS TKOF ROLL WITHIN 4-6 SECONDS OF TAXIING ONTO THE 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.