Narrative:

Approximately XA30 local hours while taxiing out to runway 24, currently in use. Note: there was very little activity at the airport most of the day. Taxiing from FBO west to east. Cleared and crossed runways 17/35. Found the end of the taxiway blocked at the east end. A 180 degree turn was made and at that time faded hatched (yellow) stripes were noted. Taxied back to runways 17/35 intersection, turned right on runway 17/35 (north) and proceeded to runway 24. Reviewing the airport flight guide leads to indicate runways 17/35 as a north taxiway. Expediting taxi to runway 24, turned west and announced on 122.8 taking/departing runway 24 with a downwind departure to the east. Just before lift-off I realized I wasn't on runway 24, but the center taxiway. The takeoff was continued and the area cleared. Factors contributed to the situation: south taxiway poorly marked. High grass between runway and txwys. Flight guide indicated south taxiway through to runway 24. Being unfamiliar with the airport. Suggestions: mark or remark the south taxiway. Weed whack the high grass. Correct the flight guide to show south taxiway not through to runway 24.

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Original NASA ASRS Text

Title: PLT TAXIES OUT FOR TKOF AT RIALTO MUNICIPAL ARPT (CA) AND INADVERTENTLY DEPARTED ON A TXWY. CLAIMS POOR MARKINGS AND TALL GRASS A PROB.

Narrative: APPROX XA30 LCL HRS WHILE TAXIING OUT TO RWY 24, CURRENTLY IN USE. NOTE: THERE WAS VERY LITTLE ACTIVITY AT THE ARPT MOST OF THE DAY. TAXIING FROM FBO W TO E. CLRED AND CROSSED RWYS 17/35. FOUND THE END OF THE TXWY BLOCKED AT THE E END. A 180 DEG TURN WAS MADE AND AT THAT TIME FADED HATCHED (YELLOW) STRIPES WERE NOTED. TAXIED BACK TO RWYS 17/35 INTXN, TURNED R ON RWY 17/35 (N) AND PROCEEDED TO RWY 24. REVIEWING THE ARPT FLT GUIDE LEADS TO INDICATE RWYS 17/35 AS A N TXWY. EXPEDITING TAXI TO RWY 24, TURNED W AND ANNOUNCED ON 122.8 TAKING/DEPARTING RWY 24 WITH A DOWNWIND DEP TO THE E. JUST BEFORE LIFT-OFF I REALIZED I WASN'T ON RWY 24, BUT THE CTR TXWY. THE TKOF WAS CONTINUED AND THE AREA CLRED. FACTORS CONTRIBUTED TO THE SIT: S TXWY POORLY MARKED. HIGH GRASS BTWN RWY AND TXWYS. FLT GUIDE INDICATED S TXWY THROUGH TO RWY 24. BEING UNFAMILIAR WITH THE ARPT. SUGGESTIONS: MARK OR REMARK THE S TXWY. WEED WHACK THE HIGH GRASS. CORRECT THE FLT GUIDE TO SHOW S TXWY NOT THROUGH TO RWY 24.

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.