Narrative:

Ground control instructed me to taxi to runway 17 via several different txwys, hold short of runway 12L at taxiway echo. Taxi time was approximately 10 mins. After the run-up and switching to tower frequency, I was asked by tower if I was ready for departure and I said yes with a couple pre-takeoff items remaining. I was cleared across 12L and cleared for takeoff with no runway specified. I departed 12R and tower noticed as I was rolling and informed me I was cleared to depart 17, not 12R, there was traffic on short final, so I was cleared for immediate takeoff on 12R. No conflict with other aircraft and no harm done. However, factors I felt contributed to this error was amount of time from clearance to taxi till takeoff, complexity of runway layout, no specific runway takeoff clearance, pilot fatigue and pilot unfamiliarity with airport.

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Original NASA ASRS Text

Title: CHARTER SMT WRONG RWY TKOF AT HOU.

Narrative: GND CTL INSTRUCTED ME TO TAXI TO RWY 17 VIA SEVERAL DIFFERENT TXWYS, HOLD SHORT OF RWY 12L AT TXWY ECHO. TAXI TIME WAS APPROX 10 MINS. AFTER THE RUN-UP AND SWITCHING TO TWR FREQ, I WAS ASKED BY TWR IF I WAS READY FOR DEP AND I SAID YES WITH A COUPLE PRE-TKOF ITEMS REMAINING. I WAS CLRED ACROSS 12L AND CLRED FOR TKOF WITH NO RWY SPECIFIED. I DEPARTED 12R AND TWR NOTICED AS I WAS ROLLING AND INFORMED ME I WAS CLRED TO DEPART 17, NOT 12R, THERE WAS TFC ON SHORT FINAL, SO I WAS CLRED FOR IMMEDIATE TKOF ON 12R. NO CONFLICT WITH OTHER ACFT AND NO HARM DONE. HOWEVER, FACTORS I FELT CONTRIBUTED TO THIS ERROR WAS AMOUNT OF TIME FROM CLRNC TO TAXI TILL TKOF, COMPLEXITY OF RWY LAYOUT, NO SPECIFIC RWY TKOF CLRNC, PLT FATIGUE AND PLT UNFAMILIARITY WITH ARPT.

Data retrieved from NASA's ASRS site as of August 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.