A C172 CFI departed on the wrong runway at GGG.

Attributes
ACN	627792
Time
Date	200408
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ggg.airport
State Reference	TX
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : ggg.tower
Operator	general aviation : instructional
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	ground : takeoff roll
Flight Plan	IFR
Person 1
Affiliation	other
Function	instruction : instructor
Qualification	pilot : instrument pilot : commercial pilot : cfi
Experience	flight time last 90 days : 20 flight time total : 405 flight time type : 400
ASRS Report	627792
Person 2
Affiliation	government : faa
Function	controller : local
Events
Anomaly	incursion : runway non adherence : far non adherence : clearance
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was holding short of runway 17/35, runway 13/31 at intersection H. I was cleared to take off on runway 17. I taxied onto the runway and started rolling on runway 13, thinking I was on runway 17. I realized my mistake when I checked my compass. There was no other traffic on the airport at the time. It was a stupid mistake that could easily have been prevented had I checked the compass/directional gyro to confirm I was actually pointing down runway 17 and not runway 13. This event took place at GGG.

Original NASA ASRS Text

Title: A C172 CFI DEPARTED ON THE WRONG RWY AT GGG.

Narrative: I WAS HOLDING SHORT OF RWY 17/35, RWY 13/31 AT INTXN H. I WAS CLRED TO TAKE OFF ON RWY 17. I TAXIED ONTO THE RWY AND STARTED ROLLING ON RWY 13, THINKING I WAS ON RWY 17. I REALIZED MY MISTAKE WHEN I CHKED MY COMPASS. THERE WAS NO OTHER TFC ON THE ARPT AT THE TIME. IT WAS A STUPID MISTAKE THAT COULD EASILY HAVE BEEN PREVENTED HAD I CHKED THE COMPASS/DIRECTIONAL GYRO TO CONFIRM I WAS ACTUALLY POINTING DOWN RWY 17 AND NOT RWY 13. THIS EVENT TOOK PLACE AT GGG.

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.