GA small aircraft takeoff on taxiway at 90 degree angle to assigned runway.

Attributes
ACN	90666
Time
Date	198807
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : dbq
State Reference	IA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	climbout : takeoff
Flight Plan	VFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 25 flight time total : 275 flight time type : 165
ASRS Report	90666
Person 2
Affiliation	government : faa
Function	controller : ground
Qualification	controller : non radar
Events
Anomaly	aircraft equipment problem : less severe non adherence : clearance non adherence : published procedure other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Landed at dbq for refueling on flight from 3HO. Took on fuel and went to FSS for WX update. Called ground control on 121.8 and advised them I request a progressive taxi to the active runway. Runway 31 in use at time. A left turn was made from FBO ramp via southeast taxiway to first right turn taxiway. Stopped on hold mark runway 31. Advised by ground control we had approximately 4000' of runway clear for takeoff. Windsock was to our right--showed wind from approximately 280 degrees at 8 KTS. Wet compass showed 310 degrees. Dg was set preflight and run up was done. Ground control stated, 'clear for takeoff, you have 4000' of usable runway in front of you.' wet compass showed 310 degrees along with dg setting at 310 degrees. Power was added and lift off speed was attained when I noticed we were on a taxiway. Too late to abort. Up on lift off tower stated we took off from a taxiway. I stated we were not aware of this until ground roll speed was too high to abort and my wet compass must be inaccurate. Upon checking the compass dash mount, we found it to be 60-80 degrees out on northwest and southwest headings. Compass will be replaced with new one. Also, ground control should have taxied us to the end of runway 31. No error could have been made then, and compass and dg would have not matched heading.

Original NASA ASRS Text

Title: GA SMA TKOF ON TXWY AT 90 DEGREE ANGLE TO ASSIGNED RWY.

Narrative: LANDED AT DBQ FOR REFUELING ON FLT FROM 3HO. TOOK ON FUEL AND WENT TO FSS FOR WX UPDATE. CALLED GND CTL ON 121.8 AND ADVISED THEM I REQUEST A PROGRESSIVE TAXI TO THE ACTIVE RWY. RWY 31 IN USE AT TIME. A LEFT TURN WAS MADE FROM FBO RAMP VIA SE TXWY TO FIRST RIGHT TURN TXWY. STOPPED ON HOLD MARK RWY 31. ADVISED BY GND CTL WE HAD APPROX 4000' OF RWY CLR FOR TKOF. WINDSOCK WAS TO OUR RIGHT--SHOWED WIND FROM APPROX 280 DEGS AT 8 KTS. WET COMPASS SHOWED 310 DEGS. DG WAS SET PREFLT AND RUN UP WAS DONE. GND CTL STATED, 'CLR FOR TKOF, YOU HAVE 4000' OF USABLE RWY IN FRONT OF YOU.' WET COMPASS SHOWED 310 DEGS ALONG WITH DG SETTING AT 310 DEGS. PWR WAS ADDED AND LIFT OFF SPD WAS ATTAINED WHEN I NOTICED WE WERE ON A TXWY. TOO LATE TO ABORT. UP ON LIFT OFF TWR STATED WE TOOK OFF FROM A TXWY. I STATED WE WERE NOT AWARE OF THIS UNTIL GND ROLL SPD WAS TOO HIGH TO ABORT AND MY WET COMPASS MUST BE INACCURATE. UPON CHKING THE COMPASS DASH MOUNT, WE FOUND IT TO BE 60-80 DEGS OUT ON NW AND SW HDGS. COMPASS WILL BE REPLACED WITH NEW ONE. ALSO, GND CTL SHOULD HAVE TAXIED US TO THE END OF RWY 31. NO ERROR COULD HAVE BEEN MADE THEN, AND COMPASS AND DG WOULD HAVE NOT MATCHED HDG.

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.