Flight crew of light transport taxied without obtaining tower ground controller clearance.

Attributes
ACN	166703
Time
Date	199012
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : law
State Reference	OK
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	ground : holding ground other : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 3200 flight time type : 700
ASRS Report	166703
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : instrument pilot : atp
Events
Anomaly	non adherence : far other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

After engine start we called lawton ground for taxi and IFR clearance to dfw. After receiving same, or so we thought, we proceeded to taxi. Shortly thereafter, ground control asked for our position on the ramp. We told them we were holding short of runway 17 and ready for departure. This inquiry led us to believe we had taxied west/O clearance. Honestly, I thought we had a clearance to taxi and apparently so did the captain. We could have erred in anticipating the taxi clearance since it was early in the morning and we working a reduced rest schedule due to WX delay the previous day.

Original NASA ASRS Text

Title: FLT CREW OF LTT TAXIED WITHOUT OBTAINING TWR GND CTLR CLRNC.

Narrative: AFTER ENG START WE CALLED LAWTON GND FOR TAXI AND IFR CLRNC TO DFW. AFTER RECEIVING SAME, OR SO WE THOUGHT, WE PROCEEDED TO TAXI. SHORTLY THEREAFTER, GND CTL ASKED FOR OUR POS ON THE RAMP. WE TOLD THEM WE WERE HOLDING SHORT OF RWY 17 AND READY FOR DEP. THIS INQUIRY LED US TO BELIEVE WE HAD TAXIED W/O CLRNC. HONESTLY, I THOUGHT WE HAD A CLRNC TO TAXI AND APPARENTLY SO DID THE CAPT. WE COULD HAVE ERRED IN ANTICIPATING THE TAXI CLRNC SINCE IT WAS EARLY IN THE MORNING AND WE WORKING A REDUCED REST SCHEDULE DUE TO WX DELAY THE PREVIOUS DAY.

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.