Narrative:

While still on a taxiway some distance from the runway the tower cleared us into position and hold. I thought I heard the first officer read back cleared for takeoff and as we rolled onto the runway started the takeoff roll. The flight engineer questioned the takeoff but both the first officer and I stated we were cleared for takeoff. The flight engineer did not question it further thinking he may have missed something while doing a checklist. After takeoff the tower questioned us about our heading, told us to turn left to 220 degree, had us to stay with the tower then to call departure. Departure did ask about a takeoff clearance we answered that we understood we had been cleared. Backgnd: had flown 16 hours in 4 days, a short overnight in ord (10 hours), a change of airplanes at departure time which caused us to be 45 mins late out of the gate. This on top of over a yr of not knowing if the company was going to be in business the next week or month due to its owner and his handling. The stress on all crews has been very high and no doubt affects us all in our operation. Supplemental information from acn 188269: I believe some of the contributing factors could be receiving takeoff clearance too early, short night (arrived at hotel approximately PM45 and departed hotel AM00) time is 2 hours off west coast time where I live. This was third day of trip. Supplemental information from acn 188509: as we were taking the runway, the captain (PF) started applying takeoff power. I (flight engineer) said, 'did he clear us'? The captain responded 'yes' and continued takeoff. Then departure control said, 'air carrier X, between you and me, were you cleared for takeoff'? We said, 'we understood we were, but we could be mistaken'. Departure control said, 'ok, just between you and me, no problem', air carrier X contact chicago center (frequency) we'll see ya later'. There was never any conflict with any other aircraft. Traffic was very light that early morning. I still don't think we were cleared for takeoff, but in any case I think the problem occurred because we were cleared into position long before we even got to the end of the runway. A good 45 seconds went by, by the time we were rolling. By that time I don't think it was clear in any of our minds what we were really cleared for.

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Original NASA ASRS Text

Title: UNAUTHORIZED TKOF, CLRNC DISPUTED BY TWR, DEP CTLR.

Narrative: WHILE STILL ON A TAXIWAY SOME DISTANCE FROM THE RWY THE TWR CLRED US INTO POS AND HOLD. I THOUGHT I HEARD THE FO READ BACK CLRED FOR TKOF AND AS WE ROLLED ONTO THE RWY STARTED THE TKOF ROLL. THE FE QUESTIONED THE TKOF BUT BOTH THE FO AND I STATED WE WERE CLRED FOR TKOF. THE FE DID NOT QUESTION IT FURTHER THINKING HE MAY HAVE MISSED SOMETHING WHILE DOING A CHKLIST. AFTER TKOF THE TWR QUESTIONED US ABOUT OUR HDG, TOLD US TO TURN L TO 220 DEG, HAD US TO STAY WITH THE TWR THEN TO CALL DEP. DEP DID ASK ABOUT A TKOF CLRNC WE ANSWERED THAT WE UNDERSTOOD WE HAD BEEN CLRED. BACKGND: HAD FLOWN 16 HRS IN 4 DAYS, A SHORT OVERNIGHT IN ORD (10 HRS), A CHANGE OF AIRPLANES AT DEP TIME WHICH CAUSED US TO BE 45 MINS LATE OUT OF THE GATE. THIS ON TOP OF OVER A YR OF NOT KNOWING IF THE COMPANY WAS GOING TO BE IN BUSINESS THE NEXT WK OR MONTH DUE TO ITS OWNER AND HIS HANDLING. THE STRESS ON ALL CREWS HAS BEEN VERY HIGH AND NO DOUBT AFFECTS US ALL IN OUR OP. SUPPLEMENTAL INFO FROM ACN 188269: I BELIEVE SOME OF THE CONTRIBUTING FACTORS COULD BE RECEIVING TKOF CLRNC TOO EARLY, SHORT NIGHT (ARRIVED AT HOTEL APPROX PM45 AND DEPARTED HOTEL AM00) TIME IS 2 HRS OFF W COAST TIME WHERE I LIVE. THIS WAS THIRD DAY OF TRIP. SUPPLEMENTAL INFO FROM ACN 188509: AS WE WERE TAKING THE RWY, THE CAPT (PF) STARTED APPLYING TKOF PWR. I (FE) SAID, 'DID HE CLR US'? THE CAPT RESPONDED 'YES' AND CONTINUED TKOF. THEN DEP CTL SAID, 'ACR X, BTWN YOU AND ME, WERE YOU CLRED FOR TKOF'? WE SAID, 'WE UNDERSTOOD WE WERE, BUT WE COULD BE MISTAKEN'. DEP CTL SAID, 'OK, JUST BTWN YOU AND ME, NO PROBLEM', ACR X CONTACT CHICAGO CENTER (FREQ) WE'LL SEE YA LATER'. THERE WAS NEVER ANY CONFLICT WITH ANY OTHER ACFT. TFC WAS VERY LIGHT THAT EARLY MORNING. I STILL DON'T THINK WE WERE CLRED FOR TKOF, BUT IN ANY CASE I THINK THE PROBLEM OCCURRED BECAUSE WE WERE CLRED INTO POS LONG BEFORE WE EVEN GOT TO THE END OF THE RWY. A GOOD 45 SECONDS WENT BY, BY THE TIME WE WERE ROLLING. BY THAT TIME I DON'T THINK IT WAS CLR IN ANY OF OUR MINDS WHAT WE WERE REALLY CLRED FOR.

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.