Narrative:

Air carrier X began takeoff roll after both captain and myself heard 'cleared for immediate takeoff'. We noticed that air carrier Y was an medium large transport just beginning to clear the runway. By the time our aircraft was spooled up and indicating 60 KTS. Air carrier Y had cleared runway 36. The controller called us twice but never issued a new clearance or instructions to alert. There was absolutely no conflict. It seems that there should be less emphasis on clearing aircraft for anything and everything as fast as possible. Callback conversation with reporter revealed the following: reporter stated air carrier X had been instructed to 'taxi into position and hold, be prepared for immediately departure'. Air carrier Y had landed and was about 5000' down the runway and about to clear when the captain started takeoff roll. The reporter stated he advised the captain the tower had not cleared them for takeoff. Reporter stated he felt the tower saw they were taking off without a clearance, saw that air carrier Y was clearing downfield and just let it go. Analyst agrees with reporter. Supplemental information from acn 142810: tower cleared air carrier X into position and be ready for immediately takeoff. As we began to spool-up for position movement tower advised cleared for immediate takeoff. Was in process of clearing runway and spooled-up and had in fact cleared the runway prior to us reaching even 60'. Tower called us twice but never said anything to us. A safe takeoff was initiated and completed.

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Original NASA ASRS Text

Title: ACR X UNAUTH TKOF OCCUPIED RWY. ACR X HAD LESS THAN STANDARD SEPARATION FROM ACR Y. PLT DEVIATION.

Narrative: ACR X BEGAN TKOF ROLL AFTER BOTH CAPT AND MYSELF HEARD 'CLRED FOR IMMEDIATE TKOF'. WE NOTICED THAT ACR Y WAS AN MLG JUST BEGINNING TO CLEAR THE RWY. BY THE TIME OUR ACFT WAS SPOOLED UP AND INDICATING 60 KTS. ACR Y HAD CLRED RWY 36. THE CTLR CALLED US TWICE BUT NEVER ISSUED A NEW CLRNC OR INSTRUCTIONS TO ALERT. THERE WAS ABSOLUTELY NO CONFLICT. IT SEEMS THAT THERE SHOULD BE LESS EMPHASIS ON CLEARING ACFT FOR ANYTHING AND EVERYTHING AS FAST AS POSSIBLE. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: REPORTER STATED ACR X HAD BEEN INSTRUCTED TO 'TAXI INTO POSITION AND HOLD, BE PREPARED FOR IMMEDIATELY DEP'. ACR Y HAD LANDED AND WAS ABOUT 5000' DOWN THE RWY AND ABOUT TO CLEAR WHEN THE CAPT STARTED TKOF ROLL. THE REPORTER STATED HE ADVISED THE CAPT THE TWR HAD NOT CLRED THEM FOR TKOF. REPORTER STATED HE FELT THE TWR SAW THEY WERE TAKING OFF WITHOUT A CLRNC, SAW THAT ACR Y WAS CLEARING DOWNFIELD AND JUST LET IT GO. ANALYST AGREES WITH REPORTER. SUPPLEMENTAL INFORMATION FROM ACN 142810: TWR CLRED ACR X INTO POSITION AND BE READY FOR IMMEDIATELY TKOF. AS WE BEGAN TO SPOOL-UP FOR POSITION MOVEMENT TWR ADVISED CLRED FOR IMMEDIATE TKOF. WAS IN PROCESS OF CLEARING RWY AND SPOOLED-UP AND HAD IN FACT CLRED THE RWY PRIOR TO US REACHING EVEN 60'. TWR CALLED US TWICE BUT NEVER SAID ANYTHING TO US. A SAFE TKOF WAS INITIATED AND COMPLETED.

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.