FLC OF LTT STARTED TKOF PRIOR TO RECEIVING TKOF CLRNC.

Narrative

IN PROCESS OF DEPARTING MGM FOR BNA. AS ACFT WAS CLOSE TO GROSS WT; AND BECAUSE OF HIGH AMBIENT TEMPS; AUTOMATIC PWR RESERVE WAS REQUIRED FOR TKOF. AUTOMATIC PWR RESERVE USE INVOLVES A TEST OF THAT SYS PLUS THE TORQUE/TEMP LIMITER COMPUTER PRIOR TO FLT. THESE TESTS ARE NORMALLY DONE ON THE RWY JUST BEFORE COMMENCING THE TKOF ROLL. TWR WAS ADVISED THAT WE NEEDED A SHORT PERIOD PRIOR TO TKOF. FLT WAS CLRED 'IN POS AND HOLD; ADVISE WHEN READY.' WE TAXIED INTO POS AND DID THE TESTS. WHEN THE CHKS WERE DONE THE PWR WAS AT 65 PERCENT. AT THAT POINT THE FO ANNOUNCED 'BEFORE TKOF CHK COMPLETE.' WITHOUT A THOUGHT TO OUR CLRNC I ADVANCED THE PWR TO TKOF SETTING AND COMMENCED THE ROLL. WELL INTO THE ROLL THE TWR SAID 'CLRED FOR TKOF.' AT THAT POINT WE REALIZED WE HAD ROLLED WITHOUT A CLRNC. CAUSE OF INCIDENT: INATTN. 2 FACTORS CONTRIBUTED: 1) HABIT PATTERN BROKEN. I DO NOT NORMALLY ADVISE THE TWR OF A NEED TO DELAY IN POS AS THE AUTOMATIC PWR RESERVE AND TTL CHKS TAKE NO MORE THAN 30-40 SECONDS TO COMPLETE. ONCE TKOF CLRNC IS RECEIVED; I RUN THE CHKS AND GO. 2) FATIGUE. BOTH CREW MEMBERS WERE TIRED AND HAD COMMENTED EARLIER ON HOW TIRING THE DAY HAD BEEN. I HAD BEEN AWAKENED AT APPROX 13 HRS PRIOR AND INFORMED OF THE ASSIGNMENT. MY DAY INVOLVED A DEADHEAD FROM RDU TO BNA THEN 3 LEGS; BNA-OWB-BNA-MGM. THROUGHOUT THE PERIOD ACFT CABIN HAD BEEN IN HIGH 80'S TO LOW 90'S DEGS F. COCKPIT IS USUALLY WARMER BUT THERE IS NO GAUGE TO TELL WHAT TEMP IS THERE. FLT CONDITIONS WERE NOT A FACTOR BUT LONG EXPOSURE TO HEAT WAS. IN THIS REGARD; THE COMPANY DOES NOT HAVE SUFFICIENT COOLING EQUIP. SAAB'S AND F17R'S HAVE PRIORITY. AS A RESULT; JETSTREAMS OFTEN ARE DISPATCHED WITH COCKPITS/CABINS ABOVE 85 DEGS F. IN OUR CASE; L BLEED AIR SYS WAS OUT OF COMMISSION. THIS CONTRIBUTED TO LOWER THAN NORMAL COOLING ONCE ENGS WERE STARTED. ON BOARD FREON UNIT IS IN REAR OF ACFT AND DOES LITTLE TO COOL COCKPIT. PROLONGED EXPOSURE TO HIGH TEMPS TAKES ITS TOLL ON CREW ALERTNESS. IT IS ALSO WORTH NOTING THAT WHEN YOU ARE UNCOMFORTABLE -- AND WE WERE -- THAT ONE'S MIND TENDS TO FOCUS ON RELIEVING THE DISCOMFORT. IN THIS CASE; GETTING AIRBORNE ASAP TO LET THE BLEED AIR SYS WORK BETTER.