Narrative:

Taxiing for takeoff runway 9L at fll. Switched to tower frequency after crossing runway 13/31. Taxi checklist had already been completed. With approximately 1500 ft to taxi to departure end of runway 9L, fll tower cleared us for takeoff before we requested takeoff clearance. We acknowledged the clearance and completed takeoff checklist. We then saw a single engine cessna taxi rapidly across the warm-up area onto runway 9L and begin takeoff roll. We thought that was somewhat unusual, but assumed the cessna had received takeoff clearance before we switched to tower frequency. Nonetheless, we asked tower to reconfirm our takeoff clearance. Tower confirmed our clearance as we reached the end of the runway. We turned onto runway 9L and control was xferred to first officer who began takeoff. After EPR had been selected to engage autothrottles, PNF (captain) noticed that the cessna was airborne but still on runway centerline. PNF transmitted to tower, 'is the cessna going to turn?' after a short pause, the tower's answer was, 'what cessna?' it immediately became apparent that the cessna had departed without clearance. As we were now into our takeoff roll, it seemed clear that a high speed abort was not advised. PNF responded to tower, 'the cessna that just took off runway 9L, we have him visually and will turn left immediately when airborne.' the tower then idented the cessna and instructed it to make an immediate 20 degree right turn. It complied and lateral separation was instantly established. The cessna was continually kept in visual contact by both pilots and collision was never imminent. Tower gave us a new heading to fly and switched us to departure control. They also said they would deal with the cessna pilot.

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Original NASA ASRS Text

Title: FLC OF A B757-200 NOTICED A SEL CESSNA TAXI ONTO THEIR RWY AND TAKE OFF WHEN THEY ALREADY HAD RECEIVED TKOF CLRNC. AS THEY ROLLED FOR TKOF, THE CESSNA WAS OBSERVED CLBING OUT ON RWY HDG. WHEN RPTR ASKED IF THE CESSNA WAS GOING TO TURN OUT, THE TWR ADVISED THAT THEY DID NOT KNOW ABOUT ANY CESSNA.

Narrative: TAXIING FOR TKOF RWY 9L AT FLL. SWITCHED TO TWR FREQ AFTER XING RWY 13/31. TAXI CHKLIST HAD ALREADY BEEN COMPLETED. WITH APPROX 1500 FT TO TAXI TO DEP END OF RWY 9L, FLL TWR CLRED US FOR TKOF BEFORE WE REQUESTED TKOF CLRNC. WE ACKNOWLEDGED THE CLRNC AND COMPLETED TKOF CHKLIST. WE THEN SAW A SINGLE ENG CESSNA TAXI RAPIDLY ACROSS THE WARM-UP AREA ONTO RWY 9L AND BEGIN TKOF ROLL. WE THOUGHT THAT WAS SOMEWHAT UNUSUAL, BUT ASSUMED THE CESSNA HAD RECEIVED TKOF CLRNC BEFORE WE SWITCHED TO TWR FREQ. NONETHELESS, WE ASKED TWR TO RECONFIRM OUR TKOF CLRNC. TWR CONFIRMED OUR CLRNC AS WE REACHED THE END OF THE RWY. WE TURNED ONTO RWY 9L AND CTL WAS XFERRED TO FO WHO BEGAN TKOF. AFTER EPR HAD BEEN SELECTED TO ENGAGE AUTOTHROTTLES, PNF (CAPT) NOTICED THAT THE CESSNA WAS AIRBORNE BUT STILL ON RWY CTRLINE. PNF XMITTED TO TWR, 'IS THE CESSNA GOING TO TURN?' AFTER A SHORT PAUSE, THE TWR'S ANSWER WAS, 'WHAT CESSNA?' IT IMMEDIATELY BECAME APPARENT THAT THE CESSNA HAD DEPARTED WITHOUT CLRNC. AS WE WERE NOW INTO OUR TKOF ROLL, IT SEEMED CLR THAT A HIGH SPD ABORT WAS NOT ADVISED. PNF RESPONDED TO TWR, 'THE CESSNA THAT JUST TOOK OFF RWY 9L, WE HAVE HIM VISUALLY AND WILL TURN L IMMEDIATELY WHEN AIRBORNE.' THE TWR THEN IDENTED THE CESSNA AND INSTRUCTED IT TO MAKE AN IMMEDIATE 20 DEG R TURN. IT COMPLIED AND LATERAL SEPARATION WAS INSTANTLY ESTABLISHED. THE CESSNA WAS CONTINUALLY KEPT IN VISUAL CONTACT BY BOTH PLTS AND COLLISION WAS NEVER IMMINENT. TWR GAVE US A NEW HDG TO FLY AND SWITCHED US TO DEP CTL. THEY ALSO SAID THEY WOULD DEAL WITH THE CESSNA PLT.

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.