Narrative:

While holding short of runway 7L at taxiway F11, phx tower instructed us to cross runway 7L and turn right on taxiway east. My copilot read back the clearance, and I began to cross runway 7L. There was a B757 on the departure end of runway 7L, which appeared to be stationary. Approximately 10 ft past the runway hold-short markings, and prior to actually crossing the white line marking the runway, tower instructed 'stop.' I stopped immediately (maximum braking), and simultaneously noted that the B757 was rolling at the departure end of runway 7L. The tower then advised the B757 to stop the takeoff. The B757 aborted his takeoff, which appeared to be in the slow speed regime (just starting his takeoff roll), and he taxied off the runway well clear of our position somewhere between taxiway E6 and taxiway E8. Tower then instructed us again to cross runway 7L at taxiway F11 and turn right on taxiway east. He furthermore apologized for his earlier clearance. We taxied to the terminal without further incident. I called the tower on the phone line upon reaching the gate. The tower supervisor confirmed that they had, in fact, issued a valid runway 7L crossing instruction to my aircraft after they had cleared the B757 for takeoff. He further clarified that this was primarily their error.

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Original NASA ASRS Text

Title: PHX LCL CTLR INSTRUCTS A CRJ700 CREW TO CROSS RWY 7L, THEN CLRS A B757 FOR TKOF ON THE SAME RWY.

Narrative: WHILE HOLDING SHORT OF RWY 7L AT TXWY F11, PHX TWR INSTRUCTED US TO CROSS RWY 7L AND TURN R ON TXWY E. MY COPLT READ BACK THE CLRNC, AND I BEGAN TO CROSS RWY 7L. THERE WAS A B757 ON THE DEP END OF RWY 7L, WHICH APPEARED TO BE STATIONARY. APPROX 10 FT PAST THE RWY HOLD-SHORT MARKINGS, AND PRIOR TO ACTUALLY XING THE WHITE LINE MARKING THE RWY, TWR INSTRUCTED 'STOP.' I STOPPED IMMEDIATELY (MAX BRAKING), AND SIMULTANEOUSLY NOTED THAT THE B757 WAS ROLLING AT THE DEP END OF RWY 7L. THE TWR THEN ADVISED THE B757 TO STOP THE TKOF. THE B757 ABORTED HIS TKOF, WHICH APPEARED TO BE IN THE SLOW SPD REGIME (JUST STARTING HIS TKOF ROLL), AND HE TAXIED OFF THE RWY WELL CLR OF OUR POS SOMEWHERE BTWN TXWY E6 AND TXWY E8. TWR THEN INSTRUCTED US AGAIN TO CROSS RWY 7L AT TXWY F11 AND TURN R ON TXWY E. HE FURTHERMORE APOLOGIZED FOR HIS EARLIER CLRNC. WE TAXIED TO THE TERMINAL WITHOUT FURTHER INCIDENT. I CALLED THE TWR ON THE PHONE LINE UPON REACHING THE GATE. THE TWR SUPVR CONFIRMED THAT THEY HAD, IN FACT, ISSUED A VALID RWY 7L XING INSTRUCTION TO MY ACFT AFTER THEY HAD CLRED THE B757 FOR TKOF. HE FURTHER CLARIFIED THAT THIS WAS PRIMARILY THEIR ERROR.

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.