Narrative:

Our aircraft was cleared into position and hold on runway 28 in msy. When we were stopped in position, the captain gave me control of the aircraft, and he took the radios. Tower cleared us for takeoff, and the captain acknowledged the clearance. I advanced the throttles to takeoff power as the captain completed the before takeoff checklist items (exterior lights set, transponder, TCASII set) and called the checklist complete. We heard a garbled radio call and heard tower direct another aircraft on final for runway 1 to go around. I asked the captain to reconfirm our takeoff clearance with tower. He called and asked tower, but I didn't hear him transmit over the radio, just interphone. I called tower and asked to reconfirm takeoff clearance. Tower said continue takeoff (we were about 100 KIAS now), but he had earlier canceled our takeoff clearance since he didn't hear our original acknowledgement. The captain then realized he had been transmitting over interphone, which he had used to talk to the pushback crew. Tower told us that he had no great concern about the incident. The other airplane was apparently vulnerable to our jetblast if he would have landed and rolled to the end. We never heard the takeoff clearance canceled by tower. The captain and I reviewed the events and agreed a good takeoff safety check should include radio switch position.

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Original NASA ASRS Text

Title: B767-332 ACFT CLRED FOR TKOF AND PNF, CAPT, CONFIRMED CLRNC BUT WAS XMITTING ON INTERPHONE SINCE HIS RADIO WAS SET INCORRECTLY. TWR DIDN'T HEAR READBACK AND ISSUED A HOLD CLRNC. REALIZING RPTR ACFT WAS ON TKOF ROLL, TWR HAD ANOTHER ACFT ON APCH GO AROUND.

Narrative: OUR ACFT WAS CLRED INTO POS AND HOLD ON RWY 28 IN MSY. WHEN WE WERE STOPPED IN POS, THE CAPT GAVE ME CTL OF THE ACFT, AND HE TOOK THE RADIOS. TWR CLRED US FOR TKOF, AND THE CAPT ACKNOWLEDGED THE CLRNC. I ADVANCED THE THROTTLES TO TKOF PWR AS THE CAPT COMPLETED THE BEFORE TKOF CHKLIST ITEMS (EXTERIOR LIGHTS SET, XPONDER, TCASII SET) AND CALLED THE CHKLIST COMPLETE. WE HEARD A GARBLED RADIO CALL AND HEARD TWR DIRECT ANOTHER ACFT ON FINAL FOR RWY 1 TO GAR. I ASKED THE CAPT TO RECONFIRM OUR TKOF CLRNC WITH TWR. HE CALLED AND ASKED TWR, BUT I DIDN'T HEAR HIM XMIT OVER THE RADIO, JUST INTERPHONE. I CALLED TWR AND ASKED TO RECONFIRM TKOF CLRNC. TWR SAID CONTINUE TKOF (WE WERE ABOUT 100 KIAS NOW), BUT HE HAD EARLIER CANCELED OUR TKOF CLRNC SINCE HE DIDN'T HEAR OUR ORIGINAL ACKNOWLEDGEMENT. THE CAPT THEN REALIZED HE HAD BEEN XMITTING OVER INTERPHONE, WHICH HE HAD USED TO TALK TO THE PUSHBACK CREW. TWR TOLD US THAT HE HAD NO GREAT CONCERN ABOUT THE INCIDENT. THE OTHER AIRPLANE WAS APPARENTLY VULNERABLE TO OUR JETBLAST IF HE WOULD HAVE LANDED AND ROLLED TO THE END. WE NEVER HEARD THE TKOF CLRNC CANCELED BY TWR. THE CAPT AND I REVIEWED THE EVENTS AND AGREED A GOOD TKOF SAFETY CHK SHOULD INCLUDE RADIO SWITCH POS.

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.