Narrative:

Approaching intersection of txwys a and C I brought the aircraft to a stop. Our clearance was hold short of runway 27 at taxiway C. Ground control was confused as to where we were and asked us if we were the aircraft on taxiway north. The first officer replied, no, air carrier X is on taxiway a. A DC10, was trying to clear runway 27 at the end and there was a B727 approaching the intersection of txwys a and north (a conflict). Ground control's xmissions appeared to be somewhat broken or incomplete. While receiving our company's ramp parking confirmation from the ramp tower, ground control called - the first officer (all of us agreed) believed we were 'cleared across runway 27 on taxiway C.' he read back the clearance as 'air carrier X cleared to cross runway 27 on taxiway C.' the DC10 was still clearing the runway to our left and the closest aircraft visible on final was 5-6 mi out. I turned on the taxi light, released brakes, turned left onto taxiway C, visually cleared both directions again then crossed runway 27 at taxiway C. North of runway 27 as we were turning east on taxiway V, ground control asked 'air carrier X, is that you north of runway 27?' the first officer answered 'air carrier X affirmative. You cleared us across.' the ground controller stated 'no, I did not.' the remaining taxi to parking was uneventful. I talked to the tower supervisor later (about 30 mins later). He said we were not cleared to cross but confirmed our readback, ground controller's failure to catch it and bad radio reception as well as 'confusion.' no further action.

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Original NASA ASRS Text

Title: RWY INCURSION AT MEM, TN, WHEN XING CLRNC READBACK IS NOT QUESTIONED BY TWR WHO PURPORTS THAT IT WAS NOT GIVEN.

Narrative: APCHING INTXN OF TXWYS A AND C I BROUGHT THE ACFT TO A STOP. OUR CLRNC WAS HOLD SHORT OF RWY 27 AT TXWY C. GND CTL WAS CONFUSED AS TO WHERE WE WERE AND ASKED US IF WE WERE THE ACFT ON TXWY N. THE FO REPLIED, NO, ACR X IS ON TXWY A. A DC10, WAS TRYING TO CLR RWY 27 AT THE END AND THERE WAS A B727 APCHING THE INTXN OF TXWYS A AND N (A CONFLICT). GND CTL'S XMISSIONS APPEARED TO BE SOMEWHAT BROKEN OR INCOMPLETE. WHILE RECEIVING OUR COMPANY'S RAMP PARKING CONFIRMATION FROM THE RAMP TWR, GND CTL CALLED - THE FO (ALL OF US AGREED) BELIEVED WE WERE 'CLRED ACROSS RWY 27 ON TXWY C.' HE READ BACK THE CLRNC AS 'ACR X CLRED TO CROSS RWY 27 ON TXWY C.' THE DC10 WAS STILL CLRING THE RWY TO OUR L AND THE CLOSEST ACFT VISIBLE ON FINAL WAS 5-6 MI OUT. I TURNED ON THE TAXI LIGHT, RELEASED BRAKES, TURNED L ONTO TXWY C, VISUALLY CLRED BOTH DIRECTIONS AGAIN THEN CROSSED RWY 27 AT TXWY C. N OF RWY 27 AS WE WERE TURNING E ON TXWY V, GND CTL ASKED 'ACR X, IS THAT YOU N OF RWY 27?' THE FO ANSWERED 'ACR X AFFIRMATIVE. YOU CLRED US ACROSS.' THE GND CTLR STATED 'NO, I DID NOT.' THE REMAINING TAXI TO PARKING WAS UNEVENTFUL. I TALKED TO THE TWR SUPVR LATER (ABOUT 30 MINS LATER). HE SAID WE WERE NOT CLRED TO CROSS BUT CONFIRMED OUR READBACK, GND CTLR'S FAILURE TO CATCH IT AND BAD RADIO RECEPTION AS WELL AS 'CONFUSION.' NO FURTHER ACTION.

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.