Narrative:

I was the lead plane in a flight of 4 aircraft. We were separated on the ramp apron, partly due to a jet departing from the same apron. I called ground and asked to taxi the flight to runway 27L. I thought I heard and read back 'cleared to taxi runway 27L via taxiway C.' thinking I was cleared all the way across both active runways 27R&left, I taxied onto taxiway C and turned at taxiway B and instinctively held short of runway 27R and looked at the rest of my flight. The airplane assigned #3 had taxied onto taxiway C and stopped awaiting #2, which was still in its original position. I waited a while, thinking #2 had a problem. Meanwhile, the jet received its IFR release and was moving onto, or toward, the runway. I, still thinking I was cleared across runway 27R, and in the way of the soon departing jet, checked for landing traffic and crossed runway 27R.

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Original NASA ASRS Text

Title: A VERY LOW TIME C172 PLT, TRYING TO LEAD A FLT OF 4, CROSSED RWY 27R AT SEE, WITHOUT PERMISSION.

Narrative: I WAS THE LEAD PLANE IN A FLT OF 4 ACFT. WE WERE SEPARATED ON THE RAMP APRON, PARTLY DUE TO A JET DEPARTING FROM THE SAME APRON. I CALLED GND AND ASKED TO TAXI THE FLT TO RWY 27L. I THOUGHT I HEARD AND READ BACK 'CLRED TO TAXI RWY 27L VIA TXWY C.' THINKING I WAS CLRED ALL THE WAY ACROSS BOTH ACTIVE RWYS 27R&L, I TAXIED ONTO TXWY C AND TURNED AT TXWY B AND INSTINCTIVELY HELD SHORT OF RWY 27R AND LOOKED AT THE REST OF MY FLT. THE AIRPLANE ASSIGNED #3 HAD TAXIED ONTO TXWY C AND STOPPED AWAITING #2, WHICH WAS STILL IN ITS ORIGINAL POS. I WAITED A WHILE, THINKING #2 HAD A PROB. MEANWHILE, THE JET RECEIVED ITS IFR RELEASE AND WAS MOVING ONTO, OR TOWARD, THE RWY. I, STILL THINKING I WAS CLRED ACROSS RWY 27R, AND IN THE WAY OF THE SOON DEPARTING JET, CHKED FOR LNDG TFC AND CROSSED RWY 27R.

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.