Narrative:

Called ground for taxi. The clearance included a back-taxi on a runway. The runways are runway 21L and runway 21R. Back taxiing on runway 21R is normal, but I thought ground said to back-taxi on runway 21L. This made sense, because I was right next to runway 21L. I repeated back clearance, including the runway 21L runway back-taxi. After crossing the runway boundary yellow line, ground called and said I was going the wrong way. They then cleared me to back-taxi on runway 21L. Even though I repeated back the clearance to include the back-taxi, maybe I should have queried ground control, since the clearance was different than usual. I have heard of controllers not listening to readbacks as they are thinking ahead to their next thing.

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Original NASA ASRS Text

Title: C152 PLT HAD A RWY INCURSION AT LUK.

Narrative: CALLED GND FOR TAXI. THE CLRNC INCLUDED A BACK-TAXI ON A RWY. THE RWYS ARE RWY 21L AND RWY 21R. BACK TAXIING ON RWY 21R IS NORMAL, BUT I THOUGHT GND SAID TO BACK-TAXI ON RWY 21L. THIS MADE SENSE, BECAUSE I WAS RIGHT NEXT TO RWY 21L. I REPEATED BACK CLRNC, INCLUDING THE RWY 21L RWY BACK-TAXI. AFTER XING THE RWY BOUNDARY YELLOW LINE, GND CALLED AND SAID I WAS GOING THE WRONG WAY. THEY THEN CLRED ME TO BACK-TAXI ON RWY 21L. EVEN THOUGH I REPEATED BACK THE CLRNC TO INCLUDE THE BACK-TAXI, MAYBE I SHOULD HAVE QUERIED GND CTL, SINCE THE CLRNC WAS DIFFERENT THAN USUAL. I HAVE HEARD OF CTLRS NOT LISTENING TO READBACKS AS THEY ARE THINKING AHEAD TO THEIR NEXT THING.

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.