C150 PVT PLT STARTED XING ACTIVE RWY DURING TAXI OUT BY MISTAKE DUE TO BELIEVING THAT HE HAD CLRNC TO ANOTHER RWY.

Narrative

AT FLYING CLOUD ARPT; AND WITH GND CTL; ASKED FOR TAXI CLRNC. AT THE TIME THE WIND FAVORED 2 RWYS -- BOTH RWY 18 AND RWYS 27L&R. RWY 18 WAS THE RWY IN USE. GND CTL MADE COMMENTS AS TO CHANGING RWYS TO THE 27 RWYS. WHEN I CALLED FOR TAXI CLRNC; FCM GND SAID 'TAXI TO RWY 18.' ACFT CALLING FOR TAXI CLRNC WERE GIVEN INSTRUCTIONS FOR RWYS 27. I FIGURED I WAS THE LAST ACFT TO USE RWY 18 WHICH MADE SENSE AS I WAS SBOUND AFTER DEP. AS I WAS APCHING RWY 27L TO CROSS IT; I THOUGHT I SHOULD DOUBLECHK MY TAXI CLRNC TO BE SURE IT WAS CORRECT AS THERE WAS A LOT OF TALK OF CHANGING RWYS. I THOUGHT THAT; NO; I DISTINCTLY REMEMBER MY CLRNC AND THE RWY WAS CLR. AS I STARTED TO CROSS RWY 27L; GND COMMANDED ME TO HOLD MY POS (IE; HOLD SHORT OF RWY 27L). I STOPPED IMMEDIATELY AND ASKED 'WAS I GIVEN THAT CLRNC?' TO WHICH GND SAID; 'I ORIGINALLY GAVE YOU TAXI TO RWY 18; BUT I CHANGED IT TO RWY 27L.' I THEN STATED THAT I DID NOT GET THAT INSTRUCTION. I DEPARTED AFTER GETTING EVERYTHING SORTED OUT. I THOUGHT THAT I HAD MISSED A CALL FROM GND OR THAT IT HAD BEEN BLOCKED; BUT A FRIEND WAS MONITORING GND ON HIS RADIO AND HEARD THE WHOLE THING AND WAS WONDERING HOW GND WAS GOING TO CHANGE THE ACTIVE RWY. HE SAID THAT GND GAVE ME ONLY 1 INSTRUCTION; THE ORIGINAL 'TO TAXI TO RWY 18' AND NEVER SAID ANOTHER WORD TO ME. CTLR GAVE A LOT OF INSTRUCTIONS TO OTHER ACFT TO RWY 27. WE ASSUMED THAT GND HAD CONFUSED ME WITH ANOTHER ACFT.