Narrative:

Oakland ground control cleared C177 to runway 27L via taxiway C, taxiway B to the run-up area. A passenger was asking questions about IFR WX at mry when I thought I heard a tower clearance, 'in position and hold.' I rogered the transmission and taxied into position to hold on runway 27L. Tower immediately asked me to exit runway 27L. The clearance was to 'hold at the hold line, not to taxi in position and hold.' I apologized. I now repeat all clrncs rather than offering a simple 'roger that.' safety in this case was not compromised since no aircraft was on final approach. But if there had been, I might have caused an incident.

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Original NASA ASRS Text

Title: C177 PLT TAXIES PAST THE HOLD LINE INTO POS AND HOLD WHEN THE CTLR INSTRUCTED HIM TO HOLD AT THE HOLD LINE.

Narrative: OAKLAND GND CTL CLRED C177 TO RWY 27L VIA TXWY C, TXWY B TO THE RUN-UP AREA. A PAX WAS ASKING QUESTIONS ABOUT IFR WX AT MRY WHEN I THOUGHT I HEARD A TWR CLRNC, 'IN POS AND HOLD.' I ROGERED THE XMISSION AND TAXIED INTO POS TO HOLD ON RWY 27L. TWR IMMEDIATELY ASKED ME TO EXIT RWY 27L. THE CLRNC WAS TO 'HOLD AT THE HOLD LINE, NOT TO TAXI IN POS AND HOLD.' I APOLOGIZED. I NOW REPEAT ALL CLRNCS RATHER THAN OFFERING A SIMPLE 'ROGER THAT.' SAFETY IN THIS CASE WAS NOT COMPROMISED SINCE NO ACFT WAS ON FINAL APCH. BUT IF THERE HAD BEEN, I MIGHT HAVE CAUSED AN INCIDENT.

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.