Narrative:

Runway 29 at sjc has a run-up area across from the parallel taxiway requiring calling ground prior to taxiing to the runway (there is a very limited space from the hold line and the near edge of the taxiway). When ground responded to our request, I misunderstood the instructions and taxied into the 'position and hold' as opposed to up to the 'hold' line. I am not sure the exact phrase used by ground, but it didn't trigger the usual 'hold short' answer back. My response back, in turn, was apparently vaguely worded enough that it was not caught until I was actually on the runway. Tower frequency was monitored as requested and they immediately requested returning to the taxiway. Ground then informed us as to the problem. A phone number was given to contact tower when we reached our destination. We then reentered the runway and departed without incident. Upon reflection, it was obvious that ground cannot give permission to enter the active runway. This specific location has the unusual circumstance where ground must be contacted twice (beginning of taxi, then re-enter the taxiway after run-up) and then wait for tower to call when they are ready to have you enter the active runway. This is compounded by the perception that there isn't really enough room to stop between the parallel taxiway and the hold short line. The tail extends back into or close to the parallel taxiway. No other traffic was near on the ground or arriving to that runway at the time of the incident.

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Original NASA ASRS Text

Title: PLT OF PA46 TAXIES INTO POS ON RWY 29 AT SJC WITHOUT CLRNC. TXWY AND RUN-UP AREA AT APCH END OF RWY 29 IS DESCRIBED AS CONFUSING.

Narrative: RWY 29 AT SJC HAS A RUN-UP AREA ACROSS FROM THE PARALLEL TXWY REQUIRING CALLING GND PRIOR TO TAXIING TO THE RWY (THERE IS A VERY LIMITED SPACE FROM THE HOLD LINE AND THE NEAR EDGE OF THE TXWY). WHEN GND RESPONDED TO OUR REQUEST, I MISUNDERSTOOD THE INSTRUCTIONS AND TAXIED INTO THE 'POS AND HOLD' AS OPPOSED TO UP TO THE 'HOLD' LINE. I AM NOT SURE THE EXACT PHRASE USED BY GND, BUT IT DIDN'T TRIGGER THE USUAL 'HOLD SHORT' ANSWER BACK. MY RESPONSE BACK, IN TURN, WAS APPARENTLY VAGUELY WORDED ENOUGH THAT IT WAS NOT CAUGHT UNTIL I WAS ACTUALLY ON THE RWY. TWR FREQ WAS MONITORED AS REQUESTED AND THEY IMMEDIATELY REQUESTED RETURNING TO THE TXWY. GND THEN INFORMED US AS TO THE PROB. A PHONE NUMBER WAS GIVEN TO CONTACT TWR WHEN WE REACHED OUR DEST. WE THEN REENTERED THE RWY AND DEPARTED WITHOUT INCIDENT. UPON REFLECTION, IT WAS OBVIOUS THAT GND CANNOT GIVE PERMISSION TO ENTER THE ACTIVE RWY. THIS SPECIFIC LOCATION HAS THE UNUSUAL CIRCUMSTANCE WHERE GND MUST BE CONTACTED TWICE (BEGINNING OF TAXI, THEN RE-ENTER THE TXWY AFTER RUN-UP) AND THEN WAIT FOR TWR TO CALL WHEN THEY ARE READY TO HAVE YOU ENTER THE ACTIVE RWY. THIS IS COMPOUNDED BY THE PERCEPTION THAT THERE ISN'T REALLY ENOUGH ROOM TO STOP BTWN THE PARALLEL TXWY AND THE HOLD SHORT LINE. THE TAIL EXTENDS BACK INTO OR CLOSE TO THE PARALLEL TXWY. NO OTHER TFC WAS NEAR ON THE GND OR ARRIVING TO THAT RWY AT THE TIME OF THE 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.