Narrative:

We taxied to the departure end of runway 25L from FBO as cleared by lax ground control. We were held there for 5 to 6 mins. The tower then cleared us to 'taxi full length and hold.' we readback same and taxied into position on the runway and held. About 20 to 30 seconds later we were cleared to 'turn right, taxi and hold short of runway 25R,' which we did. We were then cleared to cross runway 25R, taxi to runway 25R and we departed runway 25R. About 30 mins into the flight we were told to call lax tower, which we did upon arrival at destination. We were informed that the 'taxi full length and hold' clearance was not a clearance to taxi into position and hold. Since we were already at the departure end of the runway and we were not told to 'taxi up to and hold short of the runway' we understood the 'taxi full length and hold' as a clearance to taxi into position at the full length of the runway and hold. The tower supervisor informed us that because the clearance was missing a runway assignment, that it was not a clearance to taxi onto the runway. Had a clearance to 'taxi up to and hold short of the runway' been issued, we would not have taxied into position on the runway. This clearance, however, requires a full readback and may increase congestion on the frequency. Thankfully no other aircraft were involved and the controller quickly directed us off the runway. I have never received one before but if I ever receive a 'taxi full length and hold' clearance again while holding at the departure end of a runway, I will query the controller as to his exact intentions.

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Original NASA ASRS Text

Title: IFR C750 TAXIED ONTO RWY 25L AT LAX AFTER CONFUSED CTLR PHRASEOLOGY.

Narrative: WE TAXIED TO THE DEP END OF RWY 25L FROM FBO AS CLRED BY LAX GND CTL. WE WERE HELD THERE FOR 5 TO 6 MINS. THE TWR THEN CLRED US TO 'TAXI FULL LENGTH AND HOLD.' WE READBACK SAME AND TAXIED INTO POS ON THE RWY AND HELD. ABOUT 20 TO 30 SECONDS LATER WE WERE CLRED TO 'TURN R, TAXI AND HOLD SHORT OF RWY 25R,' WHICH WE DID. WE WERE THEN CLRED TO CROSS RWY 25R, TAXI TO RWY 25R AND WE DEPARTED RWY 25R. ABOUT 30 MINS INTO THE FLT WE WERE TOLD TO CALL LAX TWR, WHICH WE DID UPON ARR AT DEST. WE WERE INFORMED THAT THE 'TAXI FULL LENGTH AND HOLD' CLRNC WAS NOT A CLRNC TO TAXI INTO POS AND HOLD. SINCE WE WERE ALREADY AT THE DEP END OF THE RWY AND WE WERE NOT TOLD TO 'TAXI UP TO AND HOLD SHORT OF THE RWY' WE UNDERSTOOD THE 'TAXI FULL LENGTH AND HOLD' AS A CLRNC TO TAXI INTO POS AT THE FULL LENGTH OF THE RWY AND HOLD. THE TWR SUPVR INFORMED US THAT BECAUSE THE CLRNC WAS MISSING A RWY ASSIGNMENT, THAT IT WAS NOT A CLRNC TO TAXI ONTO THE RWY. HAD A CLRNC TO 'TAXI UP TO AND HOLD SHORT OF THE RWY' BEEN ISSUED, WE WOULD NOT HAVE TAXIED INTO POS ON THE RWY. THIS CLRNC, HOWEVER, REQUIRES A FULL READBACK AND MAY INCREASE CONGESTION ON THE FREQ. THANKFULLY NO OTHER ACFT WERE INVOLVED AND THE CTLR QUICKLY DIRECTED US OFF THE RWY. I HAVE NEVER RECEIVED ONE BEFORE BUT IF I EVER RECEIVE A 'TAXI FULL LENGTH AND HOLD' CLRNC AGAIN WHILE HOLDING AT THE DEP END OF A RWY, I WILL QUERY THE CTLR AS TO HIS EXACT INTENTIONS.

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.