Narrative:

Holding short of 30L at romeo, we were instructed by ATC to taxi into position and hold. After crossing the hold short line, we were instructed to hold short of 30L again. As there was an large transport in position for takeoff at the end of 30L and a widebody transport on final for 30L, my first officer questioned the tower about our proximity to the runway. The tower controller said something to the effect that our position was ok. After the departure of the large transport, I backed the aircraft to the correct side of the hold short line to increase our distance from the landing widebody transport. This incident is currently being investigated by the FAA for illegal aircraft backing contrary to company G.O.M. (I.e., no wing walkers). Supplemental information from acn 170969: ATC cleared us into position on the runway and approximately 10 seconds later cancelled this clearance and advised us to hold short. We were still past the hold short line and in order to avoid a possible conflict the captain elected to use reverse power to back the aircraft up approximately 20' to the hold short line. The underlying cause of this situation was the poor planning utilized by ATC in clearing our aircraft into position when inadequate time existed to clear 2 aircraft for takeoff before the widebody transport reached the runway.

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Original NASA ASRS Text

Title: LTT BACKS BEHIND HOLD SHORT LINE ILLEGALLY.

Narrative: HOLDING SHORT OF 30L AT ROMEO, WE WERE INSTRUCTED BY ATC TO TAXI INTO POS AND HOLD. AFTER XING THE HOLD SHORT LINE, WE WERE INSTRUCTED TO HOLD SHORT OF 30L AGAIN. AS THERE WAS AN LGT IN POS FOR TKOF AT THE END OF 30L AND A WDB ON FINAL FOR 30L, MY F/O QUESTIONED THE TWR ABOUT OUR PROX TO THE RWY. THE TWR CTLR SAID SOMETHING TO THE EFFECT THAT OUR POS WAS OK. AFTER THE DEP OF THE LGT, I BACKED THE ACFT TO THE CORRECT SIDE OF THE HOLD SHORT LINE TO INCREASE OUR DISTANCE FROM THE LNDG WDB. THIS INCIDENT IS CURRENTLY BEING INVESTIGATED BY THE FAA FOR ILLEGAL ACFT BACKING CONTRARY TO COMPANY G.O.M. (I.E., NO WING WALKERS). SUPPLEMENTAL INFO FROM ACN 170969: ATC CLRED US INTO POS ON THE RWY AND APPROX 10 SECS LATER CANCELLED THIS CLRNC AND ADVISED US TO HOLD SHORT. WE WERE STILL PAST THE HOLD SHORT LINE AND IN ORDER TO AVOID A POSSIBLE CONFLICT THE CAPT ELECTED TO USE REVERSE PWR TO BACK THE ACFT UP APPROX 20' TO THE HOLD SHORT LINE. THE UNDERLYING CAUSE OF THIS SITUATION WAS THE POOR PLANNING UTILIZED BY ATC IN CLRING OUR ACFT INTO POS WHEN INADEQUATE TIME EXISTED TO CLR 2 ACFT FOR TKOF BEFORE THE WDB REACHED THE RWY.

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.