Flight crew of A320 taxiing to runway 24L at lax misunderstood clearance to perform a 180 degrees an...

Attributes
ACN	607431
Time
Date	200402
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : lax.airport
State Reference	CA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	ground : taxi ground : holding
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 210 flight time total : 8500 flight time type : 2500
ASRS Report	607431
Person 2
Affiliation	company : air carrier
Function	flight crew : captain
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance
Supplementary
Problem Areas	Flight Crew Human Performance Airport ATC Human Performance
Primary Problem	Ambiguous

Narrative:

We were on our taxi to runway 24L at lax. As we were approaching the departure end of the runway, tower instructed us to do a 180 degree turn and hold short of taxiway V facing west. We interpreted this as a 180 degree turn on E7 (which we thought was 'the concrete pad'). Just before we entered E7, we questioned the taxi instructions from tower and indeed we misunderstood the taxi instructions from tower. We held our position with no incursion on any active runway. Tower gave us new taxi instructions onto runway 24L and we departed. Because we questioned the taxi instructions and held our position before proceeding, we did not incur on any active taxiway or runway. I feel that the 'concrete pad' in lax at the departure end of runway 24L should be clearly labeled on the airport diagram. I believe this would prevent future confusion at this area of lax. Callback conversation with reporter revealed the follwoing information: the reporter reinforced the analyst's interpretation of what took place and where. The only new information gained was that the reporter was the PIC flying from the right seat while performing IOE training of a new captain.

Original NASA ASRS Text

Title: FLT CREW OF A320 TAXIING TO RWY 24L AT LAX MISUNDERSTOOD CLRNC TO PERFORM A 180 DEGS AND HOLD SHORT OF TXWY V FACING W. ASKED FOR CLARIFICATION BEFORE AN INCURSION TOOK PLACE ON E7.

Narrative: WE WERE ON OUR TAXI TO RWY 24L AT LAX. AS WE WERE APCHING THE DEP END OF THE RWY, TWR INSTRUCTED US TO DO A 180 DEG TURN AND HOLD SHORT OF TXWY V FACING W. WE INTERPRETED THIS AS A 180 DEG TURN ON E7 (WHICH WE THOUGHT WAS 'THE CONCRETE PAD'). JUST BEFORE WE ENTERED E7, WE QUESTIONED THE TAXI INSTRUCTIONS FROM TWR AND INDEED WE MISUNDERSTOOD THE TAXI INSTRUCTIONS FROM TWR. WE HELD OUR POS WITH NO INCURSION ON ANY ACTIVE RWY. TWR GAVE US NEW TAXI INSTRUCTIONS ONTO RWY 24L AND WE DEPARTED. BECAUSE WE QUESTIONED THE TAXI INSTRUCTIONS AND HELD OUR POS BEFORE PROCEEDING, WE DID NOT INCUR ON ANY ACTIVE TXWY OR RWY. I FEEL THAT THE 'CONCRETE PAD' IN LAX AT THE DEP END OF RWY 24L SHOULD BE CLRLY LABELED ON THE ARPT DIAGRAM. I BELIEVE THIS WOULD PREVENT FUTURE CONFUSION AT THIS AREA OF LAX. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLWOING INFO: THE RPTR REINFORCED THE ANALYST'S INTERP OF WHAT TOOK PLACE AND WHERE. THE ONLY NEW INFO GAINED WAS THAT THE RPTR WAS THE PIC FLYING FROM THE R SEAT WHILE PERFORMING IOE TRAINING OF A NEW CAPT.

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.

Flight crew of A320 taxiing to runway 24L at lax misunderstood clearance to perform a 180 degrees and hold short of taxiway V facing west. Asked for clarification before an incursion took place on E7.