An L1011 flight crew became confused taxiing at lax during the morning rush.

Attributes
ACN	455100
Time
Date	199911
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lax.airport
State Reference	CA
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Dawn
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	L-1011 Tri-Star All Series
Operating Under FAR Part	Part 121
Flight Phase	ground : taxi
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tower : lax.tower
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	ground : taxi
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : atp
Experience	flight time last 90 days : 210 flight time total : 5700 flight time type : 2000
ASRS Report	455100
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : ground less severe other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Supplementary
Problem Areas	Airport
Primary Problem	Airport

Narrative:

On taxi outbound from lax clearance was to 'pass behind aircraft Y, a B757.' taxiway C (inner) was blocked due to construction to the west and blocked east due to aircraft Y, the B757 holding for a gate. Aircraft Z, a B737, was blocking taxiway B (outer). The aircraft Y was passing right to left (eastbound) on taxiway B (outer). Our aircraft taxied out of the alley at taxiway C8 and held short of taxiway B. Our understanding was to wait for aircraft to pass and follow. Ground asked 'who is L1011 on taxiway C at C8 without clearance?' we gave call sign then were told to taxi in front of aircraft Y, the B757, then turned into taxiway C at C8 to follow aircraft Z. This was very unclr since aircraft Y was unable to taxi on taxiway C due to aircraft Z. We assumed that they would stay on taxiway B and we would follow. Taxi instructions should be more clear specifically when aircraft are holding on txwys and there is major construction in the area.

Original NASA ASRS Text

Title: AN L1011 FLC BECAME CONFUSED TAXIING AT LAX DURING THE MORNING RUSH.

Narrative: ON TAXI OUTBOUND FROM LAX CLRNC WAS TO 'PASS BEHIND ACFT Y, A B757.' TXWY C (INNER) WAS BLOCKED DUE TO CONSTRUCTION TO THE W AND BLOCKED E DUE TO ACFT Y, THE B757 HOLDING FOR A GATE. ACFT Z, A B737, WAS BLOCKING TXWY B (OUTER). THE ACFT Y WAS PASSING R TO L (EBOUND) ON TXWY B (OUTER). OUR ACFT TAXIED OUT OF THE ALLEY AT TXWY C8 AND HELD SHORT OF TXWY B. OUR UNDERSTANDING WAS TO WAIT FOR ACFT TO PASS AND FOLLOW. GND ASKED 'WHO IS L1011 ON TXWY C AT C8 WITHOUT CLRNC?' WE GAVE CALL SIGN THEN WERE TOLD TO TAXI IN FRONT OF ACFT Y, THE B757, THEN TURNED INTO TXWY C AT C8 TO FOLLOW ACFT Z. THIS WAS VERY UNCLR SINCE ACFT Y WAS UNABLE TO TAXI ON TXWY C DUE TO ACFT Z. WE ASSUMED THAT THEY WOULD STAY ON TXWY B AND WE WOULD FOLLOW. TAXI INSTRUCTIONS SHOULD BE MORE CLR SPECIFICALLY WHEN ACFT ARE HOLDING ON TXWYS AND THERE IS MAJOR CONSTRUCTION IN THE AREA.

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.