B727 taxiing for departure at lax crossed departure runway without clearance.

Attributes
ACN	582345
Time
Date	200305
Day	Tue
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : lax.airport
State Reference	CA
Altitude	agl single value : 0
Environment
Flight Conditions	IMC
Light	Dawn
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B727 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 : atp
Experience	flight time last 90 days : 80 flight time total : 9500 flight time type : 650
ASRS Report	582345
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	incursion : runway non adherence : far non adherence : clearance
Resolutory Action	controller : issued new clearance
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were cleared (I thought) to cross runway 25L and cleared to take off on runway 25R at taxiway F. The captain was taxiing after crossing runway 25L as if we were going to cross runway 25R at taxiway F and go to the end for takeoff. I said that we were cleared to take off at taxiway F, but he said I was wrong and that we should go across and use full length. After we crossed runway 25R at taxiway F, tower's wording indicated what I thought was right and we were cleared to take off at runway 25R at taxiway F, but to now go the end and position and hold. After he crossed, he admitted I was right, after he heard the tower.

Original NASA ASRS Text

Title: B727 TAXIING FOR DEP AT LAX CROSSED DEP RWY WITHOUT CLRNC.

Narrative: WE WERE CLRED (I THOUGHT) TO CROSS RWY 25L AND CLRED TO TAKE OFF ON RWY 25R AT TXWY F. THE CAPT WAS TAXIING AFTER XING RWY 25L AS IF WE WERE GOING TO CROSS RWY 25R AT TXWY F AND GO TO THE END FOR TKOF. I SAID THAT WE WERE CLRED TO TAKE OFF AT TXWY F, BUT HE SAID I WAS WRONG AND THAT WE SHOULD GO ACROSS AND USE FULL LENGTH. AFTER WE CROSSED RWY 25R AT TXWY F, TWR'S WORDING INDICATED WHAT I THOUGHT WAS RIGHT AND WE WERE CLRED TO TAKE OFF AT RWY 25R AT TXWY F, BUT TO NOW GO THE END AND POS AND HOLD. AFTER HE CROSSED, HE ADMITTED I WAS RIGHT, AFTER HE HEARD THE TWR.

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.