Narrative:

Ont, taxiing from our gate to runway 8L. Just prior to taxiway F, controller said 'aircraft X, taxi into position and hold.' first reaction is to trust a controller and turn onto that taxiway. The end of the runway was obscured from that point. At that point as we jogged in the taxiway, we looked up and saw aircraft Y lifting off -- a serious problem. While appearing on the 10-9 chart to be straight, taxiway 1 jogs at several points prior to reaching taxiway 2. Controller did not say taxi into position and hold at taxiway 2 or at the end, etc.

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Original NASA ASRS Text

Title: A B733 CREW, WHILE TAXIING UNDER LIMITED VISIBILITY CONDITIONS AT ONT, MISTOOK A TXWY AS THE DEP END OF THE RWY.

Narrative: ONT, TAXIING FROM OUR GATE TO RWY 8L. JUST PRIOR TO TXWY F, CTLR SAID 'ACFT X, TAXI INTO POS AND HOLD.' FIRST REACTION IS TO TRUST A CTLR AND TURN ONTO THAT TXWY. THE END OF THE RWY WAS OBSCURED FROM THAT POINT. AT THAT POINT AS WE JOGGED IN THE TXWY, WE LOOKED UP AND SAW ACFT Y LIFTING OFF -- A SERIOUS PROB. WHILE APPEARING ON THE 10-9 CHART TO BE STRAIGHT, TXWY 1 JOGS AT SEVERAL POINTS PRIOR TO REACHING TXWY 2. CTLR DID NOT SAY TAXI INTO POS AND HOLD AT TXWY 2 OR AT THE END, ETC.

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.