Narrative:

Bos/dca. On ground in bos, taxiing under clearance from gate to runway 9 via txwys K/west/south, hold short of runway 4L, thought cleared across runway 4L and taxied across without clearance to do so.

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Original NASA ASRS Text

Title: AN ACR FLC FLYING A B737-300 AT BOS FAILS TO COMPLY WITH INSTRUCTIONS TO HOLD SHORT OF AN ACTIVE RWY WHILE TAXIING TO THE GATE.

Narrative: BOS/DCA. ON GND IN BOS, TAXIING UNDER CLRNC FROM GATE TO RWY 9 VIA TXWYS K/W/S, HOLD SHORT OF RWY 4L, THOUGHT CLRED ACROSS RWY 4L AND TAXIED ACROSS WITHOUT CLRNC TO DO SO.

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.