Narrative:

Bos tower cleared us into position and hold. During the reading of the lineup checklist, tower called again. The first officer just coming off a 4 month medical leave didn't hear the call. I replied back 'clear for takeoff.' we completed the checklist and began takeoff roll. Meanwhile another aircraft was on takeoff roll from T intersection runway 22L at bos. I saw other aircraft after approximately 200 ft of takeoff roll and aborted takeoff roll. Through a phone conversation we figured that the 2 aircraft did not get closer than 4000 ft and my transmission of 'clear for takeoff' was either blocked or unreadable.

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Original NASA ASRS Text

Title: TKOF ABORTED IN A NIGHT OP.

Narrative: BOS TWR CLRED US INTO POS AND HOLD. DURING THE READING OF THE LINEUP CHKLIST, TWR CALLED AGAIN. THE FO JUST COMING OFF A 4 MONTH MEDICAL LEAVE DIDN'T HEAR THE CALL. I REPLIED BACK 'CLR FOR TKOF.' WE COMPLETED THE CHKLIST AND BEGAN TKOF ROLL. MEANWHILE ANOTHER ACFT WAS ON TKOF ROLL FROM T INTXN RWY 22L AT BOS. I SAW OTHER ACFT AFTER APPROX 200 FT OF TKOF ROLL AND ABORTED TKOF ROLL. THROUGH A PHONE CONVERSATION WE FIGURED THAT THE 2 ACFT DID NOT GET CLOSER THAN 4000 FT AND MY XMISSION OF 'CLR FOR TKOF' WAS EITHER BLOCKED OR UNREADABLE.

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.