Narrative:

Our aircraft was at 4000 ft on a vector to a visual approach to runway 15R at bwi. We were cleared to 2500 ft, reported the airport in sight, and were cleared for a visual to runway 15R. At this point, we were on the runway 15L extended centerline, and correcting over to line up with runway 15R. We continued descent for runway 15R, but then observed another aircraft departing on runway 33L (same runway). At this time our heading was 170 degrees, in order to intercept the runway 15R centerline. TCASII then issued a TA for traffic at 10 O'clock, 3 mi. This was followed by an RA to monitor vertical speed, followed by a descend command. We acquired the traffic at 10 O'clock and 1 1/2 mi, at our altitude, and continued descent to 1700 ft on a 170 degree heading to remain clear. Once clear, we advised approach control of our actions, and reasons. We were then given a 180 degree heading and told to maintain 2000 ft. We were then cleared for a visual to runway 33L, and called the tower turning base. The landing was normal. TRACON later said that the TCASII aircraft had departed runway 33R and was given an immediate left turn so as to avoid our path. This put him on a near collision course with us, but we were never advised by approach control. I would recommend closer coordination between tower and approach control (bwi), as well as advisories to inbound traffic concerning traffic about to depart or about to land on the active runways.

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Original NASA ASRS Text

Title: CLOSE PROX OF ACRS ON SAME RWY, OPPOSITE DIRECTION. TCASII RA.

Narrative: OUR ACFT WAS AT 4000 FT ON A VECTOR TO A VISUAL APCH TO RWY 15R AT BWI. WE WERE CLRED TO 2500 FT, RPTED THE ARPT IN SIGHT, AND WERE CLRED FOR A VISUAL TO RWY 15R. AT THIS POINT, WE WERE ON THE RWY 15L EXTENDED CTRLINE, AND CORRECTING OVER TO LINE UP WITH RWY 15R. WE CONTINUED DSCNT FOR RWY 15R, BUT THEN OBSERVED ANOTHER ACFT DEPARTING ON RWY 33L (SAME RWY). AT THIS TIME OUR HDG WAS 170 DEGS, IN ORDER TO INTERCEPT THE RWY 15R CTRLINE. TCASII THEN ISSUED A TA FOR TFC AT 10 O'CLOCK, 3 MI. THIS WAS FOLLOWED BY AN RA TO MONITOR VERT SPD, FOLLOWED BY A DSND COMMAND. WE ACQUIRED THE TFC AT 10 O'CLOCK AND 1 1/2 MI, AT OUR ALT, AND CONTINUED DSCNT TO 1700 FT ON A 170 DEG HDG TO REMAIN CLR. ONCE CLR, WE ADVISED APCH CTL OF OUR ACTIONS, AND REASONS. WE WERE THEN GIVEN A 180 DEG HDG AND TOLD TO MAINTAIN 2000 FT. WE WERE THEN CLRED FOR A VISUAL TO RWY 33L, AND CALLED THE TWR TURNING BASE. THE LNDG WAS NORMAL. TRACON LATER SAID THAT THE TCASII ACFT HAD DEPARTED RWY 33R AND WAS GIVEN AN IMMEDIATE L TURN SO AS TO AVOID OUR PATH. THIS PUT HIM ON A NEAR COLLISION COURSE WITH US, BUT WE WERE NEVER ADVISED BY APCH CTL. I WOULD RECOMMEND CLOSER COORD BTWN TWR AND APCH CTL (BWI), AS WELL AS ADVISORIES TO INBOUND TFC CONCERNING TFC ABOUT TO DEPART OR ABOUT TO LAND ON THE ACTIVE RWYS.

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.