Narrative:

During vector to final runway 17C we acknowledged contact with traffic at 1 O'clock position that was landing on the right runway (runway 18R). We were landing runway 17C. We were told to maintain 4000 ft until intercepting final and we were cleared for the visual. While descending on intercept to final, RA alerted us to climb. The brasilia passed 300 ft below us to land on runway 17L. We climbed and then descended for normal landing. Approach should have told us the traffic would be flying under us. Maintaining altitude 'until intercepting final' is too nebulous. He should have had us intercept the localizer then descend instead of trying to cram as many aircraft into the pattern as possible. Approach should not so gladly grant visuals, ie, it's better to hold an aircraft at an altitude and don't grant the visual until certain the 2 aircraft will not descend on top of each other. Finally, clearing aircraft over the top of each other at 500 ft for crisscrossing final approachs with only 500 ft vertical clearance should be stopped immediately.

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Original NASA ASRS Text

Title: AN NMAC OCCURS 11 MI N OF DFW WHEN AN EMB120 UNEXPECTEDLY CROSSES 300 FT BENEATH AN MD88 WHO IS DSNDING FOR APCH TO RWY 17C. THE BRASILIA WAS GIVEN AS TFC BY APCH FOR RWY 18R. THE MD88 WAS TO MAINTAIN 4000 FT UNTIL 'INTERCEPTING FINAL.'

Narrative: DURING VECTOR TO FINAL RWY 17C WE ACKNOWLEDGED CONTACT WITH TFC AT 1 O'CLOCK POS THAT WAS LNDG ON THE R RWY (RWY 18R). WE WERE LNDG RWY 17C. WE WERE TOLD TO MAINTAIN 4000 FT UNTIL INTERCEPTING FINAL AND WE WERE CLRED FOR THE VISUAL. WHILE DSNDING ON INTERCEPT TO FINAL, RA ALERTED US TO CLB. THE BRASILIA PASSED 300 FT BELOW US TO LAND ON RWY 17L. WE CLBED AND THEN DSNDED FOR NORMAL LNDG. APCH SHOULD HAVE TOLD US THE TFC WOULD BE FLYING UNDER US. MAINTAINING ALT 'UNTIL INTERCEPTING FINAL' IS TOO NEBULOUS. HE SHOULD HAVE HAD US INTERCEPT THE LOC THEN DSND INSTEAD OF TRYING TO CRAM AS MANY ACFT INTO THE PATTERN AS POSSIBLE. APCH SHOULD NOT SO GLADLY GRANT VISUALS, IE, IT'S BETTER TO HOLD AN ACFT AT AN ALT AND DON'T GRANT THE VISUAL UNTIL CERTAIN THE 2 ACFT WILL NOT DSND ON TOP OF EACH OTHER. FINALLY, CLRING ACFT OVER THE TOP OF EACH OTHER AT 500 FT FOR CRISSCROSSING FINAL APCHS WITH ONLY 500 FT VERT CLRNC SHOULD BE STOPPED IMMEDIATELY.

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.