AN AT72 COMMUTER FO RPTS RESPONDING TO A TCASII RA WHILE 5 NM NW OF THE DFW CLASS B AIRSPACE. RPTR COMPLAINS ABOUT THE NEW ATC PROCS REQUIRING TURBOPROPS TO DSND TO BTWN 6000 FT AND 7000 FT; 70 NM OUT FROM DFW.

Narrative

WHILE ON BOWIE 1 ARR TO DFW; APCH HAD CLRED US TO MAINTAIN 6000 FT. CREW OBSERVED TCASII TFC AT 2 O'CLOCK; 5 MI; 500 FT ABOVE; AND DSNDING. DFW APCH CALLED THE TFC AND CREW ACKNOWLEDGED VISUAL CONTACT. TCASII GAVE A TA FOLLOWED BY AN RA 'DSND; DSND' WITH A 1500 FPM DSCNT RATE COMMAND. CREW INITIATED DSCNT AS DFW APCH CLRED FLT TO DSND TO 5000 FT MSL. CAUSE OF PROB: DFW APCH REQUIRES ARRIVING TURBOPROP ACR ACFT TO BE AT 6000-7000 FT OVER 70 NM FROM HUB. THIS CAUSES ACFT TO ENTER CLASS B AIRSPACE FROM THE SIDE INSTEAD OF THE TOP. IT PUTS THE ACR ACFT ON A PERPENDICULAR COURSE TO GA ACFT AS THE GA ACFT CIRCUMNAV THE CLASS B. THIS NMAC OCCURRED 5 NM OUTSIDE OF CLASS B. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ADDS THAT THE VFR TFC CIRCUMNAVING THE AIRSPACE ABOVE 3000 FT AGL MAY OR MAY NOT BE FLYING AT APPROPRIATE ALTS FOR THE DIRECTION OF FLT. IF THESE ACFT ARE CHANGING ALTS TO ADJUST FOR THE DIRECTION OF FLT; THEN THEY MAY BE DSNDING OR CLBING THROUGH A 1000 FT ALT AT JUST ABOUT THE TIME THAT AN ACR ACFT IS INBOUND FROM ONE OF THE DFW 'CORNER POSTS' (IN THIS INCIDENT; BOWIE VOR).