Narrative:

Stl airport approximately 600 ft MSL. A good round number for altitude based on distance from the field, 300 ft per NM to allow for a normal maneuver to land. There were simultaneous runway 30L lda/DME and runway 30R ILS approachs in use. We were being vectored to join the runway 30L lda/DME localizer in VFR conditions at 4500 ft MSL about 10-12 mi out (typically, stl approach would have us at 3500 ft MSL by this point). While on a heading to join the localizer, we were turned away from the intercept (more perpendicular to the course), but not specifically told not to join the localizer. As the intercept came in, we clarified and continued on the assigned heading. We were almost immediately turned back to join the localizer from the other side. While in this turn, approach gave us a discretionary descent to 2100 ft MSL, and asked us if we had traffic at our 12 O'clock position, 2 1/2 mi, 500 ft below us. We did not have them, but we did have a target on our TCASII less than 2 mi and 500-600 ft below us which was giving us a TA. If we had begun our discretionary descent, it would have been an RA. Once on the lda localizer, we were told to follow traffic for the visual. This traffic was approximately 2 mi from us lined up with the runway, we were on the lda localizer and thus 2 mi apart, but not 2 mi in trail of an aircraft we had never acknowledged having insight. After a brief analysis, we abandoned the approach as unreasonable, unsafe and having been unnecessarily been put in a bad sot by ATC even to have just gone in to land. In the ensuing vectors back around to land, ATC missed handing us off to tower, so we just switched over when bout on a 3 mi final to the assigned runway.

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Original NASA ASRS Text

Title: BAE146 CREW LNDG STL ARE VECTORED TO FOLLOW TFC ON FINAL THAT RESULTS IN A MISSED APCH BECAUSE OF SPACING.

Narrative: STL ARPT APPROX 600 FT MSL. A GOOD ROUND NUMBER FOR ALT BASED ON DISTANCE FROM THE FIELD, 300 FT PER NM TO ALLOW FOR A NORMAL MANEUVER TO LAND. THERE WERE SIMULTANEOUS RWY 30L LDA/DME AND RWY 30R ILS APCHS IN USE. WE WERE BEING VECTORED TO JOIN THE RWY 30L LDA/DME LOC IN VFR CONDITIONS AT 4500 FT MSL ABOUT 10-12 MI OUT (TYPICALLY, STL APCH WOULD HAVE US AT 3500 FT MSL BY THIS POINT). WHILE ON A HDG TO JOIN THE LOC, WE WERE TURNED AWAY FROM THE INTERCEPT (MORE PERPENDICULAR TO THE COURSE), BUT NOT SPECIFICALLY TOLD NOT TO JOIN THE LOC. AS THE INTERCEPT CAME IN, WE CLARIFIED AND CONTINUED ON THE ASSIGNED HDG. WE WERE ALMOST IMMEDIATELY TURNED BACK TO JOIN THE LOC FROM THE OTHER SIDE. WHILE IN THIS TURN, APCH GAVE US A DISCRETIONARY DSCNT TO 2100 FT MSL, AND ASKED US IF WE HAD TFC AT OUR 12 O'CLOCK POS, 2 1/2 MI, 500 FT BELOW US. WE DID NOT HAVE THEM, BUT WE DID HAVE A TARGET ON OUR TCASII LESS THAN 2 MI AND 500-600 FT BELOW US WHICH WAS GIVING US A TA. IF WE HAD BEGUN OUR DISCRETIONARY DSCNT, IT WOULD HAVE BEEN AN RA. ONCE ON THE LDA LOC, WE WERE TOLD TO FOLLOW TFC FOR THE VISUAL. THIS TFC WAS APPROX 2 MI FROM US LINED UP WITH THE RWY, WE WERE ON THE LDA LOC AND THUS 2 MI APART, BUT NOT 2 MI IN TRAIL OF AN ACFT WE HAD NEVER ACKNOWLEDGED HAVING INSIGHT. AFTER A BRIEF ANALYSIS, WE ABANDONED THE APCH AS UNREASONABLE, UNSAFE AND HAVING BEEN UNNECESSARILY BEEN PUT IN A BAD SOT BY ATC EVEN TO HAVE JUST GONE IN TO LAND. IN THE ENSUING VECTORS BACK AROUND TO LAND, ATC MISSED HANDING US OFF TO TWR, SO WE JUST SWITCHED OVER WHEN BOUT ON A 3 MI FINAL TO THE ASSIGNED RWY.

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.