Narrative:

We were on an extended approach to dca in very poor IMC WX (moderate turbulence, icing, rain) and zero flight visibility. Dca approach control had numerous aircraft in the radar pattern for the ILS to runway 36. We were given several vectors (headings) by ATC, then finally a vector (right turn south) to a 180 degree heading, presumably for downwind. Just as we completed this turn to 180 degrees, the controller gave us a left turn assignment to 090 degrees, basically toward the airport itself. During this turn the controller asked if we were turning to 90 degrees. The first officer responded in the affirmative (we had almost completed the turn), and then asked the controller: 'is there a conflict?' the reverse vectoring (right turn to left turn) seemed unusual to both of us. Approach control never responded to this query. Established on the 090 degree heading, we noticed TCASII traffic south of us at 4-5 mi, at our altitude. We did not get a TA nor an RA warning on the TCASII. We were soon vectored south (180 degrees) again on downwind for 26 mi before being turned on the ILS to runway 36 and landing at dca. Later that evening at our layover hotel, our base duty pilot called me and asked if we had been notified of any conflict or 'near miss' at dca. I replied that we had not, then remembered the unusual vectoring and related it to him. We were, until this time, never notified of any traffic problem. During the entire approach we were on radar vectors given by dca, and on assigned altitude(south). At no time did we receive a TCASII advisory or alert, and until the duty pilot's phone call, were unaware of anything out of the ordinary, save the unusual vectoring.

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Original NASA ASRS Text

Title: AN ACR MD88 FLC WERE VECTORED DOWNWIND THEN IMMEDIATELY TURNED TOWARD THE ARPT THEN TURNED BACK TO DOWNWIND. LATER, THEY WERE CHARGED WITH CAUSING AN NMAC.

Narrative: WE WERE ON AN EXTENDED APCH TO DCA IN VERY POOR IMC WX (MODERATE TURB, ICING, RAIN) AND ZERO FLT VISIBILITY. DCA APCH CTL HAD NUMEROUS ACFT IN THE RADAR PATTERN FOR THE ILS TO RWY 36. WE WERE GIVEN SEVERAL VECTORS (HDGS) BY ATC, THEN FINALLY A VECTOR (R TURN S) TO A 180 DEG HDG, PRESUMABLY FOR DOWNWIND. JUST AS WE COMPLETED THIS TURN TO 180 DEGS, THE CTLR GAVE US A L TURN ASSIGNMENT TO 090 DEGS, BASICALLY TOWARD THE ARPT ITSELF. DURING THIS TURN THE CTLR ASKED IF WE WERE TURNING TO 90 DEGS. THE FO RESPONDED IN THE AFFIRMATIVE (WE HAD ALMOST COMPLETED THE TURN), AND THEN ASKED THE CTLR: 'IS THERE A CONFLICT?' THE REVERSE VECTORING (R TURN TO L TURN) SEEMED UNUSUAL TO BOTH OF US. APCH CTL NEVER RESPONDED TO THIS QUERY. ESTABLISHED ON THE 090 DEG HDG, WE NOTICED TCASII TFC S OF US AT 4-5 MI, AT OUR ALT. WE DID NOT GET A TA NOR AN RA WARNING ON THE TCASII. WE WERE SOON VECTORED S (180 DEGS) AGAIN ON DOWNWIND FOR 26 MI BEFORE BEING TURNED ON THE ILS TO RWY 36 AND LNDG AT DCA. LATER THAT EVENING AT OUR LAYOVER HOTEL, OUR BASE DUTY PLT CALLED ME AND ASKED IF WE HAD BEEN NOTIFIED OF ANY CONFLICT OR 'NEAR MISS' AT DCA. I REPLIED THAT WE HAD NOT, THEN REMEMBERED THE UNUSUAL VECTORING AND RELATED IT TO HIM. WE WERE, UNTIL THIS TIME, NEVER NOTIFIED OF ANY TFC PROB. DURING THE ENTIRE APCH WE WERE ON RADAR VECTORS GIVEN BY DCA, AND ON ASSIGNED ALT(S). AT NO TIME DID WE RECEIVE A TCASII ADVISORY OR ALERT, AND UNTIL THE DUTY PLT'S PHONE CALL, WERE UNAWARE OF ANYTHING OUT OF THE ORDINARY, SAVE THE UNUSUAL VECTORING.

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.