Air carrier vectored through localizer course, then back on course. Has TCASII TA's then RA.

Attributes
ACN	181611
Time
Date	199106
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : dtw
State Reference	MI
Altitude	msl bound lower : 3000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dtw
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 13000 flight time type : 6000
ASRS Report	181611
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne less severe non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 5000 vertical : 0
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	other

Narrative:

While being vectored by approach control to runway 21R, approach controller vectored me through 21R localizer. When I was about 1/2 mi south of the localizer, the controller instructed me to turn right to 240 degrees and join the 21R localizer. Shortly after this the controller asked me if I saw the airport. I said, 'yes.' he then issued me an unrequested visibility approach. Shortly after this I got the first TA from TCAS. The first officer and I immediately began searching for the conflict. I think I got perhaps 1 or 2 more TA's before I got the RA. It instructed me to climb and called for at least 2000 FPM. I complied with the RA and climbed straight ahead more or less on the 21R localizer to 4000' MSL. The TCAS when instructed me to 'monitor vertical speed.' I was still about 8 1/2 mi northeast of metropolitan and more or less on the localizer. I looked to my left. At this time I observed an air carrier small transport immediately to my left, banking away from me and perhaps less than 1 mi away. I landed normally, completed all checklists and taxied to the gate. I think that sloppy controling was partially to blame. TCAS operates within very defined parameters. I believe that by the controller vectoring me through the 21R localizer and perhaps the air carrier small transport overshooting also brought us close together. Maybe west/O TCAS I would have never seen the other aircraft, but TCAS saw the other aircraft.

Original NASA ASRS Text

Title: ACR VECTORED THROUGH LOCALIZER COURSE, THEN BACK ON COURSE. HAS TCASII TA'S THEN RA.

Narrative: WHILE BEING VECTORED BY APCH CTL TO RWY 21R, APCH CTLR VECTORED ME THROUGH 21R LOC. WHEN I WAS ABOUT 1/2 MI S OF THE LOC, THE CTLR INSTRUCTED ME TO TURN RIGHT TO 240 DEGS AND JOIN THE 21R LOC. SHORTLY AFTER THIS THE CTLR ASKED ME IF I SAW THE ARPT. I SAID, 'YES.' HE THEN ISSUED ME AN UNREQUESTED VIS APCH. SHORTLY AFTER THIS I GOT THE FIRST TA FROM TCAS. THE F/O AND I IMMEDIATELY BEGAN SEARCHING FOR THE CONFLICT. I THINK I GOT PERHAPS 1 OR 2 MORE TA'S BEFORE I GOT THE RA. IT INSTRUCTED ME TO CLB AND CALLED FOR AT LEAST 2000 FPM. I COMPLIED WITH THE RA AND CLBED STRAIGHT AHEAD MORE OR LESS ON THE 21R LOC TO 4000' MSL. THE TCAS WHEN INSTRUCTED ME TO 'MONITOR VERT SPD.' I WAS STILL ABOUT 8 1/2 MI NE OF METRO AND MORE OR LESS ON THE LOC. I LOOKED TO MY LEFT. AT THIS TIME I OBSERVED AN ACR SMT IMMEDIATELY TO MY LEFT, BANKING AWAY FROM ME AND PERHAPS LESS THAN 1 MI AWAY. I LANDED NORMALLY, COMPLETED ALL CHKLISTS AND TAXIED TO THE GATE. I THINK THAT SLOPPY CTLING WAS PARTIALLY TO BLAME. TCAS OPERATES WITHIN VERY DEFINED PARAMETERS. I BELIEVE THAT BY THE CTLR VECTORING ME THROUGH THE 21R LOC AND PERHAPS THE ACR SMT OVERSHOOTING ALSO BROUGHT US CLOSE TOGETHER. MAYBE W/O TCAS I WOULD HAVE NEVER SEEN THE OTHER ACFT, BUT TCAS SAW THE OTHER ACFT.

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.