B190 crew had a tcasi TA with a DC9 in mke class C airspace.

Attributes
ACN	476207
Time
Date	200006
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : mke.airport
State Reference	WI
Altitude	msl bound lower : 2800 msl bound upper : 8000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : mke.tracon
Operator	common carrier : air carrier
Make Model Name	Beech 1900
Operating Under FAR Part	Part 121
Flight Phase	descent : vacating altitude
Route In Use	arrival : on vectors
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : mke.tracon
Operator	common carrier : air carrier
Make Model Name	DC-9 30
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial pilot : cfi
Experience	flight time last 90 days : 250 flight time total : 5500 flight time type : 700
ASRS Report	476207
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation non adherence : far other anomaly other
Independent Detector	aircraft equipment : tcas other flight crewa other flight crewb
Resolutory Action	none taken : anomaly accepted
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	FAA ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error
Situations
ATC Facility	staffing : mke.tracon

Narrative:

I was the PF. We were on vectors for descent into mke. ATC cleared us from 8000 ft to 6000 ft. We were approximately 10 mi southeast of the airport on about a 340 degree heading. ATC then cleared us to 2800 ft and asked if we had the airport in sight. (At this point we were descending through approximately 7000 ft.) the captain replied that we did. ATC then told us the instructions were not for us but a different aircraft. At this time we received a TA on tcasi. We had visual contact with the other aircraft which was approximately 2-4 mi ahead of us crossing our left to right departing from mke. No evasive action was needed. ATC said we were answering for the wrong aircraft and were never cleared from 8000 ft. The captain and I, however, were sure he was using our call sign and the mistake was his. (He meant to say a different call sign). This was confirmed after we landed and the captain talked to him on the phone. The controller said he listened back to the tapes and he was in fact using our call sign when he actually meant to be talking to a different aircraft (same company). I believe the controller made the mistake because he was overloaded. This was evident as we were approaching the airport. The traffic volume was busy and you could tell from the urgency in his voice, not only to us but all of the traffic he was communicating with, that he was handling all of the traffic that he could.

Original NASA ASRS Text

Title: B190 CREW HAD A TCASI TA WITH A DC9 IN MKE CLASS C AIRSPACE.

Narrative: I WAS THE PF. WE WERE ON VECTORS FOR DSCNT INTO MKE. ATC CLRED US FROM 8000 FT TO 6000 FT. WE WERE APPROX 10 MI SE OF THE ARPT ON ABOUT A 340 DEG HDG. ATC THEN CLRED US TO 2800 FT AND ASKED IF WE HAD THE ARPT IN SIGHT. (AT THIS POINT WE WERE DSNDING THROUGH APPROX 7000 FT.) THE CAPT REPLIED THAT WE DID. ATC THEN TOLD US THE INSTRUCTIONS WERE NOT FOR US BUT A DIFFERENT ACFT. AT THIS TIME WE RECEIVED A TA ON TCASI. WE HAD VISUAL CONTACT WITH THE OTHER ACFT WHICH WAS APPROX 2-4 MI AHEAD OF US XING OUR L TO R DEPARTING FROM MKE. NO EVASIVE ACTION WAS NEEDED. ATC SAID WE WERE ANSWERING FOR THE WRONG ACFT AND WERE NEVER CLRED FROM 8000 FT. THE CAPT AND I, HOWEVER, WERE SURE HE WAS USING OUR CALL SIGN AND THE MISTAKE WAS HIS. (HE MEANT TO SAY A DIFFERENT CALL SIGN). THIS WAS CONFIRMED AFTER WE LANDED AND THE CAPT TALKED TO HIM ON THE PHONE. THE CTLR SAID HE LISTENED BACK TO THE TAPES AND HE WAS IN FACT USING OUR CALL SIGN WHEN HE ACTUALLY MEANT TO BE TALKING TO A DIFFERENT ACFT (SAME COMPANY). I BELIEVE THE CTLR MADE THE MISTAKE BECAUSE HE WAS OVERLOADED. THIS WAS EVIDENT AS WE WERE APCHING THE ARPT. THE TFC VOLUME WAS BUSY AND YOU COULD TELL FROM THE URGENCY IN HIS VOICE, NOT ONLY TO US BUT ALL OF THE TFC HE WAS COMMUNICATING WITH, THAT HE WAS HANDLING ALL OF THE TFC THAT HE COULD.

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.