C172 pilot followed the wrong traffic pointed out by ATC at azo, twice.

Attributes
ACN	530499
Time
Date	200111
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : azo.airport
State Reference	MI
Altitude	msl single value : 2500
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	tracon : azo.tracon
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	cruise : level descent : approach
Route In Use	enroute : on vectors
Flight Plan	None
Aircraft 2
Controlling Facilities	tracon : azo.tracon
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	descent : approach
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 12 flight time total : 590 flight time type : 200
ASRS Report	530499
Person 2
Function	observation : passenger
Events
Anomaly	non adherence : published procedure non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : separated traffic controller : issued alert controller : issued new clearance flight crew : became reoriented
Supplementary
Problem Areas	ATC Human Performance Airport Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was returning from the southwest with my wife (a student pilot) who was talking and communicating with ATC as I flew and watched for traffic, which was heavy at that time. ATC vectored us to a heading of 310 degrees and advised us of other traffic near us and someone overtaking us from the right. A few mins later we were cleared as #3 for the right base for runway 17 and the traffic we were following was at our 12 O'clock position and 2 mi. We spotted what we thought to be the traffic and started in a northeast direction. About 15 seconds later, ATC queried our direction. We told her northeast and she responded that we were supposed to be on 310 degree heading and make an immediate turn to 270 degrees and follow that traffic. We spotted a plane heading north with no other visible traffic and responded 'traffic in sight.' we were then instructed to make an immediate emergency climb and the traffic we were following was not the plane ATC wanted us to follow. We were then instructed to fly heading 090 degrees and contact tower. We did, and were told to land 230 degrees, not 170 degrees. There was a lot of confusion on the radios. ATC was issuing a lot of clrncs very rapidly. Some people would not respond. ATC was getting stepped on and the ground lights and strobes of the city at dusk made identing targets very difficult. I think the extra workload on ATC allowed this situation to develop as well as the confusion created in the air. We were having a difficult time getting a break on the radio to question ATC. Additional controller and radio frequency could have reduced this confusion and potential problem.

Original NASA ASRS Text

Title: C172 PLT FOLLOWED THE WRONG TFC POINTED OUT BY ATC AT AZO, TWICE.

Narrative: I WAS RETURNING FROM THE SW WITH MY WIFE (A STUDENT PLT) WHO WAS TALKING AND COMMUNICATING WITH ATC AS I FLEW AND WATCHED FOR TFC, WHICH WAS HVY AT THAT TIME. ATC VECTORED US TO A HDG OF 310 DEGS AND ADVISED US OF OTHER TFC NEAR US AND SOMEONE OVERTAKING US FROM THE R. A FEW MINS LATER WE WERE CLRED AS #3 FOR THE R BASE FOR RWY 17 AND THE TFC WE WERE FOLLOWING WAS AT OUR 12 O'CLOCK POS AND 2 MI. WE SPOTTED WHAT WE THOUGHT TO BE THE TFC AND STARTED IN A NE DIRECTION. ABOUT 15 SECONDS LATER, ATC QUERIED OUR DIRECTION. WE TOLD HER NE AND SHE RESPONDED THAT WE WERE SUPPOSED TO BE ON 310 DEG HDG AND MAKE AN IMMEDIATE TURN TO 270 DEGS AND FOLLOW THAT TFC. WE SPOTTED A PLANE HDG N WITH NO OTHER VISIBLE TFC AND RESPONDED 'TFC IN SIGHT.' WE WERE THEN INSTRUCTED TO MAKE AN IMMEDIATE EMER CLB AND THE TFC WE WERE FOLLOWING WAS NOT THE PLANE ATC WANTED US TO FOLLOW. WE WERE THEN INSTRUCTED TO FLY HDG 090 DEGS AND CONTACT TWR. WE DID, AND WERE TOLD TO LAND 230 DEGS, NOT 170 DEGS. THERE WAS A LOT OF CONFUSION ON THE RADIOS. ATC WAS ISSUING A LOT OF CLRNCS VERY RAPIDLY. SOME PEOPLE WOULD NOT RESPOND. ATC WAS GETTING STEPPED ON AND THE GND LIGHTS AND STROBES OF THE CITY AT DUSK MADE IDENTING TARGETS VERY DIFFICULT. I THINK THE EXTRA WORKLOAD ON ATC ALLOWED THIS SIT TO DEVELOP AS WELL AS THE CONFUSION CREATED IN THE AIR. WE WERE HAVING A DIFFICULT TIME GETTING A BREAK ON THE RADIO TO QUESTION ATC. ADDITIONAL CTLR AND RADIO FREQ COULD HAVE REDUCED THIS CONFUSION AND POTENTIAL PROB.

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.