SW3 and an small aircraft have near midair collision below dtw TCA.

Attributes
ACN	343075
Time
Date	199608
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : dtw
State Reference	MI
Altitude	msl bound lower : 2000 msl bound upper : 2250
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dtw
Operator	common carrier : air carrier
Make Model Name	Merlin IIB
Operating Under FAR Part	Part 135
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Flight Plan	None
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : atp
Experience	flight time last 90 days : 250 flight time total : 3950 flight time type : 1486
ASRS Report	343075
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : atp
Experience	flight time last 90 days : 200 flight time total : 4000 flight time type : 700
ASRS Report	343003
Events
Anomaly	conflict : nmac other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 0 vertical : 250
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

We departed off runway 21 with an initial clearance to 4000 ft and heading 280 degrees. Tower requested us to keep the turn inside of the preceding DH8. We had the DH8 in sight and complied. I called for the after takeoff checklist and tower told us to switch to departure. The captain made the switch and we heard departure telling someone about traffic at an unknown altitude. We then noticed the DH8 turning towards us. I slowed the climb to avoid conflict with the DH8. The captain made the call to departure and advised him that we had the DH8 going over top and had leveled at 2000 ft. ATC told us to maintain 2000 ft. Next ATC advised us of traffic at 11-12 O'clock altitude unknown, not talking to anyone, climb and maintain 3000 ft. We started the climb and got the traffic in sight. The traffic was a single engine low wing. At 2300 ft we were converging so I pushed over to descend. The aircraft passed over top of us. At the closest point I would say we were with 250 ft vertical when he went over top of us. We advised ATC of the deviation. He asked us what altitude the aircraft was at and cleared us to 4000 ft. This same aircraft had busted tol airspace and apparently had gotten close to some other aircraft. We continued on to our destination without further incident.

Original NASA ASRS Text

Title: SW3 AND AN SMA HAVE NMAC BELOW DTW TCA.

Narrative: WE DEPARTED OFF RWY 21 WITH AN INITIAL CLRNC TO 4000 FT AND HDG 280 DEGS. TWR REQUESTED US TO KEEP THE TURN INSIDE OF THE PRECEDING DH8. WE HAD THE DH8 IN SIGHT AND COMPLIED. I CALLED FOR THE AFTER TKOF CHKLIST AND TWR TOLD US TO SWITCH TO DEP. THE CAPT MADE THE SWITCH AND WE HEARD DEP TELLING SOMEONE ABOUT TFC AT AN UNKNOWN ALT. WE THEN NOTICED THE DH8 TURNING TOWARDS US. I SLOWED THE CLB TO AVOID CONFLICT WITH THE DH8. THE CAPT MADE THE CALL TO DEP AND ADVISED HIM THAT WE HAD THE DH8 GOING OVER TOP AND HAD LEVELED AT 2000 FT. ATC TOLD US TO MAINTAIN 2000 FT. NEXT ATC ADVISED US OF TFC AT 11-12 O'CLOCK ALT UNKNOWN, NOT TALKING TO ANYONE, CLB AND MAINTAIN 3000 FT. WE STARTED THE CLB AND GOT THE TFC IN SIGHT. THE TFC WAS A SINGLE ENG LOW WING. AT 2300 FT WE WERE CONVERGING SO I PUSHED OVER TO DSND. THE ACFT PASSED OVER TOP OF US. AT THE CLOSEST POINT I WOULD SAY WE WERE WITH 250 FT VERT WHEN HE WENT OVER TOP OF US. WE ADVISED ATC OF THE DEV. HE ASKED US WHAT ALT THE ACFT WAS AT AND CLRED US TO 4000 FT. THIS SAME ACFT HAD BUSTED TOL AIRSPACE AND APPARENTLY HAD GOTTEN CLOSE TO SOME OTHER ACFT. WE CONTINUED ON TO OUR DEST WITHOUT FURTHER INCIDENT.

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.