Descending medium large transport has near midair collision with small transport.

Attributes
ACN	106142
Time
Date	198903
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : vny airport : bur
State Reference	CA
Altitude	msl bound lower : 6500 msl bound upper : 6500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : bur
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	cruise other
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : commercial pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 200 flight time total : 8000 flight time type : 1700
ASRS Report	106142
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	conflict : nmac
Independent Detector	other controllera other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 350
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

During IFR descent into bur autoplt in VMC conditions we were advised of several traffic targets. We saw some. The target of near collision was told to us when about 8 mi at 1-2 O'clock at around our altitude. We were descending at 200 KIAS out of 6500' to 6000' MSL (assigned) on a heading of 105 degrees. At this time we saw the conflicting aircraft at 12-1 O'clock at our altitude. We saw aircraft when approximately 1 mi or less. I disconnected autoplt and increased my rate of descent as I felt other aircraft was slightly above us. When we passed it was directly overhead 200-500' at most. I feel the controller should have given us another warning after the first one at 8 mi. It must have been apparent to her that the aircraft was still in conflict. I don't think a controller should assume the conflicting aircraft is no factor just because no mode C transponder. The other aircraft was a light (white, tan?) colored light twin. This aircraft appeared on a 310 degree heading. I called the bur approach control supervisor and reported the incident. I think all aircraft flying in high density areas such as bur should have operating mode C (altitude reporting) xponders.

Original NASA ASRS Text

Title: DESCENDING MLG HAS NMAC WITH SMT.

Narrative: DURING IFR DSCNT INTO BUR AUTOPLT IN VMC CONDITIONS WE WERE ADVISED OF SEVERAL TFC TARGETS. WE SAW SOME. THE TARGET OF NEAR COLLISION WAS TOLD TO US WHEN ABOUT 8 MI AT 1-2 O'CLOCK AT AROUND OUR ALT. WE WERE DSNDING AT 200 KIAS OUT OF 6500' TO 6000' MSL (ASSIGNED) ON A HDG OF 105 DEGS. AT THIS TIME WE SAW THE CONFLICTING ACFT AT 12-1 O'CLOCK AT OUR ALT. WE SAW ACFT WHEN APPROX 1 MI OR LESS. I DISCONNECTED AUTOPLT AND INCREASED MY RATE OF DSCNT AS I FELT OTHER ACFT WAS SLIGHTLY ABOVE US. WHEN WE PASSED IT WAS DIRECTLY OVERHEAD 200-500' AT MOST. I FEEL THE CTLR SHOULD HAVE GIVEN US ANOTHER WARNING AFTER THE FIRST ONE AT 8 MI. IT MUST HAVE BEEN APPARENT TO HER THAT THE ACFT WAS STILL IN CONFLICT. I DON'T THINK A CTLR SHOULD ASSUME THE CONFLICTING ACFT IS NO FACTOR JUST BECAUSE NO MODE C XPONDER. THE OTHER ACFT WAS A LIGHT (WHITE, TAN?) COLORED LIGHT TWIN. THIS ACFT APPEARED ON A 310 DEG HDG. I CALLED THE BUR APCH CTL SUPVR AND RPTED THE INCIDENT. I THINK ALL ACFT FLYING IN HIGH DENSITY AREAS SUCH AS BUR SHOULD HAVE OPERATING MODE C (ALT RPTING) XPONDERS.

Data retrieved from NASA's ASRS site as of August 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.