Medium large transport has near midair collision on descent.

Attributes
ACN	277202
Time
Date	199407
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : etx
State Reference	PA
Altitude	msl bound lower : 10500 msl bound upper : 10500
Environment
Flight Conditions	Marginal
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent other
Route In Use	enroute : on vectors enroute airway : zny
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	other : unknown
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : commercial pilot : atp pilot : instrument
Experience	flight time last 90 days : 220 flight time total : 9700 flight time type : 2500
ASRS Report	277202
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : commercial pilot : instrument
Events
Anomaly	conflict : nmac non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera
Resolutory Action	other
Consequence	Other
Miss Distance	horizontal : 500 vertical : 100
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

ZNY issued a descent to 9000 ft from 13000 ft, advised to turn to heading 100 degrees for IFR traffic. Further advised of VFR traffic reported but not confirmed to be at 10500 ft 2 O'clock 4 mi headed wbound. Picked up VFR aircraft on TCASII at apparent altitude of 10500 ft. Heading assigned by controller appeared to take us right into traffic. I slowed descent and continued turn past 100 degrees and stopped descent. First officer picked up aircraft coming out of clouds close aboard. I executed turn back to left to avoid further conflict. The controller should not have issued a descent into a VFR aircraft he was not talking to. This aircraft should not have been on a VFR flight plan in marginal conditions. I should have maintained assigned heading and stopped descent sooner to avoid conflict. Important lesson -- you cannot make horizontal evasive maneuvers based on TCASII screen.

Original NASA ASRS Text

Title: MLG HAS NMAC ON DSCNT.

Narrative: ZNY ISSUED A DSCNT TO 9000 FT FROM 13000 FT, ADVISED TO TURN TO HDG 100 DEGS FOR IFR TFC. FURTHER ADVISED OF VFR TFC RPTED BUT NOT CONFIRMED TO BE AT 10500 FT 2 O'CLOCK 4 MI HEADED WBOUND. PICKED UP VFR ACFT ON TCASII AT APPARENT ALT OF 10500 FT. HDG ASSIGNED BY CTLR APPEARED TO TAKE US RIGHT INTO TFC. I SLOWED DSCNT AND CONTINUED TURN PAST 100 DEGS AND STOPPED DSCNT. FO PICKED UP ACFT COMING OUT OF CLOUDS CLOSE ABOARD. I EXECUTED TURN BACK TO L TO AVOID FURTHER CONFLICT. THE CTLR SHOULD NOT HAVE ISSUED A DSCNT INTO A VFR ACFT HE WAS NOT TALKING TO. THIS ACFT SHOULD NOT HAVE BEEN ON A VFR FLT PLAN IN MARGINAL CONDITIONS. I SHOULD HAVE MAINTAINED ASSIGNED HDG AND STOPPED DSCNT SOONER TO AVOID CONFLICT. IMPORTANT LESSON -- YOU CANNOT MAKE HORIZ EVASIVE MANEUVERS BASED ON TCASII SCREEN.

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.