B767 act on ZNY traffic and TCASII alert for unidentified aircraft operating at 17500 ft.

Attributes
ACN	523854
Time
Date	200109
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : jfk.vor
State Reference	NY
Altitude	msl bound lower : 18500 msl bound upper : 20000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zny.artcc
Operator	common carrier : air carrier
Make Model Name	B767 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	descent : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	controller military : 18 controller radar : 34 flight time last 90 days : 242 flight time total : 11300 flight time type : 2120
ASRS Report	523854
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : undershoot conflict : airborne critical
Independent Detector	atc equipment other atc equipment : radar aircraft equipment : tcas other controllera other flight crewa
Resolutory Action	controller : issued alert flight crew : took precautionary avoidance action flight crew : took evasive action
Miss Distance	horizontal : 0 vertical : 750
Supplementary
Problem Areas	Environmental Factor Flight Crew Human Performance Airspace Structure
Primary Problem	Flight Crew Human Performance

Narrative:

Aircraft was on a regularly scheduled flight to jfk. Takeoff, climb and cruise were normal in all respects. During descent, numerous vectors were given to our aircraft for sequence purposes. Finally, an instruction to fly to camrn (jfk 198 degree radial, 37 DME) and cross at 11000 ft was given to our aircraft. At approximately FL195-FL200, center advised us of 'pop up traffic,' 12 O'clock, 5-10 mi. TCASII immediately advised us with a traffic call. Elevation showed target at 17500 ft. A red RA followed shortly thereafter. We advised center and discontinued the descent. Center said he was not talking to traffic. Both first officer and I spotted target on the nose at about 3-5 mi. He passed below our aircraft. Positive identify of target could not be made by this reporter. No doubt that traffic call by center and TCASII alert, prevented a more nasty situation. This event greatly increased the confidence level this reporter/operator now has for the 'TCASII box.' some additional thoughts: what did we do before TCASII? Should we make the box a 'go' item?

Original NASA ASRS Text

Title: B767 ACT ON ZNY TFC AND TCASII ALERT FOR UNIDENTIFIED ACFT OPERATING AT 17500 FT.

Narrative: ACFT WAS ON A REGULARLY SCHEDULED FLT TO JFK. TKOF, CLB AND CRUISE WERE NORMAL IN ALL RESPECTS. DURING DSCNT, NUMEROUS VECTORS WERE GIVEN TO OUR ACFT FOR SEQUENCE PURPOSES. FINALLY, AN INSTRUCTION TO FLY TO CAMRN (JFK 198 DEG RADIAL, 37 DME) AND CROSS AT 11000 FT WAS GIVEN TO OUR ACFT. AT APPROX FL195-FL200, CTR ADVISED US OF 'POP UP TFC,' 12 O'CLOCK, 5-10 MI. TCASII IMMEDIATELY ADVISED US WITH A TFC CALL. ELEVATION SHOWED TARGET AT 17500 FT. A RED RA FOLLOWED SHORTLY THEREAFTER. WE ADVISED CTR AND DISCONTINUED THE DSCNT. CTR SAID HE WAS NOT TALKING TO TFC. BOTH FO AND I SPOTTED TARGET ON THE NOSE AT ABOUT 3-5 MI. HE PASSED BELOW OUR ACFT. POSITIVE IDENT OF TARGET COULD NOT BE MADE BY THIS RPTR. NO DOUBT THAT TFC CALL BY CTR AND TCASII ALERT, PREVENTED A MORE NASTY SIT. THIS EVENT GREATLY INCREASED THE CONFIDENCE LEVEL THIS RPTR/OPERATOR NOW HAS FOR THE 'TCASII BOX.' SOME ADDITIONAL THOUGHTS: WHAT DID WE DO BEFORE TCASII? SHOULD WE MAKE THE BOX A 'GO' ITEM?

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.