A boeing 727 flight crew received a TCASII RA while on approach to lga, in N90 class B.

Attributes
ACN	447819
Time
Date	199908
Day	Tue
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : lga.vor
State Reference	NY
Altitude	msl single value : 4500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : n90.tracon tower : btv.tower
Operator	common carrier : air carrier
Make Model Name	B727 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	arrival other
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : n90.tracon
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : commercial pilot : flight engineer pilot : instrument pilot : multi engine
Experience	flight time last 90 days : 110 flight time total : 12000 flight time type : 2490
ASRS Report	447819
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : instrument pilot : commercial
Events
Anomaly	conflict : airborne critical non adherence : required legal separation
Independent Detector	aircraft equipment : tcas other flight crewa other flight crewb
Resolutory Action	controller : issued new clearance flight crew : took precautionary avoidance action
Miss Distance	horizontal : 3000 vertical : 500
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

We were flying up the hudson river, on the river visual runway 13 at lga. Our assigned altitude was 4500 ft MSL. As we were approaching approximately abeam central park, we got a TA, then a TCASII RA for traffic off our left side. We visually acquired the aircraft, an aircraft Y jet twin, probably an airbus. The TCASII indicated it was 500 ft above us. We followed the RA by descending, and I simultaneously announced to new york approach that we were descending, due to the TCASII alert. Approach immediately cleared us to descend to 3500 ft MSL, followed by clearance for the visual approach. I believe the controller simply forgot to descend us to 3500 ft at the normal point on the approach. We had sight of the conflicting traffic, he looked like a definite possibility of conflict, so we followed the RA.

Original NASA ASRS Text

Title: A BOEING 727 FLC RECEIVED A TCASII RA WHILE ON APCH TO LGA, IN N90 CLASS B.

Narrative: WE WERE FLYING UP THE HUDSON RIVER, ON THE RIVER VISUAL RWY 13 AT LGA. OUR ASSIGNED ALT WAS 4500 FT MSL. AS WE WERE APCHING APPROX ABEAM CENTRAL PARK, WE GOT A TA, THEN A TCASII RA FOR TFC OFF OUR L SIDE. WE VISUALLY ACQUIRED THE ACFT, AN ACFT Y JET TWIN, PROBABLY AN AIRBUS. THE TCASII INDICATED IT WAS 500 FT ABOVE US. WE FOLLOWED THE RA BY DSNDING, AND I SIMULTANEOUSLY ANNOUNCED TO NEW YORK APCH THAT WE WERE DSNDING, DUE TO THE TCASII ALERT. APCH IMMEDIATELY CLRED US TO DSND TO 3500 FT MSL, FOLLOWED BY CLRNC FOR THE VISUAL APCH. I BELIEVE THE CTLR SIMPLY FORGOT TO DSND US TO 3500 FT AT THE NORMAL POINT ON THE APCH. WE HAD SIGHT OF THE CONFLICTING TFC, HE LOOKED LIKE A DEFINITE POSSIBILITY OF CONFLICT, SO WE FOLLOWED THE RA.

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.