B737 crew had TCASII RA in N90 class B airspace.

Attributes
ACN	490829
Time
Date	200009
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : lga.airport
State Reference	NY
Altitude	msl single value : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	descent : vacating altitude
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : n90.tracon
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 151 flight time total : 19830 flight time type : 4395
ASRS Report	490829
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : commercial pilot : cfi pilot : instrument
Experience	flight time last 90 days : 200 flight time total : 4000 flight time type : 700
ASRS Report	485030
Events
Anomaly	conflict : airborne critical conflict : nmac non adherence : published procedure non adherence : far
Independent Detector	aircraft equipment : tcas other controllera other flight crewa other flight crewb
Resolutory Action	controller : issued alert flight crew : took evasive action
Miss Distance	vertical : 300
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance Company Airspace Structure
Primary Problem	ATC Human Performance

Narrative:

This occurred at XA20 while on left base for runway 22 at lga, altitude 3000 ft MSL. We responded to TCASII RA as well as an ATC traffic alert. Intruder aircraft was directly below us. Do not know type. We never saw the aircraft visually or on the TCASII until we received the RA which showed 300 ft vertical separation. We climbed to and leveled at 6000 ft MSL and received the 'clear of conflict' message. In my opinion, ATC was overloaded. Too much traffic to work at one time.

Original NASA ASRS Text

Title: B737 CREW HAD TCASII RA IN N90 CLASS B AIRSPACE.

Narrative: THIS OCCURRED AT XA20 WHILE ON L BASE FOR RWY 22 AT LGA, ALT 3000 FT MSL. WE RESPONDED TO TCASII RA AS WELL AS AN ATC TFC ALERT. INTRUDER ACFT WAS DIRECTLY BELOW US. DO NOT KNOW TYPE. WE NEVER SAW THE ACFT VISUALLY OR ON THE TCASII UNTIL WE RECEIVED THE RA WHICH SHOWED 300 FT VERT SEPARATION. WE CLBED TO AND LEVELED AT 6000 FT MSL AND RECEIVED THE 'CLR OF CONFLICT' MESSAGE. IN MY OPINION, ATC WAS OVERLOADED. TOO MUCH TFC TO WORK AT ONE TIME.

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.