Narrative:

On assigned heading of 090 degrees to intercept milton 8 arrival between nanci and proud intxns (lga 225 degrees radial). Cleared from 9000-7000 ft in descent at approximately 8000 ft. Received RA on TCASII command climb. Climbed to 8000 ft when I saw cessna 1XX sbound at approximately 7500 ft 1/4 to 1/2 mi to left. At that time lga approach called traffic at 10-11 O'clock at 7400 ft. After cessna passed to south, I continued descent to 7000 ft. I do not believe other aircraft saw us at any time. He appeared to be at a legal VFR altitude. Maneuver to arrest descent (1000 FPM) and climb back to approximately 8000 ft was without disturbance in cabin. Incident lasted 15-20 seconds. ATC was advised of 'RA.' no comment received. Continued vectors to approach and land on runway 13 at lga at approximately XA06 local. I don't know of anything we could have done to avoid the incident. TCASII helped avoid a potentially catastrophic incident.

Google
 

Original NASA ASRS Text

Title: RPTR ALERTED BY TCASII RA SEES AND AVOIDS POTENTIAL CONFLICT WHILE ON RADAR VECTOR TO LGA.

Narrative: ON ASSIGNED HDG OF 090 DEGS TO INTERCEPT MILTON 8 ARR BTWN NANCI AND PROUD INTXNS (LGA 225 DEGS RADIAL). CLRED FROM 9000-7000 FT IN DSCNT AT APPROX 8000 FT. RECEIVED RA ON TCASII COMMAND CLB. CLBED TO 8000 FT WHEN I SAW CESSNA 1XX SBOUND AT APPROX 7500 FT 1/4 TO 1/2 MI TO L. AT THAT TIME LGA APCH CALLED TFC AT 10-11 O'CLOCK AT 7400 FT. AFTER CESSNA PASSED TO S, I CONTINUED DSCNT TO 7000 FT. I DO NOT BELIEVE OTHER ACFT SAW US AT ANY TIME. HE APPEARED TO BE AT A LEGAL VFR ALT. MANEUVER TO ARREST DSCNT (1000 FPM) AND CLB BACK TO APPROX 8000 FT WAS WITHOUT DISTURBANCE IN CABIN. INCIDENT LASTED 15-20 SECONDS. ATC WAS ADVISED OF 'RA.' NO COMMENT RECEIVED. CONTINUED VECTORS TO APCH AND LAND ON RWY 13 AT LGA AT APPROX XA06 LCL. I DON'T KNOW OF ANYTHING WE COULD HAVE DONE TO AVOID THE INCIDENT. TCASII HELPED AVOID A POTENTIALLY CATASTROPHIC INCIDENT.

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.