Flight crew receives TCASII RA alert.

Attributes
ACN	547944
Time
Date	200205
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : hpn.airport
State Reference	NY
Altitude	msl bound lower : 2500 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : n90.tracon
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	cruise : level descent : approach
Route In Use	approach : traffic pattern
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : n90.tracon
Operator	general aviation : personal
Make Model Name	Cessna Single Piston Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 8500 flight time type : 4500
ASRS Report	547944
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : nmac
Independent Detector	aircraft equipment : tcas other controllera other flight crewa other flight crewb
Resolutory Action	controller : issued alert controller : issued new clearance flight crew : returned to assigned altitude flight crew : took evasive action
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	ATC Human Performance

Narrative:

On downwind to runway 34 at hpn, under ATC control, controller told us of light aircraft traffic at 12 O'clock position. He then gave us a turn to 100 degrees to avoid traffic. Just after initiating turn, we got a TA, then an RA to descend immediately. Cessna traffic passed 300 ft overhead. Our aircraft leveled at 2500 ft. Approach was notified of RA and we returned to 3000 ft.

Original NASA ASRS Text

Title: FLC RECEIVES TCASII RA ALERT.

Narrative: ON DOWNWIND TO RWY 34 AT HPN, UNDER ATC CTL, CTLR TOLD US OF LIGHT ACFT TFC AT 12 O'CLOCK POS. HE THEN GAVE US A TURN TO 100 DEGS TO AVOID TFC. JUST AFTER INITIATING TURN, WE GOT A TA, THEN AN RA TO DSND IMMEDIATELY. CESSNA TFC PASSED 300 FT OVERHEAD. OUR ACFT LEVELED AT 2500 FT. APCH WAS NOTIFIED OF RA AND WE RETURNED TO 3000 FT.

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.