TCASII RA aids in avoidance of pop-up traffic during approach to bdl, ct.

Attributes
ACN	468590
Time
Date	200004
Day	Sat
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : bdl.airport
State Reference	CT
Altitude	msl bound lower : 8500 msl bound upper : 9000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	MD-88
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : intermediate altitude
Route In Use	arrival : on vectors
Flight Plan	IFR
Aircraft 2
Operator	Other
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : atp
Experience	flight time last 90 days : 200 flight time total : 20000
ASRS Report	468590
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : multi engine pilot : instrument
Events
Anomaly	conflict : airborne critical
Resolutory Action	flight crew : took evasive action
Miss Distance	vertical : 1000
Supplementary
Problem Areas	Flight Crew Human Performance Airspace Structure ATC Human Performance
Primary Problem	Airspace Structure

Narrative:

Inbound to bdl about 30 mi southwest in the vicinity of mad VOR we had been cleared to descend to 5000 ft. Through approximately 8900 ft we received a TA on TCASII. We saw a target at about 3-4 mi 900 ft below us. At 8500 ft I clicked off autoplt and leveled at 8500 ft, we had no visual on the traffic, approximately 2 seconds later we got an RA to climb at 2000 FPM. I immediately applied climb thrust and pitched to 10 degrees up. Almost immediately ATC (bdl approach) called and reported pop-up traffic and gave us the option of rapid descent or climb. We were already climbing and at 9000 ft the warning changed to 'monitor vertical speed.' I leveled at 9000 ft and the TCASII reported 'clear of conflict.' the first officer reported that he saw the traffic go below, possibly a cessna 172 approximately 1000 ft. We then continued descent and normal approach and landing at bdl.

Original NASA ASRS Text

Title: TCASII RA AIDS IN AVOIDANCE OF POP-UP TFC DURING APCH TO BDL, CT.

Narrative: INBOUND TO BDL ABOUT 30 MI SW IN THE VICINITY OF MAD VOR WE HAD BEEN CLRED TO DSND TO 5000 FT. THROUGH APPROX 8900 FT WE RECEIVED A TA ON TCASII. WE SAW A TARGET AT ABOUT 3-4 MI 900 FT BELOW US. AT 8500 FT I CLICKED OFF AUTOPLT AND LEVELED AT 8500 FT, WE HAD NO VISUAL ON THE TFC, APPROX 2 SECONDS LATER WE GOT AN RA TO CLB AT 2000 FPM. I IMMEDIATELY APPLIED CLB THRUST AND PITCHED TO 10 DEGS UP. ALMOST IMMEDIATELY ATC (BDL APCH) CALLED AND RPTED POP-UP TFC AND GAVE US THE OPTION OF RAPID DSCNT OR CLB. WE WERE ALREADY CLBING AND AT 9000 FT THE WARNING CHANGED TO 'MONITOR VERT SPD.' I LEVELED AT 9000 FT AND THE TCASII RPTED 'CLR OF CONFLICT.' THE FO RPTED THAT HE SAW THE TFC GO BELOW, POSSIBLY A CESSNA 172 APPROX 1000 FT. WE THEN CONTINUED DSCNT AND NORMAL APCH AND LNDG AT BDL.

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.