Air carrier on downwind with tower to call base has TCASII RA with opposite direction traffic.

Attributes
ACN	277793
Time
Date	199407
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : lex
State Reference	KY
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : lex
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	enroute : 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 other
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 190 flight time total : 5300 flight time type : 2000
ASRS Report	277793
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	non adherence : published procedure non adherence : far other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 5500
Supplementary
Primary Problem	Ambiguous
Air Traffic Incident	Pilot Deviation

Narrative:

We saw airport about 6 mi (southeast) out. ATC advised us to continue downwind he would call our base leg, we had traffic on final we were to follow. We continued on downwind. Then the TCASII called 'traffic, traffic, monitor vertical speed.' the traffic was less than 5 mi same altitude opposite direction. Now the approach controller told us we had traffic at 12 O'clock 3 mi but by this time the only thing left to do was to bank hard to the left. I entered a 60-70 degree bank. On the ground I asked tower if the traffic watch aircraft we had to avoid was in the class C airspace he said he did not know he would check. I think if we were given a little sooner warning about the traffic watch aircraft it could have avoided the excessive bank angle. We did get within a mi of this aircraft.

Original NASA ASRS Text

Title: ACR ON DOWNWIND WITH TWR TO CALL BASE HAS TCASII RA WITH OPPOSITE DIRECTION TFC.

Narrative: WE SAW ARPT ABOUT 6 MI (SE) OUT. ATC ADVISED US TO CONTINUE DOWNWIND HE WOULD CALL OUR BASE LEG, WE HAD TFC ON FINAL WE WERE TO FOLLOW. WE CONTINUED ON DOWNWIND. THEN THE TCASII CALLED 'TFC, TFC, MONITOR VERT SPD.' THE TFC WAS LESS THAN 5 MI SAME ALT OPPOSITE DIRECTION. NOW THE APCH CTLR TOLD US WE HAD TFC AT 12 O'CLOCK 3 MI BUT BY THIS TIME THE ONLY THING LEFT TO DO WAS TO BANK HARD TO THE LEFT. I ENTERED A 60-70 DEG BANK. ON THE GND I ASKED TWR IF THE TFC WATCH ACFT WE HAD TO AVOID WAS IN THE CLASS C AIRSPACE HE SAID HE DID NOT KNOW HE WOULD CHK. I THINK IF WE WERE GIVEN A LITTLE SOONER WARNING ABOUT THE TFC WATCH ACFT IT COULD HAVE AVOIDED THE EXCESSIVE BANK ANGLE. WE DID GET WITHIN A MI OF THIS ACFT.

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.