Air carrier X TCASII RA with probable VFR cessna. See and avoid concept. Evasive action taken.

Attributes
ACN	323230
Time
Date	199512
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : tri
State Reference	TN
Altitude	msl bound lower : 6800 msl bound upper : 6800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : tri
Operator	common carrier : air carrier
Make Model Name	ATR 72
Operating Under FAR Part	Part 121
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Cessna Single Piston Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 5000 flight time type : 1500
ASRS Report	323230
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 23000 flight time type : 150
ASRS Report	323310
Events
Anomaly	conflict : airborne less severe non adherence : published procedure
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 3000 vertical : 100
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

Air carrier X. On descent and approach into tri-city airport, we were assigned turn to 360 degrees and cleared to descend to 6000 ft for landing runway 5. Received RA on traffic to climb and discontinued descent to begin climb. Shortly after we observed single engine aircraft passing approximately 100-200 ft below our altitude about 2500-3000 ft to our left. Approach control then advised us to maintain 7000 ft and pilot called traffic to approach and they verified that we had been initially cleared to descend to 6000 ft.

Original NASA ASRS Text

Title: ACR X TCASII RA WITH PROBABLE VFR CESSNA. SEE AND AVOID CONCEPT. EVASIVE ACTION TAKEN.

Narrative: ACR X. ON DSCNT AND APCH INTO TRI-CITY ARPT, WE WERE ASSIGNED TURN TO 360 DEGS AND CLRED TO DSND TO 6000 FT FOR LNDG RWY 5. RECEIVED RA ON TFC TO CLB AND DISCONTINUED DSCNT TO BEGIN CLB. SHORTLY AFTER WE OBSERVED SINGLE ENG ACFT PASSING APPROX 100-200 FT BELOW OUR ALT ABOUT 2500-3000 FT TO OUR L. APCH CTL THEN ADVISED US TO MAINTAIN 7000 FT AND PLT CALLED TFC TO APCH AND THEY VERIFIED THAT WE HAD BEEN INITIALLY CLRED TO DSND TO 6000 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.