Reported traffic not sighted. TCASII RA warning resulted in 300' climb to avoid traffic.

Attributes
ACN	176267
Time
Date	199104
Day	Sat
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : aqn airport : dfw
State Reference	TX
Altitude	msl bound lower : 9000 msl bound upper : 10600
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dfw artcc : zjx
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	descent other
Route In Use	arrival star : star
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	controller military : 8 controller radar : 19 flight time last 90 days : 150 flight time total : 10000 flight time type : 5000
ASRS Report	176267
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	conflict : airborne less severe
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 500 vertical : 600
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

On approach into dfw, on the aqn two arrival, our TCAS gave an RA signal to pull up. Just before this, approach control gave us a vector, and said, we had VFR traffic at our 2 O'clock position heading west and he was at our altitude. At the time we were descending through 10600' to cross bryar intersection at 9000'. As we pulled up in accordance with TCAS we saw a light twin off our right wing. He went under us as we were passing 11400'. We smoothly pushed over and continued to cross bryar intersection at 9000'. My concern is, why is VFR traffic going over aqn at 10600' which is just about the altitude IFR traffic is when we are descending to make bryar at 9000'. Also ATC pointed the traffic out with no particular urgency. We were not able to acknowledge a contact with the VFR traffic. I would like to see VFR traffic restr from approach corridors.

Original NASA ASRS Text

Title: REPORTED TRAFFIC NOT SIGHTED. TCASII RA WARNING RESULTED IN 300' CLIMB TO AVOID TRAFFIC.

Narrative: ON APCH INTO DFW, ON THE AQN TWO ARR, OUR TCAS GAVE AN RA SIGNAL TO PULL UP. JUST BEFORE THIS, APCH CTL GAVE US A VECTOR, AND SAID, WE HAD VFR TFC AT OUR 2 O'CLOCK POS HDG W AND HE WAS AT OUR ALT. AT THE TIME WE WERE DSNDING THROUGH 10600' TO CROSS BRYAR INTXN AT 9000'. AS WE PULLED UP IN ACCORDANCE WITH TCAS WE SAW A LIGHT TWIN OFF OUR R WING. HE WENT UNDER US AS WE WERE PASSING 11400'. WE SMOOTHLY PUSHED OVER AND CONTINUED TO CROSS BRYAR INTXN AT 9000'. MY CONCERN IS, WHY IS VFR TFC GOING OVER AQN AT 10600' WHICH IS JUST ABOUT THE ALT IFR TFC IS WHEN WE ARE DSNDING TO MAKE BRYAR AT 9000'. ALSO ATC POINTED THE TFC OUT WITH NO PARTICULAR URGENCY. WE WERE NOT ABLE TO ACKNOWLEDGE A CONTACT WITH THE VFR TFC. I WOULD LIKE TO SEE VFR TFC RESTR FROM APCH CORRIDORS.

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.