Sf-340 landing dfw experienced TCAS RA on runway 31R final.

Attributes
ACN	576597
Time
Date	200303
Day	Fri
Place
Locale Reference	airport : dfw.airport
State Reference	TX
Altitude	msl single value : 4000
Environment
Flight Conditions	VMC
Weather Elements	other
Aircraft 1
Controlling Facilities	tracon : d10.tracon
Operator	common carrier : air carrier
Make Model Name	Saab-Scania Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 31r
Flight Phase	descent : approach
Route In Use	approach : visual approach : instrument non precision
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : d10.tracon
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise : level
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	576597
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne critical non adherence : clearance
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft ATC Human Performance
Primary Problem	Ambiguous

Narrative:

We were on the localizer to runway 31R in dfw at 4000. Conditions were VFR, but hazy as the sun was setting. ATC informed us of traffic below us and we got a visual. I looked at the TCAS and noticed traffic at 4100 ft approaching us at our 1230. I informed ATC, but he said he did not have anyone at that altitude. Within seconds, we received an RA telling us to descend. First officer performed as trained and got us down to avoid the traffic. Our descent rate was 2000 FPM. We leveled at three and let ATC know we had the RA. ATC said there was no traffic at 4100 that would of affected us. We never saw the traffic, but followed the RA. ATC did not further remark other than to remain at 3000 ft, then cleared us for the visual. We landed safely at dfw with no problems from passenger, as they were seated during the RA. No injuries, no complaints!

Original NASA ASRS Text

Title: SF-340 LNDG DFW EXPERIENCED TCAS RA ON RWY 31R FINAL.

Narrative: WE WERE ON THE LOC TO RWY 31R IN DFW AT 4000. CONDITIONS WERE VFR, BUT HAZY AS THE SUN WAS SETTING. ATC INFORMED US OF TFC BELOW US AND WE GOT A VISUAL. I LOOKED AT THE TCAS AND NOTICED TFC AT 4100 FT APCHING US AT OUR 1230. I INFORMED ATC, BUT HE SAID HE DID NOT HAVE ANYONE AT THAT ALT. WITHIN SECONDS, WE RECEIVED AN RA TELLING US TO DSND. FO PERFORMED AS TRAINED AND GOT US DOWN TO AVOID THE TFC. OUR DSCNT RATE WAS 2000 FPM. WE LEVELED AT THREE AND LET ATC KNOW WE HAD THE RA. ATC SAID THERE WAS NO TFC AT 4100 THAT WOULD OF AFFECTED US. WE NEVER SAW THE TFC, BUT FOLLOWED THE RA. ATC DID NOT FURTHER REMARK OTHER THAN TO REMAIN AT 3000 FT, THEN CLRED US FOR THE VISUAL. WE LANDED SAFELY AT DFW WITH NO PROBS FROM PAX, AS THEY WERE SEATED DURING THE RA. NO INJURIES, NO COMPLAINTS!

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.