Narrative:

Approaching augusta bush field, we were cleared direct to emory NDB. We were cleared to 3000 ft then 2000 ft. We called airport in sight at approximately 10 mi out, cleared for the approach and told to switch to tower. The first officer was flying and chose to level at 3000 ft while passing over daniel field. TCASII displayed 2 targets, 1 at 12 O'clock position with no altitude, and 1 at 1 O'clock position indicating +500 ft with no arrow indicating climb or descent. First target initially appeared approximately 5 mi out, second initially appeared at approximately 3 mi out. Neither of us spotted the traffic. We passed the first target. The second target indication went from +500 ft to +200 ft to level with us. (Again with no arrow indicating climb or descent.) by this time, indication showed less than 1 mi from us and gave us an RA telling us to climb. First officer applied maximum power and began climb. RA continued for 10-15 seconds, then ceased. Captain was still on approach control (this was all happening as he told us to switch to bush tower) and told them we had initiated evasive maneuvers based on a TCASII RA. He had been pointing us out to a GA aircraft as traffic, but he said aircraft was not in our vicinity, nor were they painting any traffic in our vicinity. Once RA ceased, we continued approach with no further incident. Called ATC after landing at their request. The captain told them essentially the same as I am reporting here. They said they had 1-2 incidents within the preceding 2-3 days with air carrier aircraft approaching augusta, and they suspected those were also false alarms.

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Original NASA ASRS Text

Title: AN ATR72 FLC PERFORMS AN EVASIVE ACTION CLB IN RESPONSE TO WHAT WAS LATER DEFINED BY ATC AS A FALSE TCASII WARNING ON NON EXISTENT ACFT NEAR DNL, GA.

Narrative: APCHING AUGUSTA BUSH FIELD, WE WERE CLRED DIRECT TO EMORY NDB. WE WERE CLRED TO 3000 FT THEN 2000 FT. WE CALLED ARPT IN SIGHT AT APPROX 10 MI OUT, CLRED FOR THE APCH AND TOLD TO SWITCH TO TWR. THE FO WAS FLYING AND CHOSE TO LEVEL AT 3000 FT WHILE PASSING OVER DANIEL FIELD. TCASII DISPLAYED 2 TARGETS, 1 AT 12 O'CLOCK POS WITH NO ALT, AND 1 AT 1 O'CLOCK POS INDICATING +500 FT WITH NO ARROW INDICATING CLB OR DSCNT. FIRST TARGET INITIALLY APPEARED APPROX 5 MI OUT, SECOND INITIALLY APPEARED AT APPROX 3 MI OUT. NEITHER OF US SPOTTED THE TFC. WE PASSED THE FIRST TARGET. THE SECOND TARGET INDICATION WENT FROM +500 FT TO +200 FT TO LEVEL WITH US. (AGAIN WITH NO ARROW INDICATING CLB OR DSCNT.) BY THIS TIME, INDICATION SHOWED LESS THAN 1 MI FROM US AND GAVE US AN RA TELLING US TO CLB. FO APPLIED MAX PWR AND BEGAN CLB. RA CONTINUED FOR 10-15 SECONDS, THEN CEASED. CAPT WAS STILL ON APCH CTL (THIS WAS ALL HAPPENING AS HE TOLD US TO SWITCH TO BUSH TWR) AND TOLD THEM WE HAD INITIATED EVASIVE MANEUVERS BASED ON A TCASII RA. HE HAD BEEN POINTING US OUT TO A GA ACFT AS TFC, BUT HE SAID ACFT WAS NOT IN OUR VICINITY, NOR WERE THEY PAINTING ANY TFC IN OUR VICINITY. ONCE RA CEASED, WE CONTINUED APCH WITH NO FURTHER INCIDENT. CALLED ATC AFTER LNDG AT THEIR REQUEST. THE CAPT TOLD THEM ESSENTIALLY THE SAME AS I AM RPTING HERE. THEY SAID THEY HAD 1-2 INCIDENTS WITHIN THE PRECEDING 2-3 DAYS WITH ACR ACFT APCHING AUGUSTA, AND THEY SUSPECTED THOSE WERE ALSO FALSE ALARMS.

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.