B737-800 first officer reports TCAS RA during descent on the flcon 3 arrival with evasive action tak...

Narrative:

In the descent phase on the flcon 3 RNAV arrival; level at 22;000 feet; TCAS gave a TA but with no target on the navigation display (nd). A few seconds later this turned into an RA commanding a descent of approximately 1500 FPM. The captain was flying and immediately initiated a descent and commanded me to advise ATC; which I did. ATC told us there was no known threat and cleared us to descend to 14;000 feet. In the descent we observed a TCAS RA target on the nd. It was indicating exactly on top of us; no separation; 0 feet altitude difference; and stationary (staying with us). We discussed this briefly and concluded that the RA was obviously a false alarm. We leveled at 14;000 feet and continued inbound; then received a descent to 12;000 feet and turn direct to doevr. We then received another TA followed immediately by an RA and began a second descent at 1400 FPM as commanded. I notified ATC at approximately 11;700 feet MSL and was told that there was no threat observed in our vicinity; but that traffic was climbing up below us and we should not descend below 11;000 feet. We observed again that the TCAS target was exactly on top of us with no separation and co-altitude. The commanded descent was a constant 1400 FPM. We leveled at 11;000 feet and ignored the RA. At doevr we turned westbound and I turned the TCAS to 'TA only.' we continued to receive more false alerts for the remainder of the descent. Following this event the captain phoned the number provided by ATC and was informed that there was no loss of separation between aircraft.

Original NASA ASRS Text

Title: B737-800 First Officer reports TCAS RA during descent on the FLCON 3 arrival with evasive action taken. The target is co-located with the reporter's aircraft laterally and vertically. After further alerts the TCAS is selected to TA only.

Narrative: In the descent phase on the FLCON 3 RNAV arrival; level at 22;000 Feet; TCAS gave a TA but with no target on the navigation display (ND). A few seconds later this turned into an RA commanding a descent of approximately 1500 FPM. The Captain was flying and immediately initiated a descent and commanded me to advise ATC; which I did. ATC told us there was no known threat and cleared us to descend to 14;000 feet. In the descent we observed a TCAS RA target on the ND. It was indicating exactly on top of us; no separation; 0 feet altitude difference; and stationary (staying with us). We discussed this briefly and concluded that the RA was obviously a false alarm. We leveled at 14;000 feet and continued inbound; then received a descent to 12;000 feet and turn direct to DOEVR. We then received another TA followed immediately by an RA and began a second descent at 1400 FPM as commanded. I notified ATC at approximately 11;700 feet MSL and was told that there was no threat observed in our vicinity; but that traffic was climbing up below us and we should not descend below 11;000 feet. We observed again that the TCAS target was exactly on top of us with no separation and co-altitude. The commanded descent was a constant 1400 FPM. We leveled at 11;000 feet and ignored the RA. At DOEVR we turned westbound and I turned the TCAS to 'TA only.' We continued to receive more false alerts for the remainder of the descent. Following this event the Captain phoned the number provided by ATC and was informed that there was no loss of separation between aircraft.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	856130
Time
Date	200910
Local Time Of Day	1201-1800
Place
Locale Reference	ATL.Airport
State Reference	GA
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Make Model Name	B737-800
Operating Under FAR Part	Part 121
Flight Phase	Descent
Route In Use	STAR FLCON3
Flight Plan	IFR
Component
Aircraft Component	TCAS Equipment
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Flight Engineer Flight Crew Flight Instructor
Experience	Flight Crew Last 90 Days 130 Flight Crew Total 8500 Flight Crew Type 2954
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Altitude Excursion From Assigned Altitude

B737-800 first officer reports TCAS RA during descent on the flcon 3 arrival with evasive action taken. The target is co-located with the reporter's aircraft laterally and vertically. After further alerts the TCAS is selected to TA only.