A319 flight crew reported they received an erroneous RA from a malfunctioning TCAS unit.

Attributes
ACN	1401265
Time
Date	201611
Local Time Of Day	0601-1200
Place
Locale Reference	FLL.Airport
State Reference	FL
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	A319
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Component
Aircraft Component	Traffic Collision Avoidance System (TCAS)
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Not Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe

Narrative:

We were told to cross mosie at 250 and 8000. Just prior to leveling off at 8000 and a few miles from mosie we received an RA to descend. I clicked off the autopilot and began to descend in the green zone of the vsi. The captain advised ATC we were complying with an RA. ATC advised there were no targets near us but the TCAS read there was a plane right on top of us. The RA continued for a decent amount of time until I started to feel that something wasn't correct I leveled off at 6000 the target never changed its relative altitude or location from us. We switched the TCAS off then back on rapidly and the RA disappeared. We advised ATC we were level at 6000 and they said to maintain that alt. We went below the restriction at mosie. A few minutes later in the flight we received another RA with a target right on top of us. We looked; saw no danger; and recycled the TCAS and the target was gone. The TCAS was written up in fll. The unit must have been faulty.

Original NASA ASRS Text

Title: A319 flight crew reported they received an erroneous RA from a malfunctioning TCAS unit.

Narrative: We were told to cross MOSIE at 250 and 8000. Just prior to leveling off at 8000 and a few miles from MOSIE we received an RA to descend. I clicked off the autopilot and began to descend in the green zone of the VSI. The captain advised ATC we were complying with an RA. ATC advised there were no targets near us but the TCAS read there was a plane right on top of us. The RA continued for a decent amount of time until I started to feel that something wasn't correct I leveled off at 6000 the target never changed its relative altitude or location from us. We switched the TCAS off then back on rapidly and the RA disappeared. We advised ATC we were level at 6000 and they said to maintain that alt. We went below the restriction at MOSIE. A few minutes later in the flight we received another RA with a target right on top of us. We looked; saw no danger; and recycled the TCAS and the target was gone. The TCAS was written up in FLL. The unit must have been faulty.

Data retrieved from NASA's ASRS site 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.