B767 captain reported receiving a false TCAS RA event in the vicinity of ord.

Attributes
ACN	1404441
Time
Date	201611
Local Time Of Day	0601-1200
Place
Locale Reference	C90.TRACON
State Reference	IL
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B767 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	Traffic Collision Avoidance System (TCAS)
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Type 6848
Events
Anomaly	Aircraft Equipment Problem Less Severe

Narrative:

At about two thousand feet; we got a TCAS alert of 'traffic'. It showed to be 100 ft below us and to the right but we saw nothing and had no warning from ATC. We were handed off to departure and just as I called them; got a TCAS RA to 'descend'. I reported this on my initial call to departure and the RA went away at about 2500 ft. We never saw another aircraft and ATC confirmed that no aircraft were near us. The system worked fine on our previous leg and worked properly for the balance of the trip. I assume that this was some anomaly in the ord area; since the TCAS showed all aircraft that we had visually prior to and after this event.

Original NASA ASRS Text

Title: B767 Captain reported receiving a false TCAS RA event in the vicinity of ORD.

Narrative: At about two thousand feet; we got a TCAS alert of 'traffic'. It showed to be 100 ft below us and to the right but we saw nothing and had no warning from ATC. We were handed off to Departure and just as I called them; got a TCAS RA to 'descend'. I reported this on my initial call to Departure and the RA went away at about 2500 ft. We never saw another aircraft and ATC confirmed that no aircraft were near us. The system worked fine on our previous leg and worked properly for the balance of the trip. I assume that this was some anomaly in the ORD area; since the TCAS showed all aircraft that we had visually prior to and after this event.

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.