Narrative:

On departure climb from kmsy; we were cleared from FL340 to FL360. At FL355; captain (flying) pointed out a TCAS target slightly behind (less than 1 mile) and exactly at our cleared altitude of FL360 on both nds. No TCAS RA was received; so he asked me to confirm with center if there was an aircraft at our cleared altitude. ATC didn't hear my initial transmission; as I believe the hand mike cord came out of the socket as I grabbed the hand-held mike. Meanwhile; the captain stopped the climb momentarily at FL355 as ATC asked if we were level yet at FL360. I attempted confirmation again that there was no aircraft at FL360; while the captain disconnected the autopilot and auto-thrust to keep the aircraft level at about FL355. At this time; ATC directed us to turn right immediately 30 degrees and had another aircraft that wasn't initially on our TCAS; but was climbing to FL350; then descend to FL340. I don't know if that aircraft received a TCAS RA; but I re-established communication with my headset and confirmed we had turned 30 degrees right and were at FL355. ATC asked if we were maneuvering for a TCAS RA; which we weren't. ATC didn't mention any loss of separation; but subsequently cleared us the block FL350-360 momentarily as we assessed the situation. At that time; we both noticed 'TA only' on our nds; even though traffic mode was selected. We also knew this aircraft had been written up the previous day for this same malfunction (without the phantom targets). Captain then re-selected auto-flight and leveled at FL360.

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Original NASA ASRS Text

Title: A320 First Officer reported receiving a TCAS warning for what was apparently a phantom target.

Narrative: On departure climb from KMSY; we were cleared from FL340 to FL360. At FL355; Captain (flying) pointed out a TCAS target slightly behind (less than 1 mile) and exactly at our cleared altitude of FL360 on both NDs. No TCAS RA was received; so he asked me to confirm with Center if there was an aircraft at our cleared altitude. ATC didn't hear my initial transmission; as I believe the hand mike cord came out of the socket as I grabbed the hand-held mike. Meanwhile; the Captain stopped the climb momentarily at FL355 as ATC asked if we were level yet at FL360. I attempted confirmation again that there was no aircraft at FL360; while the Captain disconnected the autopilot and auto-thrust to keep the aircraft level at about FL355. At this time; ATC directed us to turn right immediately 30 degrees and had another aircraft that wasn't initially on our TCAS; but was climbing to FL350; then descend to FL340. I don't know if that aircraft received a TCAS RA; but I re-established communication with my headset and confirmed we had turned 30 degrees right and were at FL355. ATC asked if we were maneuvering for a TCAS RA; which we weren't. ATC didn't mention any loss of separation; but subsequently cleared us the block FL350-360 momentarily as we assessed the situation. At that time; we both noticed 'TA ONLY' on our NDs; even though traffic mode was selected. We also knew this aircraft had been written up the previous day for this same malfunction (without the phantom targets). Captain then re-selected auto-flight and leveled at FL360.

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.