Narrative:

During initial climb, TCASII gave us a TA at 11:30 to 12 O'clock and 2 mi, same altitude. Out of 11200 ft (approximately) we received an RA to 'descend.' ATC had only 'unverified' traffic and apparently did not have time to respond to our request for a vector away from the traffic. TCASII then commanded 'increase descent.' we attempted to comply with the RA and never did reach the green area even though we were doing maximum rate of descent (5000 to 8000 FPM down). During this evasive maneuver, we exceeded vmo by 20 to 25 KTS. Upon visually contacting the alert aircraft, it was apparent to both the first officer and myself that the proper maneuver would have been to climb above the traffic. We never did hear 'clear of conflict.' we also exceeded 250 KIAS below 10000 ft in this evasive maneuver. I think the A320 TCASII display is faulty. Callback conversation with reporter revealed the following information: reporter's comment, 'I think the A320 TCASII display is faulty', is because the reporter believes the RA commanded excessive descent (5000 to 8000 FPM) and during the maneuver the analog vertical speed scale showed solid red. Then, when acquiring the intruder aircraft visually, the flight crew's consensus was that the RA should have commanded a climb instead of descent. Reporter's aircraft was climbing through 11200 ft and later the FAA tape review showed the intruder to be a cessna 172 at 11500 ft. Thus, the command to descend was appropriate. However, reporter had just received the traffic advisory from ATC, and reporter had requested a turn. Just at that time the RA commanded 'increase descent' and reporter commenced descent (the descent command had already been given, but reporter preferred to turn instead). Once descending, the reporter didn't know why display became solid red, but he increased the descent rate until aircraft had descended more than 1200 ft and airspeed increased to vmo plus 20 to 25 KTS (370 to 375 KTS). At that time the aircraft probably went into protective overspd mode, but reporter says he was using full stick pressure to counteract any pitch up tendency from overspd protection. Reporter immediately told ATC that he was filing a near midair collision. As a result the regional FAA office contacted the reporter to check further. They had the tapes of the incident. When reporter reviewed the incident with his company training department, they told him that he didn't follow the correct procedures for the TCASII RA and he should have been using the digital descent read out.

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Original NASA ASRS Text

Title: NMAC. FLC CONFUSION FOLLOWING TCASII RA.

Narrative: DURING INITIAL CLB, TCASII GAVE US A TA AT 11:30 TO 12 O'CLOCK AND 2 MI, SAME ALT. OUT OF 11200 FT (APPROX) WE RECEIVED AN RA TO 'DSND.' ATC HAD ONLY 'UNVERIFIED' TFC AND APPARENTLY DID NOT HAVE TIME TO RESPOND TO OUR REQUEST FOR A VECTOR AWAY FROM THE TFC. TCASII THEN COMMANDED 'INCREASE DSCNT.' WE ATTEMPTED TO COMPLY WITH THE RA AND NEVER DID REACH THE GREEN AREA EVEN THOUGH WE WERE DOING MAX RATE OF DSCNT (5000 TO 8000 FPM DOWN). DURING THIS EVASIVE MANEUVER, WE EXCEEDED VMO BY 20 TO 25 KTS. UPON VISUALLY CONTACTING THE ALERT ACFT, IT WAS APPARENT TO BOTH THE FO AND MYSELF THAT THE PROPER MANEUVER WOULD HAVE BEEN TO CLB ABOVE THE TFC. WE NEVER DID HEAR 'CLR OF CONFLICT.' WE ALSO EXCEEDED 250 KIAS BELOW 10000 FT IN THIS EVASIVE MANEUVER. I THINK THE A320 TCASII DISPLAY IS FAULTY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR'S COMMENT, 'I THINK THE A320 TCASII DISPLAY IS FAULTY', IS BECAUSE THE RPTR BELIEVES THE RA COMMANDED EXCESSIVE DSCNT (5000 TO 8000 FPM) AND DURING THE MANEUVER THE ANALOG VERT SPD SCALE SHOWED SOLID RED. THEN, WHEN ACQUIRING THE INTRUDER ACFT VISUALLY, THE FLC'S CONSENSUS WAS THAT THE RA SHOULD HAVE COMMANDED A CLB INSTEAD OF DSCNT. RPTR'S ACFT WAS CLBING THROUGH 11200 FT AND LATER THE FAA TAPE REVIEW SHOWED THE INTRUDER TO BE A CESSNA 172 AT 11500 FT. THUS, THE COMMAND TO DSND WAS APPROPRIATE. HOWEVER, RPTR HAD JUST RECEIVED THE TFC ADVISORY FROM ATC, AND RPTR HAD REQUESTED A TURN. JUST AT THAT TIME THE RA COMMANDED 'INCREASE DSCNT' AND RPTR COMMENCED DSCNT (THE DSCNT COMMAND HAD ALREADY BEEN GIVEN, BUT RPTR PREFERRED TO TURN INSTEAD). ONCE DSNDING, THE RPTR DIDN'T KNOW WHY DISPLAY BECAME SOLID RED, BUT HE INCREASED THE DSCNT RATE UNTIL ACFT HAD DSNDED MORE THAN 1200 FT AND AIRSPD INCREASED TO VMO PLUS 20 TO 25 KTS (370 TO 375 KTS). AT THAT TIME THE ACFT PROBABLY WENT INTO PROTECTIVE OVERSPD MODE, BUT RPTR SAYS HE WAS USING FULL STICK PRESSURE TO COUNTERACT ANY PITCH UP TENDENCY FROM OVERSPD PROTECTION. RPTR IMMEDIATELY TOLD ATC THAT HE WAS FILING A NMAC. AS A RESULT THE REGIONAL FAA OFFICE CONTACTED THE RPTR TO CHK FURTHER. THEY HAD THE TAPES OF THE INCIDENT. WHEN RPTR REVIEWED THE INCIDENT WITH HIS COMPANY TRAINING DEPT, THEY TOLD HIM THAT HE DIDN'T FOLLOW THE CORRECT PROCS FOR THE TCASII RA AND HE SHOULD HAVE BEEN USING THE DIGITAL DSCNT READ OUT.

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.