Narrative:

It was the captain's leg and atlanta put us into a holding pattern. We were outbound from the fix at sinca at FL220. We were doing 20 mi legs when ATC called, 'air carrier X go ahead and start your right turn in toward sinca now for traffic.' the captain started slewing the heading bug around to drive the autoplt into a r-hand turn. I acknowledged ATC and started narrowing my focus on the TCASII display to see what traffic ATC was talking about. It looked like there was a guy ahead of us coming in the opposite direction, headed straight into the fix at sinca on the inbound holding course. He was about 12 mi away. If ATC hadn't had us turn at all, we would have passed about 5 mi or so abeam each other and then our normal turn at the end of the holding pattern would have probably put us in behind this other guy. But, as the airplane started to turn, I could tell that ATC's plan was for us to turn early and get in front of this guy for sequence. We were pretty slow, but still indicating around 240 KTS and our turn was causing the traffic to move from our 1 O'clock position to right on our nose. Suddenly, the white blip on my traffic scope turned yellow as we received a TA from our TCASII system. I was unable at that point to pick this traffic up visually. I believe I heard ATC clear somebody to FL230, 1000 ft above us, but I didn't know who they were talking to. A moment later, the blip turned red and we found ourselves fully involved in a TCASII RA. The captain disconnected the autoplt, but kept the turn in to keep increasing our lateral separation to the traffic while increasing power and raising the nose. Rolling wings level would have been correct as per our training, but had he done so it would have had the undesired effect of stopping our turn and with the outcome of an even greater loss of separation. I radioed to ATC that we're climbing in response to an RA while simultaneously rechking the TCASII screen and realizing that the target was now 300 ft above us. I realized that our target was the traffic that ATC had advised to climb. I directed the captain to ignore the TCASII and to descend immediately. The captain did so. Moments later, ATC replied they had already asked the other traffic to climb and now asked us to descend. Almost simultaneously, the TCASII began to command a descent. As the nose of our aircraft became level with the horizon and continued downward, we could finally see straight ahead. We passed the traffic with approximately 200 ft of vertical separation and 500 ft of lateral separation. Conclusion: although the ATC made the initial mistake in misjudging the turn radius required by our aircraft to turn inside the other traffic, either the ATC controller or both acfts' TCASII system could have resolved the conflict in a satisfactory manner. Unfortunately, they both wound up working at xpurposes, unable to anticipate the actions of the other, and made a bad situation even worse. Action by the crew in applying a common sense solution and continuing their turn and beginning a descent before the TCASII equipment caught its mistake, instead of using the prescribed maneuvers taught in training insured a successful outcome in this case. The captain's use of control in a timely yet gentle manner not only prevented a midair collision, but prevented injuries to passenger and flight attendants inside our aircraft. Recommendation: 1) once aircraft are inside a certain distance, ATC should anticipate an RA and realize that TCASII will resolve the conflict in a more timely and correct manner than the controller could. At that point the controller should limit his commands to those designed to increase lateral separation only. In our case, a well meaning controller made the situation worse by starting the other aircraft climbing at almost the exact same second that we received our RA to climb. 2) if we had 'tags' on our TCASII screens with aircraft call signs on them, then we would be able to know exactly to whom specific clrncs were given. In our case, this would have caused us to have greater situational awareness and we could have anticipated the RA and chosen to ignore it, knowing that it was erroneous and that the other aircraft had already been directed to climb. Less expensive collision avoidance system designed for GA (ryan) already have a feature allowing you to identify threat aircraft by side number. Modifying this feature to a programmable call sign, like we do with 'cpdlc,' should be possible and should be added to TCASII system for part 121 aircraft. 3) less expensive collision avoidance system designed for GA (garmin) already have a feature that predicts the directional path of threat aircraft for the next 30 seconds. Adding this to our TCASII would give us the ability to maneuver to maximize lateral separation while complying with a TA. Deviations of as little as 1 mi as a 'last ditch maneuver' would enhance safety while still keeping us within ATC navigation tolerances.

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Original NASA ASRS Text

Title: NMAC BTWN A HOLDING B777 AND AN INBOUND BIZJET AT FL220 NEAR THE SINCA INTXN ON FREQ WITH ZTL.

Narrative: IT WAS THE CAPT'S LEG AND ATLANTA PUT US INTO A HOLDING PATTERN. WE WERE OUTBOUND FROM THE FIX AT SINCA AT FL220. WE WERE DOING 20 MI LEGS WHEN ATC CALLED, 'ACR X GO AHEAD AND START YOUR R TURN IN TOWARD SINCA NOW FOR TFC.' THE CAPT STARTED SLEWING THE HDG BUG AROUND TO DRIVE THE AUTOPLT INTO A R-HAND TURN. I ACKNOWLEDGED ATC AND STARTED NARROWING MY FOCUS ON THE TCASII DISPLAY TO SEE WHAT TFC ATC WAS TALKING ABOUT. IT LOOKED LIKE THERE WAS A GUY AHEAD OF US COMING IN THE OPPOSITE DIRECTION, HEADED STRAIGHT INTO THE FIX AT SINCA ON THE INBOUND HOLDING COURSE. HE WAS ABOUT 12 MI AWAY. IF ATC HADN'T HAD US TURN AT ALL, WE WOULD HAVE PASSED ABOUT 5 MI OR SO ABEAM EACH OTHER AND THEN OUR NORMAL TURN AT THE END OF THE HOLDING PATTERN WOULD HAVE PROBABLY PUT US IN BEHIND THIS OTHER GUY. BUT, AS THE AIRPLANE STARTED TO TURN, I COULD TELL THAT ATC'S PLAN WAS FOR US TO TURN EARLY AND GET IN FRONT OF THIS GUY FOR SEQUENCE. WE WERE PRETTY SLOW, BUT STILL INDICATING AROUND 240 KTS AND OUR TURN WAS CAUSING THE TFC TO MOVE FROM OUR 1 O'CLOCK POS TO RIGHT ON OUR NOSE. SUDDENLY, THE WHITE BLIP ON MY TFC SCOPE TURNED YELLOW AS WE RECEIVED A TA FROM OUR TCASII SYS. I WAS UNABLE AT THAT POINT TO PICK THIS TFC UP VISUALLY. I BELIEVE I HEARD ATC CLR SOMEBODY TO FL230, 1000 FT ABOVE US, BUT I DIDN'T KNOW WHO THEY WERE TALKING TO. A MOMENT LATER, THE BLIP TURNED RED AND WE FOUND OURSELVES FULLY INVOLVED IN A TCASII RA. THE CAPT DISCONNECTED THE AUTOPLT, BUT KEPT THE TURN IN TO KEEP INCREASING OUR LATERAL SEPARATION TO THE TFC WHILE INCREASING PWR AND RAISING THE NOSE. ROLLING WINGS LEVEL WOULD HAVE BEEN CORRECT AS PER OUR TRAINING, BUT HAD HE DONE SO IT WOULD HAVE HAD THE UNDESIRED EFFECT OF STOPPING OUR TURN AND WITH THE OUTCOME OF AN EVEN GREATER LOSS OF SEPARATION. I RADIOED TO ATC THAT WE'RE CLBING IN RESPONSE TO AN RA WHILE SIMULTANEOUSLY RECHKING THE TCASII SCREEN AND REALIZING THAT THE TARGET WAS NOW 300 FT ABOVE US. I REALIZED THAT OUR TARGET WAS THE TFC THAT ATC HAD ADVISED TO CLB. I DIRECTED THE CAPT TO IGNORE THE TCASII AND TO DSND IMMEDIATELY. THE CAPT DID SO. MOMENTS LATER, ATC REPLIED THEY HAD ALREADY ASKED THE OTHER TFC TO CLB AND NOW ASKED US TO DSND. ALMOST SIMULTANEOUSLY, THE TCASII BEGAN TO COMMAND A DSCNT. AS THE NOSE OF OUR ACFT BECAME LEVEL WITH THE HORIZON AND CONTINUED DOWNWARD, WE COULD FINALLY SEE STRAIGHT AHEAD. WE PASSED THE TFC WITH APPROX 200 FT OF VERT SEPARATION AND 500 FT OF LATERAL SEPARATION. CONCLUSION: ALTHOUGH THE ATC MADE THE INITIAL MISTAKE IN MISJUDGING THE TURN RADIUS REQUIRED BY OUR ACFT TO TURN INSIDE THE OTHER TFC, EITHER THE ATC CTLR OR BOTH ACFTS' TCASII SYS COULD HAVE RESOLVED THE CONFLICT IN A SATISFACTORY MANNER. UNFORTUNATELY, THEY BOTH WOUND UP WORKING AT XPURPOSES, UNABLE TO ANTICIPATE THE ACTIONS OF THE OTHER, AND MADE A BAD SIT EVEN WORSE. ACTION BY THE CREW IN APPLYING A COMMON SENSE SOLUTION AND CONTINUING THEIR TURN AND BEGINNING A DSCNT BEFORE THE TCASII EQUIP CAUGHT ITS MISTAKE, INSTEAD OF USING THE PRESCRIBED MANEUVERS TAUGHT IN TRAINING INSURED A SUCCESSFUL OUTCOME IN THIS CASE. THE CAPT'S USE OF CTL IN A TIMELY YET GENTLE MANNER NOT ONLY PREVENTED A MIDAIR COLLISION, BUT PREVENTED INJURIES TO PAX AND FLT ATTENDANTS INSIDE OUR ACFT. RECOMMENDATION: 1) ONCE ACFT ARE INSIDE A CERTAIN DISTANCE, ATC SHOULD ANTICIPATE AN RA AND REALIZE THAT TCASII WILL RESOLVE THE CONFLICT IN A MORE TIMELY AND CORRECT MANNER THAN THE CTLR COULD. AT THAT POINT THE CTLR SHOULD LIMIT HIS COMMANDS TO THOSE DESIGNED TO INCREASE LATERAL SEPARATION ONLY. IN OUR CASE, A WELL MEANING CTLR MADE THE SIT WORSE BY STARTING THE OTHER ACFT CLBING AT ALMOST THE EXACT SAME SECOND THAT WE RECEIVED OUR RA TO CLB. 2) IF WE HAD 'TAGS' ON OUR TCASII SCREENS WITH ACFT CALL SIGNS ON THEM, THEN WE WOULD BE ABLE TO KNOW EXACTLY TO WHOM SPECIFIC CLRNCS WERE GIVEN. IN OUR CASE, THIS WOULD HAVE CAUSED US TO HAVE GREATER SITUATIONAL AWARENESS AND WE COULD HAVE ANTICIPATED THE RA AND CHOSEN TO IGNORE IT, KNOWING THAT IT WAS ERRONEOUS AND THAT THE OTHER ACFT HAD ALREADY BEEN DIRECTED TO CLB. LESS EXPENSIVE COLLISION AVOIDANCE SYS DESIGNED FOR GA (RYAN) ALREADY HAVE A FEATURE ALLOWING YOU TO IDENT THREAT ACFT BY SIDE NUMBER. MODIFYING THIS FEATURE TO A PROGRAMMABLE CALL SIGN, LIKE WE DO WITH 'CPDLC,' SHOULD BE POSSIBLE AND SHOULD BE ADDED TO TCASII SYS FOR PART 121 ACFT. 3) LESS EXPENSIVE COLLISION AVOIDANCE SYS DESIGNED FOR GA (GARMIN) ALREADY HAVE A FEATURE THAT PREDICTS THE DIRECTIONAL PATH OF THREAT ACFT FOR THE NEXT 30 SECONDS. ADDING THIS TO OUR TCASII WOULD GIVE US THE ABILITY TO MANEUVER TO MAXIMIZE LATERAL SEPARATION WHILE COMPLYING WITH A TA. DEVS OF AS LITTLE AS 1 MI AS A 'LAST DITCH MANEUVER' WOULD ENHANCE SAFETY WHILE STILL KEEPING US WITHIN ATC NAV TOLERANCES.

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.