Narrative:

Approaching adm I noticed a TCASII target ssw (proceeding northeast) of adm at FL350. I thought to myself this was why we had not received our descent clearance yet. As we passed adm and intercepted the outbound leg I noticed the TCASII target was now climbing and indicated a readout of FL360. At FL360 the trend arrow on the target began to fluctuate between up, down and neutral. The target was still about 10 plus mi away at our 12:30 - 1 O'clock position. The trend arrow then went up and stayed up with the altitude closure rate decreasing. I asked the first officer to inquire about the traffic. He did so and ATC indicated they had no traffic. I then directly asked ATC 'you show no traffic at our 1 O'clock position and 10 mi?' (the target had now closed to about 7 mi.) there was no response from ATC. The target was still closing so I initiated a 20 degree heading change to the right using the heading select mode on the autoplt. I told the first officer to inform ATC of our turn. About this time we got a TCASII alert and I increased both the amount of heading change and angle of bank (from 10 degrees to 30 degrees). By now the target was within 5 mi, still on an intercept heading and still climbing. The TCASII RA function went off and initially said 'descend.' I disconnected the autoplt and automatic throttles and commenced a descending right turn whereupon the TCASII changed its mind and told us to 'climb, climb now.' I started to climb (towards the RA command bars) but immediately became aware of a buffet. I pushed the nose over and rolled the airplane to approximately 40 degrees of bank. While all of this was occurring I was aware of ATC telling us to immediately turn to a heading of 280 degrees for traffic. I told ATC we were in a turn and descending for traffic avoidance. As we were turning I looked out my side window and saw what appeared to be a cpr Y jet in a hard right turn within 1 mi of our position. We rolled out on a 280 degree heading and leveled at FL350 putting us directly on a heading to reenter the WX we had just deviated around! We asked ATC if we could stay at FL350 whereupon the controller indicated 'negative, negative, climb to FL370.' I commenced a climb to FL370 and informed ATC we needed to turn left for WX avoidance.

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Original NASA ASRS Text

Title: ACR X TCASII RA HAD LTSS FROM CPR Y CLB TO SAME ALT. EVASIVE ACTION TAKEN. PLTDEV. SYS ERROR. TCASII LOGIC CHANGE IN RA INSTRUCTION.

Narrative: APCHING ADM I NOTICED A TCASII TARGET SSW (PROCEEDING NE) OF ADM AT FL350. I THOUGHT TO MYSELF THIS WAS WHY WE HAD NOT RECEIVED OUR DSCNT CLRNC YET. AS WE PASSED ADM AND INTERCEPTED THE OUTBOUND LEG I NOTICED THE TCASII TARGET WAS NOW CLBING AND INDICATED A READOUT OF FL360. AT FL360 THE TREND ARROW ON THE TARGET BEGAN TO FLUCTUATE BTWN UP, DOWN AND NEUTRAL. THE TARGET WAS STILL ABOUT 10 PLUS MI AWAY AT OUR 12:30 - 1 O'CLOCK POS. THE TREND ARROW THEN WENT UP AND STAYED UP WITH THE ALT CLOSURE RATE DECREASING. I ASKED THE FO TO INQUIRE ABOUT THE TFC. HE DID SO AND ATC INDICATED THEY HAD NO TFC. I THEN DIRECTLY ASKED ATC 'YOU SHOW NO TFC AT OUR 1 O'CLOCK POS AND 10 MI?' (THE TARGET HAD NOW CLOSED TO ABOUT 7 MI.) THERE WAS NO RESPONSE FROM ATC. THE TARGET WAS STILL CLOSING SO I INITIATED A 20 DEG HDG CHANGE TO THE R USING THE HDG SELECT MODE ON THE AUTOPLT. I TOLD THE FO TO INFORM ATC OF OUR TURN. ABOUT THIS TIME WE GOT A TCASII ALERT AND I INCREASED BOTH THE AMOUNT OF HDG CHANGE AND ANGLE OF BANK (FROM 10 DEGS TO 30 DEGS). BY NOW THE TARGET WAS WITHIN 5 MI, STILL ON AN INTERCEPT HDG AND STILL CLBING. THE TCASII RA FUNCTION WENT OFF AND INITIALLY SAID 'DSND.' I DISCONNECTED THE AUTOPLT AND AUTO THROTTLES AND COMMENCED A DSNDING R TURN WHEREUPON THE TCASII CHANGED ITS MIND AND TOLD US TO 'CLB, CLB NOW.' I STARTED TO CLB (TOWARDS THE RA COMMAND BARS) BUT IMMEDIATELY BECAME AWARE OF A BUFFET. I PUSHED THE NOSE OVER AND ROLLED THE AIRPLANE TO APPROX 40 DEGS OF BANK. WHILE ALL OF THIS WAS OCCURRING I WAS AWARE OF ATC TELLING US TO IMMEDIATELY TURN TO A HDG OF 280 DEGS FOR TFC. I TOLD ATC WE WERE IN A TURN AND DSNDING FOR TFC AVOIDANCE. AS WE WERE TURNING I LOOKED OUT MY SIDE WINDOW AND SAW WHAT APPEARED TO BE A CPR Y JET IN A HARD R TURN WITHIN 1 MI OF OUR POS. WE ROLLED OUT ON A 280 DEG HDG AND LEVELED AT FL350 PUTTING US DIRECTLY ON A HDG TO REENTER THE WX WE HAD JUST DEVIATED AROUND! WE ASKED ATC IF WE COULD STAY AT FL350 WHEREUPON THE CTLR INDICATED 'NEGATIVE, NEGATIVE, CLB TO FL370.' I COMMENCED A CLB TO FL370 AND INFORMED ATC WE NEEDED TO TURN L FOR WX AVOIDANCE.

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.