Narrative:

On the clearance for takeoff, tower told our flight to turn right 330 degrees and maintain 3000'. All was complied with and told to contact departure. Upon tuning in with departure, major airline (X) was somewhat interrogating departure control as to why he wanted them back down to 3000'. We squeezed in our 3000' initial contact with departure with a roger reply. Throughout the conversation between major X and departure I watched the major as they paralleled us going 330 degrees. Then departure told major to turn right heading 090 degrees and to please go back to 3000'. Major X complied still 'barking' about the idea of staying at 3000'. As I watched the major descend and turn right heading 090 degrees, I told departure that I would have to deviate. Departure came back and said, 'don't deviate to the west,' then paused and asked if our transponder was on. I did not reply, just switched to #1 transponder immediately and climbed 200' above assigned altitude and watched the major X go underneath our flight. After a pause, departure gave me a 360 degree heading and an 090 degree heading to fly the SID. It turned out that our #2 transponder was intermittent and by the time I switched to #1 probably no C/a went off in the departure control room. I also believe that the major X never saw us. Nothing more was ever said as we both contacted center.

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Original NASA ASRS Text

Title: ATX LTT FAILS TO ACTIVATE TRANSPONDER PRIOR TO TKOF. DEP CTLR VECTORS ACFT ACROSS PATH OF TKOF FROM PARALLEL RWY RESULTING IN NMAC. OPERATIONAL ERROR.

Narrative: ON THE CLRNC FOR TKOF, TWR TOLD OUR FLT TO TURN RIGHT 330 DEGS AND MAINTAIN 3000'. ALL WAS COMPLIED WITH AND TOLD TO CONTACT DEP. UPON TUNING IN WITH DEP, MAJOR AIRLINE (X) WAS SOMEWHAT INTERROGATING DEP CTL AS TO WHY HE WANTED THEM BACK DOWN TO 3000'. WE SQUEEZED IN OUR 3000' INITIAL CONTACT WITH DEP WITH A ROGER REPLY. THROUGHOUT THE CONVERSATION BTWN MAJOR X AND DEP I WATCHED THE MAJOR AS THEY PARALLELED US GOING 330 DEGS. THEN DEP TOLD MAJOR TO TURN RIGHT HDG 090 DEGS AND TO PLEASE GO BACK TO 3000'. MAJOR X COMPLIED STILL 'BARKING' ABOUT THE IDEA OF STAYING AT 3000'. AS I WATCHED THE MAJOR DSND AND TURN RIGHT HDG 090 DEGS, I TOLD DEP THAT I WOULD HAVE TO DEVIATE. DEP CAME BACK AND SAID, 'DON'T DEVIATE TO THE W,' THEN PAUSED AND ASKED IF OUR XPONDER WAS ON. I DID NOT REPLY, JUST SWITCHED TO #1 XPONDER IMMEDIATELY AND CLBED 200' ABOVE ASSIGNED ALT AND WATCHED THE MAJOR X GO UNDERNEATH OUR FLT. AFTER A PAUSE, DEP GAVE ME A 360 DEG HDG AND AN 090 DEG HDG TO FLY THE SID. IT TURNED OUT THAT OUR #2 XPONDER WAS INTERMITTENT AND BY THE TIME I SWITCHED TO #1 PROBABLY NO C/A WENT OFF IN THE DEP CTL ROOM. I ALSO BELIEVE THAT THE MAJOR X NEVER SAW US. NOTHING MORE WAS EVER SAID AS WE BOTH CONTACTED CENTER.

Data retrieved from NASA's ASRS site as of August 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.