Narrative:

Very short taxi to departure arwy. Failed to set transponder code in transponder. Clearance/ground had cleared us via SID, which requires runway heading. Called tower for departure. 'Cleared to take off left turn 250 degrees,' on runway 20. We were waiting for takeoff on 2. Asked tower to repeat. 'Cleared for takeoff runway 2, left 250 degrees.' trained to think. We knew he didn't want 250 degrees. Just as we broke ground with first officer flying, I noticed incorrect code in transponder and attempted change. Turned wrong knob to off. First officer knew we didn't need to turn. Went runway heading as required for SID for that runway. Tower told us to start turn to left, 'traffic at 10 O'clock, 2000', your altitude!' we didn't turn west/O a visibility on the traffic. Picked traffic up visually. Tight turn behind and above traffic. Combination of factors, 'knew' what he wanted being the biggest. If the controller would have said, 'cleared departure runway 2, tight left turn for traffic,' problem/chance for misunderstanding/error would have been eliminated.

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Original NASA ASRS Text

Title: CPR LTT TRACK HEADING DEVIATION RESULTS IN CLOSE PROX WITH OPPOSITE DIRECTION TRAFFIC. FLT CREW FAILED TO COMPLY WITH CLRNC AS GIVEN.

Narrative: VERY SHORT TAXI TO DEP ARWY. FAILED TO SET XPONDER CODE IN XPONDER. CLRNC/GND HAD CLRED US VIA SID, WHICH REQUIRES RWY HDG. CALLED TWR FOR DEP. 'CLRED TO TAKE OFF LEFT TURN 250 DEGS,' ON RWY 20. WE WERE WAITING FOR TKOF ON 2. ASKED TWR TO REPEAT. 'CLRED FOR TKOF RWY 2, LEFT 250 DEGS.' TRAINED TO THINK. WE KNEW HE DIDN'T WANT 250 DEGS. JUST AS WE BROKE GND WITH F/O FLYING, I NOTICED INCORRECT CODE IN XPONDER AND ATTEMPTED CHANGE. TURNED WRONG KNOB TO OFF. F/O KNEW WE DIDN'T NEED TO TURN. WENT RWY HDG AS REQUIRED FOR SID FOR THAT RWY. TWR TOLD US TO START TURN TO LEFT, 'TFC AT 10 O'CLOCK, 2000', YOUR ALT!' WE DIDN'T TURN W/O A VIS ON THE TFC. PICKED TFC UP VISUALLY. TIGHT TURN BEHIND AND ABOVE TFC. COMBINATION OF FACTORS, 'KNEW' WHAT HE WANTED BEING THE BIGGEST. IF THE CTLR WOULD HAVE SAID, 'CLRED DEP RWY 2, TIGHT LEFT TURN FOR TFC,' PROB/CHANCE FOR MISUNDERSTANDING/ERROR WOULD HAVE BEEN ELIMINATED.

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.