Narrative:

After lining up on runway 35, the tower changed our departure heading from 340 degrees to a 'left turn to 280 degrees, maintain 8000 ft MSL.' my copilot (PF) and I both set our HSI's to the new heading. After takeoff and approximately 800 ft AGL, the PF turned left to 280 degrees, continuing the climb to 8000 ft MSL. The initial climb rate was 2800 FPM at 200 KTS. I contacted salt lake departure, and a few seconds later, while 'mentally' flowing through the climb checklist, the PF suddenly initiated a moderate turn to the right and stated, 'he's coming right at us.' simultaneously, the radar controller called our traffic at ? Position and 9000 ft. At this time, I did not see the traffic nor did I have time to respond to the controller, but firmly commanded the PF 'to return to a 280 degree heading and to watch the climb rate!' the PF was apparently distracted by the traffic approaching from his 1 O'clock position and perceived it as a traffic conflict. I now saw the bright lights of the aircraft, hesitated briefly, and decided it was not a traffic conflict. The PF had now turned to an approximately heading of 300 degrees, when he started responding to my commands to turn back to the assigned heading. Now, as the assigned altitude of 8000 ft MSL was being reached, I emphatically called out 'altitude, altitude.' at approximately 8100 ft MSL, with palms of both hands, I briskly forced the control yoke forward arresting the climb near an altitude of 8300 ft MSL. The controller now entered the scenario requesting our heading and altitude. I quickly explained that the PF had 'perceived' a traffic conflict situation and had maneuvered the aircraft. The controller replied, 'that traffic was at 9000 ft MSL and your altitude may have been 8500 ft MSL, you may hear about this.' the entire incident lasted approximately 10 seconds.

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Original NASA ASRS Text

Title: A CPR FLC DEVIATED FROM ASSIGNED HEADING IN A MISTAKEN BELIEF THAT THEY WERE ON A COLLISION COURSE. WHILE RECOVERING FROM THE HEADING DEV THE FO CLBED ABOVE THE ASSIGNED ALT AND HAD A LTSS AND PERHAPS AN NMAC. THE CTLR SAID THAT THEY MAY HEAR ABOUT THIS.

Narrative: AFTER LINING UP ON RWY 35, THE TWR CHANGED OUR DEP HDG FROM 340 DEGS TO A 'L TURN TO 280 DEGS, MAINTAIN 8000 FT MSL.' MY COPLT (PF) AND I BOTH SET OUR HSI'S TO THE NEW HEADING. AFTER TKOF AND APPROX 800 FT AGL, THE PF TURNED L TO 280 DEGS, CONTINUING THE CLB TO 8000 FT MSL. THE INITIAL CLB RATE WAS 2800 FPM AT 200 KTS. I CONTACTED SALT LAKE DEP, AND A FEW SECONDS LATER, WHILE 'MENTALLY' FLOWING THROUGH THE CLB CHKLIST, THE PF SUDDENLY INITIATED A MODERATE TURN TO THE R AND STATED, 'HE'S COMING RIGHT AT US.' SIMULTANEOUSLY, THE RADAR CTLR CALLED OUR TFC AT ? POS AND 9000 FT. AT THIS TIME, I DID NOT SEE THE TFC NOR DID I HAVE TIME TO RESPOND TO THE CTLR, BUT FIRMLY COMMANDED THE PF 'TO RETURN TO A 280 DEG HDG AND TO WATCH THE CLB RATE!' THE PF WAS APPARENTLY DISTRACTED BY THE TFC APCHING FROM HIS 1 O'CLOCK POS AND PERCEIVED IT AS A TFC CONFLICT. I NOW SAW THE BRIGHT LIGHTS OF THE ACFT, HESITATED BRIEFLY, AND DECIDED IT WAS NOT A TFC CONFLICT. THE PF HAD NOW TURNED TO AN APPROX HDG OF 300 DEGS, WHEN HE STARTED RESPONDING TO MY COMMANDS TO TURN BACK TO THE ASSIGNED HEADING. NOW, AS THE ASSIGNED ALT OF 8000 FT MSL WAS BEING REACHED, I EMPHATICALLY CALLED OUT 'ALT, ALT.' AT APPROX 8100 FT MSL, WITH PALMS OF BOTH HANDS, I BRISKLY FORCED THE CTL YOKE FORWARD ARRESTING THE CLB NEAR AN ALT OF 8300 FT MSL. THE CTLR NOW ENTERED THE SCENARIO REQUESTING OUR HEADING AND ALT. I QUICKLY EXPLAINED THAT THE PF HAD 'PERCEIVED' A TFC CONFLICT SIT AND HAD MANEUVERED THE ACFT. THE CTLR REPLIED, 'THAT TFC WAS AT 9000 FT MSL AND YOUR ALT MAY HAVE BEEN 8500 FT MSL, YOU MAY HEAR ABOUT THIS.' THE ENTIRE INCIDENT LASTED APPROX 10 SECONDS.

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.