Narrative:

After departing slc runway 16R I was told to switch to departure frequency 135.5 and a right turn heading 280 degree. I contacted departure climbing through 6200 for 8000. The controller responded for me to maintain 8000, and I responded 'roger 8000.' approximately 30-45 seconds later the controller advised me of traffic, an medium large transport nebound at my 10 O'clock descending out of 11000 for 9000. I responded 'traffic northeast in sight.' in the process of looking for the traffic and scanning for additional traffic I scanned my panel and noticed the altimeter going through 8400. I immediately pushed the nose of the aircraft down and proceeded back to 8000 just as the controller advised me I was assigned 8000 and to descend immediately to 8000, traffic was descending to 9000. I responded 'roger, I have visual separation with the traffic,' and leveled at 8000. I was off my altitude for only a few seconds and no evasive action was necessary. I had the medium large transport in sight, but he was on a different frequency so I don't know if he saw me, was advised of my position or felt I was a hazard. I estimate the traffic passed above and behind my position by 1-2 mi. Before handing me off the controller asked me what my clearance had been and I responded '8000 ft.' I realized my mistake immediately and took prompt action to get back to my assigned altitude.

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Original NASA ASRS Text

Title: AIR TAXI CARGO FLT CLBS ABOVE ASSIGNED ALT. CONFLICT WITH MLG.

Narrative: AFTER DEPARTING SLC RWY 16R I WAS TOLD TO SWITCH TO DEP FREQ 135.5 AND A R TURN HDG 280 DEG. I CONTACTED DEP CLBING THROUGH 6200 FOR 8000. THE CTLR RESPONDED FOR ME TO MAINTAIN 8000, AND I RESPONDED 'ROGER 8000.' APPROX 30-45 SECONDS LATER THE CTLR ADVISED ME OF TFC, AN MLG NEBOUND AT MY 10 O'CLOCK DSNDING OUT OF 11000 FOR 9000. I RESPONDED 'TFC NE IN SIGHT.' IN THE PROCESS OF LOOKING FOR THE TFC AND SCANNING FOR ADDITIONAL TFC I SCANNED MY PANEL AND NOTICED THE ALTIMETER GOING THROUGH 8400. I IMMEDIATELY PUSHED THE NOSE OF THE ACFT DOWN AND PROCEEDED BACK TO 8000 JUST AS THE CTLR ADVISED ME I WAS ASSIGNED 8000 AND TO DSND IMMEDIATELY TO 8000, TFC WAS DSNDING TO 9000. I RESPONDED 'ROGER, I HAVE VISUAL SEPARATION WITH THE TFC,' AND LEVELED AT 8000. I WAS OFF MY ALT FOR ONLY A FEW SECONDS AND NO EVASIVE ACTION WAS NECESSARY. I HAD THE MLG IN SIGHT, BUT HE WAS ON A DIFFERENT FREQ SO I DON'T KNOW IF HE SAW ME, WAS ADVISED OF MY POS OR FELT I WAS A HAZARD. I ESTIMATE THE TFC PASSED ABOVE AND BEHIND MY POS BY 1-2 MI. BEFORE HANDING ME OFF THE CTLR ASKED ME WHAT MY CLRNC HAD BEEN AND I RESPONDED '8000 FT.' I REALIZED MY MISTAKE IMMEDIATELY AND TOOK PROMPT ACTION TO GET BACK TO MY ASSIGNED ALT.

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.