Narrative:

On climb out of slc in VNAV and direct abq in LNAV, autoplt on. We visually spotted traffic given crossing right to left. First officer directed his attention to the aircraft manuals trying to resolve a reverser light. I watched the crossing traffic for a period to determine the closure bearing. Seeing that we were going to pass behind him stated that to the first officer. As the reported traffic converged we received a frequency change from 134.8 to 132.55. The first officer put his manuals aside and dialed 132.55 on #1 radio. He experienced a problem with the tuning (all #'south wanted to rotate with the lower knob, which he demonstrated to me). He then switched to the other side of the radio head and made a call to center. No answer. Meanwhile, I was watching the closure of the aircraft passing and not wanting to fly through his wake, I stopped the climb, glancing at the MCP altitude window to check our restriction. We had 36000' showing. I started to ask the previous center frequency. The center directed us to descend to FL310. I looked to see what altitude I had stopped the climb and saw fl 318. Shortly after we were asked to verify that our altitude limit was FL310 and I said that I could not because we showed a higher altitude in our window. We were of course concerned how the FL360 got in the MCP window. Noting that each of our attention was diverted momentarily, it is my belief that it changed itself and we did not change it. It is not an altitude that we would select and we did not knowingly select it.

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Original NASA ASRS Text

Title: ACR MLG OVERSHOT ALT IN CLIMB CAUSING LESS THAN STANDARD SEPARATION.

Narrative: ON CLBOUT OF SLC IN VNAV AND DIRECT ABQ IN LNAV, AUTOPLT ON. WE VISUALLY SPOTTED TFC GIVEN XING RIGHT TO LEFT. F/O DIRECTED HIS ATTN TO THE ACFT MANUALS TRYING TO RESOLVE A REVERSER LIGHT. I WATCHED THE XING TFC FOR A PERIOD TO DETERMINE THE CLOSURE BEARING. SEEING THAT WE WERE GOING TO PASS BEHIND HIM STATED THAT TO THE F/O. AS THE RPTED TFC CONVERGED WE RECEIVED A FREQ CHANGE FROM 134.8 TO 132.55. THE F/O PUT HIS MANUALS ASIDE AND DIALED 132.55 ON #1 RADIO. HE EXPERIENCED A PROB WITH THE TUNING (ALL #'S WANTED TO ROTATE WITH THE LOWER KNOB, WHICH HE DEMONSTRATED TO ME). HE THEN SWITCHED TO THE OTHER SIDE OF THE RADIO HEAD AND MADE A CALL TO CENTER. NO ANSWER. MEANWHILE, I WAS WATCHING THE CLOSURE OF THE ACFT PASSING AND NOT WANTING TO FLY THROUGH HIS WAKE, I STOPPED THE CLB, GLANCING AT THE MCP ALT WINDOW TO CHK OUR RESTRICTION. WE HAD 36000' SHOWING. I STARTED TO ASK THE PREVIOUS CENTER FREQ. THE CENTER DIRECTED US TO DSND TO FL310. I LOOKED TO SEE WHAT ALT I HAD STOPPED THE CLB AND SAW FL 318. SHORTLY AFTER WE WERE ASKED TO VERIFY THAT OUR ALT LIMIT WAS FL310 AND I SAID THAT I COULD NOT BECAUSE WE SHOWED A HIGHER ALT IN OUR WINDOW. WE WERE OF COURSE CONCERNED HOW THE FL360 GOT IN THE MCP WINDOW. NOTING THAT EACH OF OUR ATTN WAS DIVERTED MOMENTARILY, IT IS MY BELIEF THAT IT CHANGED ITSELF AND WE DID NOT CHANGE IT. IT IS NOT AN ALT THAT WE WOULD SELECT AND WE DID NOT KNOWINGLY SELECT IT.

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.