Narrative:

Our flight was dispatched with the FMC inoperative, which meant we had to navigation in manual VOR mode. I was hand-flying the aircraft.cleared to FL230 by ZLA on the SID from bur to sfo. At XX45Z, out of FL180 the captain went off frequency radio watch to make a passenger announcement. I was then instructed by ATC to 'slow to 250 KTS, proceed direct gmn VOR, contact ZLA on a new frequency.' I was leveling at FL230 and engaged the autoplt and using the MCP. Reset speed to 250 KTS. The autothrottles were engaged and were retarding to idle to slow down from 300 KTS to 250 KTS. The captain not in the loop reached up and reengaged VNAV mode which immediately advanced the speed and throttles back toward 300 KTS. I instructed him that we are to slow to 250 KTS, and I reselected 250 KTS on the MCP and told him to make the check-in call on the new frequency. Somewhere during this point he set FL250 in the altitude select window. He reselected VNAV which caused the aircraft to climb. He contacted ATC leveling FL250. ATC said to go back to old frequency. Upon reestablishing contact, ATC questioned our altitude. ATC said to 'turn right heading 310 degrees, traffic 12 O'clock, less than 5 mi or so.' ATC said we were never cleared to FL250, only FL240. Once clear of traffic, ATC cleared us on course and climb to FL310. I believe a possible conflict alert happened. The captain was not in the loop and not following SOP's by selecting pitch modes on the MCP. I suggested he not make anymore changes or passenger announcements while not at cruise. Neither of us remember being cleared to FL250, but he assumed it by insistence on 250 KTS might have confused him and lead him to put FL250 in the altitude window. Supplemental information from acn 167713: captain put too much load on the first officer to listen to ATC while he was hand-flying. Attention was diverted by captain, although listening by talking to passenger. First officer did not question when the altitude was changed to 25000'.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION WHEN ACFT CLIMBED TO FL250 VERSUS CLEARED 250 KTS.

Narrative: OUR FLT WAS DISPATCHED WITH THE FMC INOP, WHICH MEANT WE HAD TO NAV IN MANUAL VOR MODE. I WAS HAND-FLYING THE ACFT.CLRED TO FL230 BY ZLA ON THE SID FROM BUR TO SFO. AT XX45Z, OUT OF FL180 THE CAPT WENT OFF FREQ RADIO WATCH TO MAKE A PAX ANNOUNCEMENT. I WAS THEN INSTRUCTED BY ATC TO 'SLOW TO 250 KTS, PROCEED DIRECT GMN VOR, CONTACT ZLA ON A NEW FREQ.' I WAS LEVELING AT FL230 AND ENGAGED THE AUTOPLT AND USING THE MCP. RESET SPD TO 250 KTS. THE AUTOTHROTTLES WERE ENGAGED AND WERE RETARDING TO IDLE TO SLOW DOWN FROM 300 KTS TO 250 KTS. THE CAPT NOT IN THE LOOP REACHED UP AND REENGAGED VNAV MODE WHICH IMMEDIATELY ADVANCED THE SPD AND THROTTLES BACK TOWARD 300 KTS. I INSTRUCTED HIM THAT WE ARE TO SLOW TO 250 KTS, AND I RESELECTED 250 KTS ON THE MCP AND TOLD HIM TO MAKE THE CHK-IN CALL ON THE NEW FREQ. SOMEWHERE DURING THIS POINT HE SET FL250 IN THE ALT SELECT WINDOW. HE RESELECTED VNAV WHICH CAUSED THE ACFT TO CLB. HE CONTACTED ATC LEVELING FL250. ATC SAID TO GO BACK TO OLD FREQ. UPON REESTABLISHING CONTACT, ATC QUESTIONED OUR ALT. ATC SAID TO 'TURN RIGHT HDG 310 DEGS, TFC 12 O'CLOCK, LESS THAN 5 MI OR SO.' ATC SAID WE WERE NEVER CLRED TO FL250, ONLY FL240. ONCE CLR OF TFC, ATC CLRED US ON COURSE AND CLB TO FL310. I BELIEVE A POSSIBLE CONFLICT ALERT HAPPENED. THE CAPT WAS NOT IN THE LOOP AND NOT FOLLOWING SOP'S BY SELECTING PITCH MODES ON THE MCP. I SUGGESTED HE NOT MAKE ANYMORE CHANGES OR PAX ANNOUNCEMENTS WHILE NOT AT CRUISE. NEITHER OF US REMEMBER BEING CLRED TO FL250, BUT HE ASSUMED IT BY INSISTENCE ON 250 KTS MIGHT HAVE CONFUSED HIM AND LEAD HIM TO PUT FL250 IN THE ALT WINDOW. SUPPLEMENTAL INFO FROM ACN 167713: CAPT PUT TOO MUCH LOAD ON THE F/O TO LISTEN TO ATC WHILE HE WAS HAND-FLYING. ATTN WAS DIVERTED BY CAPT, ALTHOUGH LISTENING BY TALKING TO PAX. F/O DID NOT QUESTION WHEN THE ALT WAS CHANGED TO 25000'.

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.