MLG CLBED PAST FL350 TO FL357.

Narrative

WE WERE CLRED BY ZOA FL350. I DO NOT REMEMBER WHO SET THE ALT WINDOW ON THE FLT CTL PANEL. I THINK I DID; BUT THE CAPT (THE PF) IS SOMEWHAT NONSTANDARD AND WOULD OFTEN SET ALTS WHEN HE WAS FLYING; EVEN THOUGH THIS IS NOT SOP. PASSING FL200 THE CAPT GOT OUT OF HIS SEAT TO GO TO THE BATHROOM. I BUSIED MYSELF ENTERING THE WINDS INTO THE FMS. THE FMS PROGRAM WAS DIFFERENT THAN MOST; FOR THIS TYPE OF ACFT; SO IT TOOK ME A BIT LONGER THAN USUAL. ZOA CALLED AND INFORMED ME THAT THERE WOULD BE A 10 MIN DELAY FOR FL370; OUR CRUISE ALT. I CHKED ALT PASSING FL340 AND NOTED ALT CAPTURE WAS NOT INDICATED ON THE FMA. AS THE ACFT APCHED FL350 I LOOKED AROUND THE COCKPIT FOR THE REASON THE ACFT WAS NOT LEVELING. I THEN NOTICED THE ALT WINDOW ON FLT CTL PANEL READ FL380. I QUICKLY SET FL350. THE ACFT DID NOT LEVEL OFF DUE TO FLT DIRECTOR LOGIC AND CONTINUED TO CLB TO FL370; THE ALT IN THE FMS AS THE CRUISE ALT. I SELECTED LEVEL CHANGE ON THE FLT DIRECTOR MODE SELECTOR. THE ACFT FINALLY LEVELED OFF AT FL350; BUT DID CLB TO FL357. ZOA ASKED THE ALT. I TOLD ZOA FL350. ZOA STATED 'I SHOW YOU AT FL357.' I SAID 'WE WOULD CHK ON IT.' I DID NOT TURN OFF THE AUTOPLT BECAUSE I WANTED TO MAKE A SMOOTH LEVELOFF. I DID NOT THINK IT WOULD TAKE THE ACFT 1000-700 FT TO LEVEL OFF AND THEN START A DSCNT IN THE LEVEL CHANGE MODE. I AM NOT SURE HOW FL380 GOT IN THE ALT WINDOW. THE CAPT IS 2 MONTHS FROM RETIREMENT. I THINK HE COULD HAVE TURNED THE ALT KNOB INSTEAD OF THE HDG KNOB THEN RESET IT TO FL380 WHILE I WAS NOT LOOKING.