DC10 FO DID NOT FLY HDG 340 DEGS AS STIPULATED ON THE SID.

Narrative

RECEIVED A PDC THAT WAS AMBIGUOUS. THE ROUTING THAT WAS GIVEN COULD HAVE TAKEN US INTO THE MOUNTAINS E OF SALT LAKE CITY. WE WERE GIVEN THE SALT LAKE 8 (TCH8.TCH) DEP; MAINTAIN 10000 FT. THE RTE OF FLT WAS AS FILED EXCEPT '-- TCH 094; MTU 303; MTU. DBL --' IT COULD BE INTERPRETED THAT; WHEN XING TCA VOR; PROCEED OUTBOUND ON THE 094 DEG RADIAL TO INTERCEPT THE MTU 303 DEG RADIAL INBOUND TO MTU VOR; THEN DIRECT DBL VOR. WHAT WOULD HAVE BEEN BETTER WOULD BE -- VECTORS TO 'TCH 094; MTU 303.MTU.DBL --' SO; IT WOULD BE VERY CLR THAT DEP CTL WOULD VECTOR US TO THE TCH 094 WHEN THEY WANTED US THERE. AS IT WAS; THE FO STARTED HIS TURN AT THE VOR TO INTERCEPT THE 094 DEG RADIAL; AND WAS THROUGH APPROX 30 DEG TURN BEFORE THE ERROR WAS CAUGHT. WE WERE STILL WITHIN A MI OF THE VOR WHEN I TOOK CTL OF THE AIRPLANE AND TURNED BACK TO THE HDG ON THE SID. SUPPLEMENTAL INFO FROM ACN 579376: WE EXPECTED; AND RECEIVED; TKOF CLRNC ON RWY 34R; WHICH STATES 'FLY 340 DEG HDG OR AS ASSIGNED.' LATER THE PROC SAYS TO EXPECT VECTORS TO ASSIGNED RTE OR FIX. I THOUGHT THE INTENTION WAS FOR US TO FLY 340 DEG HDG UNTIL REACHING TCH; THEN TURN R TO INTERCEPT THE TCH 094 DEG RADIAL; ABOUT 2 MINS AFTER TKOF ROLL BEGAN. SLC DEP CALLED US AFTER I TURNED 30-40 DEGS AND TOLD US TO MAKE AN IMMEDIATE R TURN TO 330 DEGS. I MISSED THIS FIRST CALL; BUT HEARD IT REPEATED AS THE CAPT TOOK THE AIRPLANE AND MADE THE TURN L AS DIRECTED. I FOUND THE PRE-DEP CLRNC MISLEADING AS PRINTED. THIS WAS MY FIRST TIME INTO SLC; AND THE CAPT'S SECOND. IT WAS THE FIRST TIME EITHER OF US TOOK OFF TO THE N THERE.