HDG DEV. TURNED TOO SOON ON SID. MISLEADING SID.

Narrative

EARLY TURN (APPROX 16 NM BEFORE ELMAA INTXN). DEP CTL COMMENTED THAT WE TURNED EARLY AND WERE THE SECOND ACFT THIS WK TO TURN EARLY. THE CTLR ALSO STATED THAT IT WAS NOT A PROB BUT WAS CURIOUS IF IT WAS OUR AUTOPLT LEADING THE TURN. CONTRIBUTING FACTORS ARE DISTANCE TO XCHK VOR; IT WAS CENTERING; INTERFERENCE OR JUST DISTANCE AND LOW ALT. THE VOR REF RADIAL CTRING COINCIDED WITH THE 32 DME/SEA. THE ACTUAL DME DISTANCE FROM SEA IS 48 NM; BUT THIS DOES NOT SHOW ON THE SID. THE 32 MI DISTANCE HAS NO RELEVANCE ON A VOR; DME; RADAR; SID; AND IT CAN BE MISLEADING IN A QUICK LOOK FOR A XCHK. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: DURING DEP ON THE ELMAA 4 DEP; DARK COCKPIT; BOTH PLTS HAD THE YYJ 157 DEG RADIAL SELECTED TO IDENT ELMAA AND THE TURN POINT. BOTH VOR ON COURSE BARS CENTERED AND WHEN THEY LOOKED AT THE DEP PAGE THEY SAW 32 ON THE SEA 227 DEG RADIAL WHICH WAS VERIFIED WITH THEIR DME'S; SO THEY STARTED THE TURN TO 330 DEG RADIAL TO UBG. DEP CTL CAUGHT THE ERROR AND NOTIFIED THE FLC; ALSO TELLING THEM THAT IT WAS THE THIRD TIME IN A WK THAT HE HAD SEEN THIS SAME PROB. RPTR SAYS THAT THE DEP IS NOT IN THE FMS AND THAT THE LAT/LONG DEPICTED ON THE PAE 185 DEG RADIAL IS MEANINGLESS TO FLCS. THEN; THE 32 MI BTWN THAT PAE 185 ON THE SEA 227 DEG IS MISLEADING. FIRST; IT IS NOT A DME AND THERE IS NOTHING TO REF THE 32 AND SECOND; IT MISLEADS PLTS TO THINK IT IS A DME BECAUSE IT IS THE ONLY MILEAGE SHOWN ON THE SEA 227 DEG RADIAL. BEING RESTR TO 5000 FT CONTRIBUTED TO THE FALSE ON COURSE SIGNAL. ELMAA; AT 95 DME FROM YYJ IS MARGINAL TO RECEIVE UNTIL AT HIGHER ALTS.