MLG CAPT MISREAD STAR ON ARR AT PIE.

Narrative

FLYING DADES TWO ARR FOR TAMPA INTL; RWY 18L/R IN USE. APCH INFORMED CREW TO EXPECT APCH (VISUAL) TO RWY 18L. IT WAS THE CAPT'S LEG AND AS HE WAS TRACKING THE PIE 039 DEG RADIAL AS DEPICTED ON THE ARR I; PUT ASIDE MY DADES TWO ARR REPLACING IT WITH THE ILS RWY 18L APCH CHART. SHORTLY THEREAFTER THE CAPT ASKED IF ATC HAD GIVEN US A HEADING YET AND I REPLIED THEY HAD NOT. HE THEN TURNED TO A 180 DEG HDG AND HAD NO SOONER STOPPED THE TURN WHEN ATC ASKED OUR HEADING AND WHEN TOLD ISSUED AN IMMEDIATE TURN TO 270 DEGS. THE REST OF THE APCH AND LNDG PROCEEDED NORMALLY AND UNEVENTFULLY. CAUSE: THE CAPT MISINTERPRETED THE ARR DEPICTION ASSUMING THAT THE 180 DEG HDG WAS FOR RWY 18 LNDGS; HOWEVER THE ACCOMPANYING TEXT STATED THE 180 DEG HDG IS FOR RWY 36 LNDGS. CONTRIBUTING FACTORS: MY ASSUMING THAT SINCE THE CAPT WAS PROPERLY FLYING THE ARR HE WOULD CONTINUE TO DO SO. AS I STATED BEFORE I REPLACED MY ARR CHART WITH THE ILS APCH CHART AND HAD NO IDEA THE CAPT WAS FLYING THE ARR INCORRECTLY. IT WON'T HAPPEN AGAIN. ALSO IT DID TAKE SEVERAL MOMENTS OF LOOKING AT THE CHART AFTERWARDS TO FIGURE OUT WHAT UPSET ATC. THE CHART IS IN FACT SLIGHTLY CONFUSING.