B727-200 ON MADWIN 3 STAR OAK IS PUT ON VECTOR AND DSCNT SLOW TO 160 KTS ON 260 DEG HDG; MAINTAIN 3200 FT. REDUCED DSCNT RATE TO 700 FPM. AT 3500 FT; GPWS SOUNDED. IMMEDIATE CLB WAS INITIATED AND WARNING STOPPED AT 4000 FT. WAS EXPECTING TO INTERCEPT THE GS ABOVE. FLC HAD PREPARED FOR CAT III APCH. CTLR ASSURED FLC 3200 FT WAS THE MVA IN THEIR AREA.

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I WAS PF ON RADAR VECTORS TO AN ILS RWY 29 AT OAK. DURING RADAR VECTORED DSCNT OFF MADWIN 3 ARR FROM 7000 FT; FLT WAS INSTRUCTED TO SLOW TO 180 KTS; THEN 160 KTS WITH SEVERAL HDG CHANGES TOWARD THE ARPT AND WITH CLRNC TO INTERCEPT THE LOC. WHILE INSTRUCTED TO SLOW TO 160 KTS A HDG ISSUED WAS 260 DEGS (LOC IS 294 DEGS) AND ALT ASSIGNED 3200 FT MSL. LOC FREQ WAS TUNED AND IDENTED ON BOTH SIDES WITH FLT DIRECTOR IN HDG MODE BUT ARMED FOR LOC CAPTURE. AS THE ACFT PASSED BELOW 4000 FT; I APPLIED THRUST AND REDUCED DSCNT RATE TO APPROX 700 FPM. AT 3500 FT; THE GPWS SOUNDED A SINGLE 'TERRAIN' ALERT; FOLLOWED BY A 'PULL UP' WARNING. THE FO RADAR ALTIMETER INDICATED 1600-1800 FT ABSOLUTE. THE CAPT AND I AGGRESSIVELY INITIATED AN ESCAPE MANEUVER. ALL ALERTS CLRED AT APPROX 4000 FT MSL. ATC WAS ADVISED OF OUR EVENT; AND WE WERE ASSURED THAT 3200 FT WAS THE CORRECT MVA. ASIDE FROM POSSIBLE OUT OF TOLERANCE EQUIP; I BELIEVE THE ACFT WAS NW OF WHERE THE CTLR EXPECTED THE FLT TO TRACK FROM HIS HDGS DUE TO A SOUTHERLY WIND FACTOR (SURFACE RPT 180/08). RAW DATA GS INDICATIONS LED ME TO EXPECT LOC CAPTURE ABOVE GS. IT SHOULD BE NOTED THAT THIS ACFT AND CREW WERE IN CAT 3A STATUS. ATC MIGHT WISH TO RECONSIDER THEIR MVA SECTORS VS GPWS THRESHOLDS AND TFC FLOWS/SPACING POLICY.