What was found
SIGNIFICANT TAIL OSCILLATION FLT LVL 310 280KTS AT BEGINNING OF DESCENT. WENT AWAY WITH SLOWER SPEED. SPOKE WITH CAPTAIN AND HE STATED WAS A TAIL WAGGING NO SHUDDERING. NO ROLL OR PITCH PROBLEM LASTED 10-15 SECONDS. REPLACED RT ELEVATOR SERVO 34CE2 DUE TO OSCILLATION. ACCOMPLISHED ADJUSTMENT AND RIG CHECK ELEVATOR SYS & SOLD TO INSPECTION. ALL 4 AILERONS PCA'S SIMULTANEOUSLY HAS FAILED "BOX, DETECTION UNIT, LVDT" PHYSICALLY CRACKED -THROUGH AT ONE EACH MOUNT POINTS OF EACH PCA. INSTALLED -85 AT RT INBD, -168 AT LT OTBD AND -101 AT LT INBD. ONE MORE SERVO ON ORDER. STILL NEED LEAK AND OPS CHECK. REPLACED THE GREEN SYS YAW DAMPER AND NR1 FAC COMPUTER ON WUP M7502Q.