What was found
DURING CLIMBOUT, KIAS 225 A/C EXPERIENCE AIRFRAME VIB. ADVISED CCIA FLT FOLLOWING & ATC OF PROBLEM & AIR TURNBACK. NO EMERGENCY ACTION TAKEN & A/C LANDED W/O INCIDENT. A/C INSPECTED & FOUND INBRD FLAPS ECCENTRICS NUT MISSING. REPLACED & ADJUST ECCENTRICS PER B727 MM. INSPECTED ALL FLT SURFACES, NO DEFECTS NOTED. A/C RETURNED TO SERVICE. DURING CLIMB, KIAS 225 NOTED AIRFRAME VIB MORE THAN PREVIOUS FLT. INFORMED CCIA FLT FOLLOWING, NOTIFIED ATC & A/C DIVERTED & LANDED W/O INCIDENT. A/C INSPECTED PER B727 MM INFLT VIBRATION TROUBLESHOOTING & FOUND A WEAK TENSION SPRING ON RT INBRD AFT FLAP. REPLACED TENSION SPRING IAW MM. LAF ACCOMPLISHED SATISFACTORY, NO VIB NOTED. A/C RETURNED TO SERVICE. (K)