As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ALL 3 (CAPT'S, FO'S & ALTERANTE) AIRSPEED INDICATIONS ARE UNRELIABLE. AIR TURN BACK - EMERGENCY DECLARED. REPLACED STANDBY ALT/AIRSPEED INDICATOR PER MM 34-11-02-4. R&R AUXILIARY PITOT STATIC DRAIN. SYSTEM OPS CKS NORMAL IAW AMM 34-12-00-5.