As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MIA - FLT 1901 - EN ROUTE MAI-SDQ - LEFT CAPTAINS AIRSPEED ABOUT 50 KNOTS SLOW AT 250 KNOTS. 20 KNOTS SLOW AT 150 KNOTS. RETURNED AND LANDED MIA WITHOUT INCIDENT. REPLACED NR 1 AIR DATA COMPUTER. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)