What was found
(CAN) IN CRUISE, ALT FAIL, IAS FAIL ON PFD #1. ASSOCIATED CAUTIONS FOR PITCH TRIM, ELEVATOR FEEL, PROP DEICE, SPOILER OB, ROLL SPLR OB HYD, RUD CNTRL. CB`S A7/A4 (LEFT UPPER) RELEASED. MAINTENANCE REPLACED THE #1 AIR DATA UNIT, COMPLETED THE OPS CHECKS AND THE AIRCRAFT WAS SUBSEQUENTLY RELEASED FOR SERVICE. (TC# 20190731017)