What was found
AIRCRAFT WILL NOT PRESSURIZE, CAB RATE 0 ALL THE WAY TO 13-13000 FEET, ^P 5.3 & 5.4, CABIN ALT WAS 0, ALSO AT 12000 FEET. OVERWEIGHT LANDING 47500 LBS SINK RATE WAS 200 FEET PER MIN, LANDING WAS SMOOTH NO BOUNCES. R & R DIGITAL CONTROLLER IAW AMM 21-31-01. OPERATIONS CHECKED GOOD, PARTS INTERCHANGEABLE IAW IPC. ACFT DESCEND RATE WITH LIMIT IAW AMM 05-50-25.