As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: DCA-ALB DIVERTED TO PHL ACCOUNT OF MAINTENANCE, NO.1 ENGINE COMPRESSION STALL INDICATION. AN EMERGENCY WAS DECLARED, AND THE AIRCRAFT WAS NOT OVERWEIGHT FOR LANDING. THE FLIGHT LANDED WITHOUT INCIDENT AND TAXIED TO THE GATE UNDER ITS OWN POWER. MAINTENANCE . FOUND BAD IP CHECK VALVE ON ENG 1. REPLACED IP CHECK VALVE . OPS/LEAK CHECK NORMAL. REF: AMM 36-11-41. SEE 10194 FOR INDIVIDUAL SIGN OFFS.