What was found
EN ROUTE FROM PHX TO ELP, DURING CRUISE, THE FIRST OFFICER'S SLIDING WINDOW ARCED AND CRACKED. FLIGHT RETURNED TO FIELD AT PHX AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED. MAINTENANCE REMOVED, REPLACED AND ADJUSTED THE FIRST OFFICER'S SLIDING WINDOW PER MM 56-12-11. OPERATIONAL CHECK GOOD.