As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PIT - FL 441 - AFTER TAKEOFF FROM PIT AND REACHING 6000 FEET, CREW COULD NOT PRESSURIZE THE AIRCRAFT. FLIGHT RETURNED TO PIT AND LANDED WITH NO FURTHER INCIDENT. MAINTENANCE FOUND A CRIMPED SENSE LINE TO THE PRESSURE CONTROLLER. LINE WAS REPLACED AND REPOSITIONED SO AS NOT TO CAUSE A CRIMPING CONDITION. (M)