As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING CLIMB AT FL150, THE LOW OIL PRESSURE WARNING ANNUNCIATED AND PRESSURE WAS OBSERVED TO DROP TO 35 PSIG. THE ENGINE WAS SHUTDOWN BY THE CREW WHEN THE PRESSURE REDUCED TO 20 PSIG AND THE AC RETURNED TO BASE. POST FLIGHT INVESTIGATION INDICATES THAT THE OIL FILLER CAP MAY NOT HAVE BEEN PROPERLY SECURED PRIOR TO THE FLIGHT. (TC NR 20080206013)