What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) On 08/27/2003 at approximately 1435 EDT, nwaa flight 427, Boeing 757-200, N541US, reported a failure of the left hydraulic system. An emergency was declared. The aircraft landed without further incident. Maintenance personnel inspected the aircraft and found a failed o-ring in the left hydraulic system (red system) depressurization valve to be the cause. The o-ring was replaced along with other components which were damaged due to the loss of hydraulic fluid, I.e. pumps, filters, and the aircraft was returned to service.
As the FAA filed it
(-23) ON 08/27/2003 AT APPROXIMATELY 1435 EDT, NWAA FLIGHT 427, BOEING 757-200, N541US, REPORTED A FAILURE OF THE LEFT HYDRAULIC SYSTEM. AN EMERGENCY WAS DECLARED. THE AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE PERSONNEL INSPECTED THE AIRCRAFT AND FOUND A FAILED O-RING IN THE LEFT HYDRAULIC SYSTEM (RED SYSTEM) DEPRESSURIZATION VALVE TO BE THE CAUSE. THE O-RING WAS REPLACED ALONG WITH OTHER COMPONENTS WHICH WERE DAMAGED DUE TO THE LOSS OF HYDRAULIC FLUID, I.E. PUMPS, FILTERS, AND THE AIRCRAFT WAS RETURNED TO SERVICE.