What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Just prior to descent, hydraulic system 2 lo quantity eicas message appeared. Shortly after, hydraulic 2 lo pressure appeared. Crew declared emergency with ATC, performed checklists. Landed without incident and was towed from taxiway to the gate. Hydraulic fluid was noted under the #2 engine.
Maintenance found source of hydraulic leak to be #2 engine hydraulic pressure line bulkhead fitting and b-nut. Maintenance removed and replaced pressure line and noted no futher leaks and ops check good. Incident was reported due to the failure of #2 hydraulic system left a single hydraulic system, #3, powering ailerons and elevators.
As the FAA filed it
JUST PRIOR TO DESCENT, HYDRAULIC SYSTEM 2 LO QUANTITY EICAS MESSAGE APPEARED. SHORTLY AFTER, HYDRAULIC 2 LO PRESSURE APPEARED. CREW DECLARED EMERGENCY WITH ATC, PERFORMED CHECKLISTS. LANDED WITHOUT INCIDENT AND WAS TOWED FROM TAXIWAY TO THE GATE. HYDRAULIC FLUID WAS NOTED UNDER THE #2 ENGINE.
MAINTENANCE FOUND SOURCE OF HYDRAULIC LEAK TO BE #2 ENGINE HYDRAULIC PRESSURE LINE BULKHEAD FITTING AND B-NUT. MAINTENANCE REMOVED AND REPLACED PRESSURE LINE AND NOTED NO FUTHER LEAKS AND OPS CHECK GOOD. INCIDENT WAS REPORTED DUE TO THE FAILURE OF #2 HYDRAULIC SYSTEM LEFT A SINGLE HYDRAULIC SYSTEM, #3, POWERING AILERONS AND ELEVATORS.