What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
While in cruise enroute from yyz to chs, crew encountered a hyd 2 lo qty eicas message. At that time qty was at 22%. Within five minutes hyd 2 lo pressure and the quantity was at 0%.
ATC was advised that the flight needed to return to yyz due to weather concerns in chs. Crew carried out hyd 2 lo pressure qrh checklist and loss of hydraulic system 2. The aircraft was over max landing weight by about 630KGS initially, and crew advised ATC they would require a hold for about thirty minutes to burn excess fuel. Pan pan was declared. The crew also requested lower altitude in order to run the APU in attempt to burn fuel faster. The aircraft landing on 33R was uneventful. Fire services met the aircraft prior to tow to gate.
Mtc inspection found RH engine pump case drain chaffed and leaking as well as pylon hydraulic return line chaffed. Both lines, #2 engine driven pump and associated filters were replaced, and the aircraft was returned to service.
As the FAA filed it
WHILE IN CRUISE ENROUTE FROM YYZ TO CHS, CREW ENCOUNTERED A HYD 2 LO QTY EICAS MESSAGE. AT THAT TIME QTY WAS AT 22%. WITHIN FIVE MINUTES HYD 2 LO PRESSURE AND THE QUANTITY WAS AT 0%.
ATC WAS ADVISED THAT THE FLIGHT NEEDED TO RETURN TO YYZ DUE TO WEATHER CONCERNS IN CHS. CREW CARRIED OUT HYD 2 LO PRESSURE QRH CHECKLIST AND LOSS OF HYDRAULIC SYSTEM 2. THE AIRCRAFT WAS OVER MAX LANDING WEIGHT BY ABOUT 630KGS INITIALLY, AND CREW ADVISED ATC THEY WOULD REQUIRE A HOLD FOR ABOUT THIRTY MINUTES TO BURN EXCESS FUEL. PAN PAN WAS DECLARED. THE CREW ALSO REQUESTED LOWER ALTITUDE IN ORDER TO RUN THE APU IN ATTEMPT TO BURN FUEL FASTER. THE AIRCRAFT LANDING ON 33R WAS UNEVENTFUL. FIRE SERVICES MET THE AIRCRAFT PRIOR TO TOW TO GATE.
MTC INSPECTION FOUND RH ENGINE PUMP CASE DRAIN CHAFFED AND LEAKING AS WELL AS PYLON HYDRAULIC RETURN LINE CHAFFED. BOTH LINES, #2 ENGINE DRIVEN PUMP AND ASSOCIATED FILTERS WERE REPLACED, AND THE AIRCRAFT WAS RETURNED TO SERVICE.