WHILE CLBING THROUGH FL350; AN ACR EXPERIENCED A LOSS OF PRESSURIZATION WHICH NECESSITATED AN EMER DECLARATION; AND A RAPID DSCNT.

Narrative

ON AN ACR FLT FROM IND TO MSP; ON MAR/SAT/95; WE EXPERIENCED A PARTIAL LOSS OF CABIN PRESSURE; WHILE CLBING THROUGH FL325. THE CABIN ALT CLBED TO 11500 FT. THE PNF DECLARED AN EMER; AND STARTED A RAPID DSCNT IN ACCORDANCE WITH EMER PROCS. WE DSNDED THE ACFT TO 10000 FT. THE CABIN ALT STABILIZED AT 7400 FT AND WE CONTINUED TO MSP AT 10000 FT WITHOUT FURTHER INCIDENT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. THE RPTR STATES THAT THE PNF DECLARED AN EMER AND AN IMMEDIATE DSCNT WAS INITIATED; IN ORDER TO KEEP THE CABIN FROM CLBING ANY FURTHER. THE FLT DECK CREW DONNED OXYGEN MASKS ON A 727-200 WHEN A FAIRLY RAPID CABIN RATE OF CLB WAS NOTED -- BEGINNING WITH 6500 FT TO 11500 FT. AFTER LNDG; THE SO HEARD FROM THE MECH THAT THE PROBLEM WAS PROBABLY RELATED TO AN OUTFLOW VALVES FAILURE TO CLOSE. THE RPTR STATES THAT THE FLT WAS GIVEN EMER PRIORITY WITH CHICAGO; BUT THAT MINNEPOLIS WAS UNAWARE OF THEIR HAVING DECLARED AN EMER. THE AURTHORITY WAS ACTUALLY EXERCISED A SECOND TIME; TO PRESERVE MINIMUM ALTERNATE FUEL. A WRITTEN RPT WAS NOT REQUESTED BY THE ADMINISTRATOR.