Sydney Morning Herald reporting following at:
Qantas 747's galley leak caused system failure: ATSB report
A water leak in the galley of a Qantas 747 jumbo jet knocked out electricity to a series of systems during a flight to Bangkok, leaving pilots just minutes to land on battery power.
Water flooding in the galley knocked out three of the four on-board power generators, including all AC-powered systems, as the plane was on descent 25 kilometres from Bangkok airport.
Air investigators say that if the flooding had occurred more than 30 minutes' flying time from an airport or had there been a delay in landing, it would have placed the plane — carrying 346 passengers and 19 crew — "at considerable risk" as more systems were likely to fail.
The leak had already knocked out power to radar, cabin pressurisation, autopilot, auto-throttle and some fuel pumps as the plane descended from 21,000 feet and passed through 10,000 feet. The batteries, which were designed to last a minimum of 30 minutes before depletion, had been running for 21 minutes when the aircraft landed and taxied to the terminal building, investigators found.
The drama began when the galley flooded on the Qantas Boeing 747 due to ice formation that blocked a drain pipe after an anti-ice heater failed.
A build-up of water flowed forward and cascaded through a decompression panel into the aircraft's main equipment centre, leaking onto three of the jumbo's four generator control units, causing them to malfunction and shut down.
The 114-page Australian Transport Safety Bureau report released today into the January 7, 2008 incident said plane was reliant on its battery back-up for the last 15 minutes of flight.