Extracted From:    AC No. 43-16A
            ALERT NO. 304
            November 2003

The pilot reported that, upon landing, he noticed a loss of pressure on the right side brake.

The technician discovered the right brake master cylinder was empty. He found that there was a hydraulic leak underneath the copilot floor. Further investigation revealed a corroded aluminum brake line (P/N 5100107-69) was causing the leak. The aluminum brake line had made contact with the air distribution ducts, which caused the corrosion. The submitter also stated he found similarly corrosion on the oxygen lines in the headliner on the same aircraft. The corrosion is caused when the steel support wire, in the air distribution duct, make contact with the aluminum lines.

Part total time-5,323 hours.