Summary
We propose to adopt a new airworthiness directive (AD) for certain Boeing Model 737-100, -200, -200C, -300, -400, and -500 series airplanes. This proposed AD would require replacing the existing straight-to-90-degree hose assembly for the Lavatory "A" water supply. The replacement is a new straight hose assembly and a separate 90-degree elbow fitting. This proposed AD results from a report of a separated hose assembly for the passenger water system. We are proposing this AD to prevent a water leak into the flight deck ceiling, which could result in an electrical short and possible loss of several functions essential to safe flight.