Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Dassault Aviation Model Mystere Falcon 900 series airplanes. This proposal would require replacement of the water heater control relays with improved relays having high-power contactors; the addition of a testing and monitoring circuit for each contactor; and installation of improved electrical bonding of the potable water tank. This proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to prevent overheating of the water heaters for the galley or the washbasin, which could result in damage to the water heater and nearby electrical wiring, and consequent smoke in the cabin.