Airworthiness Directives; Boeing Model 727 Airplanes

The FAA is adopting a new airworthiness directive (AD) for all Boeing Model 727 airplanes. This AD requires determining whether any float switches are installed in the fuel tanks, and corrective actions if necessary. This AD results from reports of contamination of the fueling float switch by moisture or fuel, and chafing of the float switch wiring against the fuel tank conduit. We are issuing this AD to prevent such contamination and chafing, which could present an ignition source inside the fuel tank that could cause a fire or explosion.