According to the Federal Register of the United States government on July 29th, the Federal Aviation Administration (FAA) has recommended the adoption of new airworthiness directives (AD) for certain Boeing 737-300 and -400 series aircraft. The proposed airworthiness directive was triggered by a report stating that flight control rigging tolerances may result in spoilers being unable to deflect to the minimum level required by the cruise thrust separation monitor (MONFD) used by the automatic throttle (A/T) system. This proposed AD will require the replacement of certain wiring harnesses, installation of new housing components, removal of mechanical aileron force limiters (MAFLs), inspection or record checks to determine if certain flight control computers (FCC) have been installed, and applicable conditional actions. The FAA proposes this AD to address the unsafe conditions of these products.