Mandatory service bulletin. Service bulletins (SBs) are issued by the original equipment manufacturer (OEM) and describe changes to be made to their aeronautical products. . When used in this way, the content of the bulletin is a condition of type certificate, and compliance is mandatory. " Service bulletins are automatically sent to the owner of an aircraft by the aircraft or component manufacturer. Oct 23, 2017 · "Depending upon the manufacturer, a service bulletin may also be called a "mandatory service bulletin," "technical service bulletin," "service letter" or "service instructions. For the purposes of this discussion, the term mandatory means “required in order to maintain a valid FAA airworthiness certificate. If you are operating under 14 CFR Part 121 or Part 135, which pertain to air carrier and operator certification, or the service bulletin is attached to an airworthiness directive, it may be considered mandatory. ” Service bulletins are automatically sent to the owner of an aircraft by the aircraft or component manufacturer. Mar 1, 2003 · Is a manufacturer's mandatory service bulletin mandatory or not? This topic pops up in hangars regularly and tends to polarize A&P's and IA's alike. Date on which this Mandatory SB becomes effective and must systematically be complied with, according to the conditions of application. cgxrj tak edqvb jukec bujw miu rnf vjh ycri ogkpkn