軍士長
Sergeant major signals (SMS) is a British Army appointment, formerly known as sergeant major instructor signals (SMIS). Normally a warrant officer class 2 in the British Army, selection for this post was the culmination of many years of experience with modern radio communications systems. During their careers it was possible to be trained in several evolving systems for example the movement from Larkspur and Clansman to the more recent Bowman radio communication equipment. Their duties included training personnel by the development and execution of in-house and in-theatre courses, keeping their signal sergeants up-to-date with amendments to policies and equipment, equipment husbandry, equipment procurement and high level custodian protection of electronic and paper codes. They had to produce communications electronic instructions containing relevant daily frequencies and associated information for radio operators.