Established in 1921, the Signalman (SM) rating was absorbed into the Quartermaster (QM) rating in 1948, only to be re-established eight years later. Its status remained unchanged, with no service ratings or other additions, until 2003, when it was once again included in the Quartermaster rating.
Specializing in visual communications using flags and powerful lamps, Signalmen transmitted and received messages—sometimes encoding and decoding them in the process—from line-of-sight sources. Such a system might seem primitive in today’s world of digital telecommunications, and the very fact that it was limited to only what could be seen, it still has one advantage: Unlike wireless transmissions, messages sent via visual communications are almost always seen only by the intended recipients.
Sailors in the SM rating employed three main methods of communications: Semaphore, Morse code, and flaghoist signaling. Semaphore is a system where each arm can be positioned to point in one of eight directions (similar to the eight main points on a compass); the combination indicates a numeral or letter. Visual Morse code works identically to the original telegraph version but uses flashes of light of varying lengths to replicate dots and dashes. Flaghoist signaling relies on flags of different colors, patterns, and sometimes shapes to indicate numbers and letters.
When the Navy disestablished the Signalman rating in 2003 and shuttered the doors to the Signalman Class “A” Schools around the country, the duties of the rating were given Quartermasters. Although such a move had been rumored for years, many were surprised by the decision because the current crop of Quartermasters at the time were completely unfamiliar with the tasks performed by Signalmen. Sailors in the SM rating when the decision was announced were given the opportunity to convert to another rating, with many choosing selecting Master-at-Arms due to the increase need for them that was an unexpected result of the Global War on Terror.