The Significance of Q in Communications - Security Boulevard

The Significance of Q in Communications

A very long time ago I was in Chicago meeting with the man who wrote the security system for IBM’s AS400. I asked him “but why a Q” as we discussed the QSECOFR account.

He said it was a rare letter, denoting something special, and I had no reason to doubt him. This man claimed to have created the system for IBM and chose a Q for the simple reasons he said.

It’s true Q is rare. There’s only one Q tile in Scrabble and it has 10 points assigned (highest possible).

And it’s true such a letter would seem unique and distinctive and therefore sensible for special system communications.

Then many years later I was sitting on a train as the whistle blew several times when a pattern suddenly sounded familiar…

Two longs, a short and a long: – – . – (LLsL)

In international Morse code that signal pattern is the letter… wait for it… Q.

I did some searching and sure enough Union Pacific guideline (PDF) says Q is designated as crossing warning:

5.8.2 [7] Sound: — o – Indication: When approaching public crossings at grade, with engine in front, sound signal…. Prolong or repeat signal until the engine completely occupies the crossing(s)…

Prolonging the signal until the engine is in the crossing probably explains why a letter would be preferred that ends in long instead of a short. Engineers can just hold the signal open until they’re parked.

However, I needed more. So from there I poked around the history of Q-codes in Morse, a list of special communications started around 1909 to facilitate transmissions.

Here’s part of a table of 1912 in a UK government handbook of wireless showing some of the basics (initially just 12 Q codes):

Source: Handbook for wireless telegraph operators working installations licensed by His Majesty’s Postmaster-General : revised in accordance with the Radiotelegraph Convention of London, 1912.

Today we have “your mute button is on” and “you’re breaking up” in video calls but in the 1970s radio operators could use QLF to indicate “try sending with your LEFT foot” and QNB? for “How many buttons does your radio have?”

Amusing of course, yet still no deeper meaning for Q. It did little more than backup the story that IBM had used Q to emphasize uniqueness in system communications.

A book from 1952 called Thudbury however, gave this funny explanation:

I’ve heard that signal started on the Chicago, Burlington & Quincy line that everybody calls the ‘Q’ and just spread…

A similar sounding story from geography is found in a history of Britain’s Q fleet (“naval vessels that officially didn’t exist; the mystery ships of World War One”) designed to deceive, trap, and destroy German U-boats:

While in the dockyards, the mystery ships were known under various names, from decoy ships, which gave the game away somewhat, to “Q-ships”, or “S.S. (name)” ships. The “S.S.” in this case stood for “Special Service (Vessel)”. The “Q”, it’s suggested, was because they were operating from Queenstown, now Cobh, in Ireland.

Neither Queenstown for ships nor Quincy for trains are very convincing origin stories. A more likely possibility to me is that use of a Q flag on ships (yellow jack, Quebec) is an old signal meaning “I am ready for boarding” in harbor (a formal request for “free pratique“).

…ships signal either “My vessel is ‘healthy’ and I request free pratique” with a single Q (Quebec) flag or “I require health clearance” with the double signal QQ (Quebec Quebec). Either is correct for a vessel yet to be cleared for pratique (pratique is permission to do business at a port, granted to a ship that has met quarantine or other health regulations). The Q (Quebec) flag is square in shape and pure yellow. Continuing to fly either of these signals indicates a vessel is yet to receive clearance (and is thus effectively in quarantine).

Thus a Q ship in 1914 also could have been a play on words; an invitation to the enemy to come closer and be ambushed.

It’s an interesting point to consider how Q for ships meant ready for boarding by local authorities (“effectively in quarantine”) when entering a harbor, yet Q for trains was taken to be the opposite and a warning for everyone to move away from them. Or are those two the same thing?

Some theories on the Internet include bits of Q stands for the Queen Victoria in England and royalty on ships or trains would use a Q to indicate their right of way.

According to W. M. Acworth in The Railways of England, whenever the Queen travelled by train, special precautions were taken. All work along the line was stopped, the points were locked, trains going in the opposite direction were halted and level crossings were closed and guarded.

Here’s another version in video format:

Back in the time when the queen traveled by ship in England, ships with the queen on board would do this sequence on the horn to announce to other ships in the harbour to get out of the way. When the queen switched to railways, the same signal followed and the Engineer
would do the sequence coming into a station to allow some space for Her Majesty.

The problem I have with these takes is nothing yet seems to actually support such royal use for the letter Q (I mean why not use K for King?), not to mention ships and trains seem to have landed on opposite ends with their meanings.

Speaking of Queens and right of way, the Q was repurposed recently allegedly by someone with a signals or intelligence background who called themselves “Q Clearance Patriot” in reference to DOE’s Q level of access authorization.

And it now amounts to be a symbol of fascism extensively used by right-wing groups to signal intentions to replace democratic norms of law and order with “permanent improvisation“.

Here you can see an infamous image posted by the White House on their Twitter account showing Florida law enforcement and US Vice President are all smiles around a very prominent red “Q patch”:

Source: White House, as archived by and reported by

That man in the image is I suppose the physical manifestation of someone who wanted to elevate to QSECOFR by applying a Q to himself yet instead “he ‘discredited the agency, the country and himself’” and lost his system privileges.

*** This is a Security Bloggers Network syndicated blog from flyingpenguin authored by Davi Ottenheimer. Read the original post at: