Pundit Code

A Pundit Beacon or Landmark Beacon was an airfield navigational and identification beacon, used by the British Royal Air Force (RAF) in the period around World War II.

Each airfield was allocated a unique two letter Pundit Code, usually based on the name of the site, such as 'BL' for RAF Beaulieu. By the mid-war period the increasing number of airfields led to overlapping names. New codes were allocated by using the previously little-needed letters 'I', 'J', 'Q', 'U', 'V', 'Z' or 'X'. Harrowbeer thus became 'QB'. Some pre-war beacons had initially used a single letter code, but these were re-allocated two letter codes to avoid confusion with the lighthouse beacons.

Codes were visible from the air, with 10-foot (3.0 m) high letters displayed alongside the Signals Square and Watch Office, usually near the control tower. Established airfields had concrete letters set into the grass, as still survive at Beaulieu. Temporary or hurriedly constructed airfields used simple white paint on the tarmac.

By 1937, all airfields used for night flying were also equipped with a Pundit Beacon. This used red lamps to flash the two-letter Pundit Code in Morse. The beacon was visible all around in azimuth. The Morse code sequence was programmed for each beacon with a disc sequencer, a rotating disc with a ring of brass studs placed into it.

During wartime the red beacon became a familiar marker for returning bomber crews, signalling the end of a mission.

A Pundit Light was a mobile Pundit Beacon.

As well as the obvious ability to move these mobile lights to temporary airfields they were also used to camouflage the airfield location from the enemy. The normal peacetime beacon location or light code was no longer used. Instead a mobile light was placed at one of three positions some distance from the airfield and a different wartime code was used: Elmdon (EK) used JD / KJ / UT in war, Ringway (EZ) used CL / HV / JL. The codes and their offset to the airfield location were distributed to flight crews and would change periodically. If an air raid was in progress at the airfield and so returning aircraft should divert elsewhere, its light location would also indicate this by also displaying a triangle of red lights surrounding it.

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