G-AOBN - The Radio Calibration Unit

The History of a long serving Douglas C-53
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G-AOBN started its life as a Douglas C53-D "Skytrooper", this was a specialised paratroop version of the C-47 Skytrain, and she was built in 1943 and delivered to the US Military on 18th May 1943.

She saw service in Europe and was bought by Swedish operator AB Aerotransport (ABA) and entered service with ABA on 19th October 1945 as SE-BAU and was named "Uven", she was named after a small island off the South East coast of Sweden.
ABA became part of Scandinavian Airlines System (SAS) in 1948 and our C53 transferred into the SAS fleet retaining the same registration but she was renamed "Ubbe Viking" after Ubbe Ragnarsson. He was a Norse leader during the Viking Age and was one of the sons of Ragnar Lodbrok, who along with his brothers Halfdan and Ivar the Boneless, were leaders of the Great Danish Army.

After three years of service with SAS she was sold to Cie Aerienne de Tpts Indochinoise (CATI) in February 1951 and registered F-OAIF.


In 1953 CATI was renamed Air Outre-Mer and to the right we have a photo of  her in AOM livery circa 1954.
In April 1955, our C53 was bought by Air Kruise and transferred to the British Register as G-AOBN, she was based at the busy Ferryfield airport and was soon flying Air Kruise's busy inclusive tour charter (ITC) routes to the near continent. By the Summer of 1955 Air Kruise had six Dakota's and destinations included Geneva, Turin, Venice, Salzburg, Copenhagen, Ostend and Lyon; they flew 36,500 passengers by the end of the year.

Below a postcard of G-AOBN on the flightline at Ferryfield.
Earlier, in 1953, Air kruise had become part of the British Aviation Services Group and was a sister airline to Silver City. Silver City also flew services from Ferryfield and had concentrated on their Air Ferry services. Though they were also transporting passengers on charter services and the decision was made to combine the operations of the two airlines. Air Kruise was merged into Silver City and in October 1957 G-AOBN was registered to Silver City.

She flew without a name while with Air Kruise, but the name "City of Canterbury" was given to her when in Silvery City's colours.

For two years she plied the skies flying passengers for Silver City, but they had other plans and she was converted into a Radio Calibration aircraft in November 1960. The work was undertaken by by Air Couriers at Gatwick. Below a photo of Bravo November in her new role.
Silver City soon won a five year Ministry of Aviation contract and she left on a tour to Cyprus, Bahrain, Lagos, Kano and Accra. They soon won contracts both world-wide and within the Commonwealth for the calibration of radio aids at airfields.

The mainstay of Silver City's work was still vehicle ferry services but by the close of 1961 it was becoming clear that Silver City did not have the resources to compete their main competitor, Channel Air Bridge (CAB). Channel Air Bridge were part of the Air Holdings Group, owners of British United Airways.

On 23rd January 1962 the announcement was made that the share holders of the British Aviation Services Group had agreed to exchange their shares for shares in Air Holdings. Silver City became part of Air Holdings, and AOBN was registered to Morton Air Services, who where an operating specialist services within the group. Below a photo of AOBN in British United Radio Calibration Unit titles, she is outside of the wooden hangar, Morton's hangar, at Gatwick.
The Radio Calibration work continued with many tours being flown by our C53. In November 1968 she became part of British United Island Airways fleet following BUA's rationalisation of it's divisions, BUA (CI), BUA Manx and Mortons.
BUA had been sold by Air Holdings in May 1968 to British & Commonwealth Shipping but the Radio Calibration Unit had been working away as always and in In February 1970 the Radio Calibration Unit (RCU) was awarded a contract for work in Saudi Arabia and the Gulf and they set off on their 38th and last tour for BUIA.

British & Commonwealth had been trying to sell BUA since early in 1970 and in July 1970 G-AOBN was transferred to British Island Airways, BIA would operate seperatly from BUA, though they would both still be owned by British and Commonwealth Shipping for the time being.

In November 1970 BUA was taken over by Caledonian Airways to form Caledonian//BUA. British Island Airways were not part of the takeover, BIA, and AOBN, were no longer part of Caledonian//BUA and the histories diverge. Below are some photos of AOBN in service with BUA before we conclude her history
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G-AOBN would fly for BIA before being sold in 1971, but she would then fly on for smaller British carriers Air Anglia, Air Freight Limited and Skyways Cargo before being sold abroad.

She was bought by Ethopian operator RRC Air Services (Air service of the Relief and Rehabilitation Commission) and was registered ET-AGR on 20th July 1977.

Though, her time was fast running out and just 3 weeks later, on 12th August 1977 - aged 34 years old, she was destroyed whilst on the ground in and air raid on Jigiga Airport in Ethiopia.