Site Name:RAF Saxa Vord ('AXA') CEW R10 ROTOR Radar Station
Sub Brit site visit 4th June 2004
[Source: Nick Catford & Ian Brown]
In February 1940 instructions were issued by the Director of Signals Development at the Admiralty for construction to began on Admiralty Experimental Station (AES) No. 4 on the island of Unst in the Shetland Islands.
Photo:Panoramic view of RAF Saxa Vord in the 1987
Photo from RAF News
The final stage of the ROTOR Programme (Rotor 3) was to provide radar cover for the north and west of the British Isles which were still exposed to attack and to give low and surface level cover over the Atlantic, the absence of which prevented effective action against low flying enemy aircraft. Three new Centimetric Early Warning (CEW) stations were to be built at Saxa Vord, Aird Uig and Faraid Head equipped with Type 80 Mk 2 and Type 13 radars . The new CEW operations buildings were to be above ground and designated R10, similar in internal layout to the underground R1 bunker.
Photo:The R10 Operations Block. The three storey building to the rear housed an Admiralty Experimental Station. It was originally a single storey building,
the other stories being added at a later date
Photo by Nick Catford
ROTOR 3 included five new Chain Home Extra Low (CHEL) stations equipped with Stage 1 radar equipment to enable detection and tracking of low flying aircraft. (Stage 1 could comprise of Type 7 Early Warning [E/W] GCI, Type 14 E/W search radar E/W or FC [CEW station], Type 13 H/F and a Type 15 [mobile Type 7]) The proposed stations were at Kilchiaran, Murlough Bay, Prestatyn, Snaefell and West Myne. These were to be brick built operations blocks, designated R11; the above ground version of an R2 bunker.
Two new GCI stations were also proposed as part of the ROTOR 3 programme, each equipped with a Type 80 radar and R8 prefabricated operations block. One at Ballywooden (Killard Point) in Northern Ireland and the other at Wick on the Scottish east coast.
It was hoped that The ROTOR 3 programme would be complete by 1957 and all technical aspects were classified as 'Super Priority'.
Photo: Type 80 radar at RAF Saxa Vord in 1957/8
Photo by Terry Luxford
A 1956 Works File (Air 2/12064 - 6) lists the radars
and equipment that were to be fitted at Saxa Vord. These include Stage
1A (Type 80) radar on the site of the WW2 Chain Home Low operations
block with three Type 13 height finders. All evidence of the CHL was
cleared away during the construction work.
As the operations block was to be located 35 metres below the Type 80 modulator building the two sites were to be linked by 200 concrete steps which were later covered over to provide the covered way that is still in use today. There was also to be a Canberra style guardhouse (now demolished) at the entrance to the technical site.
One major problem did, however, have to be overcome. The erection of the Type 80 was seriously delayed when, in January 1956, the aerial array was blown completely off its mounting and ended up 50 yards downwind. The array of the Type 80 had been tested during the design stage and it had been shown that it would continue to rotate in winds up to 80 miles per hour. In winds exceeding that speed the array would `weather-cock' and thereby survive winds up to 120 mph. However, the radar station holds the unofficial British record for wind speed, which in 1962 was recorded at 177 mph; just before the measuring equipment blew away. This was clearly well in excess of the speeds which the aerials were designed to survive. It was decided in view of such weather conditions that a radome should be built over the aerial array and, with Saxa Vord providing cover of value to NATO, the latter organisation provided the radome, while the RAF, in the form of No. 91 Signals Unit, operated the radar from 1957 onwards.
Following the demise of ROTOR the air defence of the UK was reorganized once again. ROTOR gave way to a system of 'Master Radar Stations' (MRS) that provided radar coverage of the UKADR, the United Kingdom Air Defence Region. In the mid 60's MRS's started to give way to the 'Linesman/Mediator' system that was served by radar's from RAF Saxa Vord in the north of the Scottish Shetland islands, RAF Buchan, near Peterhead, Scotland, RAF Boulmer in Northumberland, England, RAF Staxton Wold in Yorkshire, England and RAF Neatishead in Norfolk, England.
The height finding element of the Linesman system, the HF 200 succeeded the American AN/FPS-6 height finder radars used in the ROTOR system. The HF 200's (along with the AN/FPS-6) were also known as 'Nodding Horrors' and they spewed hydraulic oil everywhere. HF 200 Mk3's were located at the three main linesman sites at R.A.F. Boulmer, R.A.F. Staxton Wold and R.A.F. Neatishead while a Mk4 was commissioned at R.A.F Saxa Vord in in 1979.
For further information and pictures of RAF Saxa Vord click here
[Source: Nick Catford & Ian Brown]
Last updated 21st May 2008
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