Tuesday 31 July 2018

A History of RAF Skaw (AMES 56) - Part 5 - Some of the Other Buildings at RAF Skaw


The Advance Chain Home element of RAF Skaw was the primary operational unit until the main Chain Home equipment was commissioned in May 1942. Indeed questions were asked by higher authorities about the reasons the full stations at Skaw and Noss Hill had taken so long to complete. Similar stations on mainland UK took about 12 months less to finish. Bowler- hatted civil servants and expert scientists didn't always appreciate the problems of sea crossings, weather and the lack of infrastructure at some remote locations, particularly when there was a war going on!. The Transmitter and Receiver blocks were described in an earlier section (Part 4) so it's time to look at some of the other structures. Guard posts, gun positions  and other defensive measures will be considered in yet another section.
Early in 1940 the first radar unit to arrive on Unst, No 3 Transportable Radio Unit (3TRU) , was assembled on the Keen of Hamar:  http://ahistoryofrafsaxavord.blogspot.co.uk/2013/01/the-first-radar-on-unst.html    When that Unit was suddenly closed in August of that year some of its equipment was left behind. Explosive demolition charges, designed to destroy the sensitive, highly classified radar components, were passed on to the Admiralty Experimental Station on Saxa Vord, which lacked the items. 3TRU also arrived on the island with about 8 wooden huts and I believe these were also left on behind and used as part of the accommodation when the construction of RAF Skaw began.
Power. Unst was not on the National Grid so the RAF had to supply its own power. Arrangements for generating electricity for the Advance Chain Home equipment and for the Skaw Remote Reserve are outlined in Parts 2 & 7. The Main Power House (MPH) was located just to the north of the road running through the centre of the camp and about half way between the camp gate and the Receiver Block. It was a large, rectangular building with a pitched roof. Overhead pictures of the area, including one from 1946,  give no indication that it was camouflaged. The building is now in a very sorry state with no roof and with the interior deeply covered in sheep manure.  In this, more recent photo, a dome on Saxa cam be seen to the left of the Power House with a later building behind the old structure:

The main generating plant in the MPH consisted of 2 Blackstone EPV4 sets. In 1936 Blackstone & co were taken over by the Lister co, which also manufactured power plant, but the equipment in use at the main Skaw site was of a type originally produced by Blackstone. Both sets were used to allow maintenance and to equalise wear.   The serial number on the equipment were recorded as: EPV No. 45297 and EPV No. 45286.  The inside of the building a few years ago can be seen in the next photo:

Some idea of the logistical problem can be envisaged when the fuel consumption is examined. On average about 212  barrels of diesel were used in a day and, if we assume it came in 40 gallon drums, then nearly 3 tons of diesel was required each week. Getting the fuel to Shetland, then to Baltasound and then to the camp would have been hard work! Someone, knowing the problems of the remote location, decided that the station should maintain a minimum stock of 5,000 gallons of fuel oil! When operational the MPH provided power for the radar and general lighting. Heat for the billets was another matter - large supplies of coal were also needed to feed the stoves in each hut.
During 1942 a cable was laid from the Power House to the top of Saxa Vord, a distance of over 2 miles. It was needed to provide more power for the naval radar equipment (Type 273, a - centimetric radar) being installed at the Admiralty Experimental Station No. 4. The new equipment on the naval unit went "live" on 2 Feb 1943.

As the Main Power House was a fairly "soft" target and, because there was no local civilian source of power, the RAF provided a Standby Power House - sometimes called a Standby Set (House). This was about 600 yards east of the Main Power House and closer to the Transmitter Towers. However, the standby equipment was in a bunker, protected by mounded earth:

In this next Flash Earth image at closer range, not only can the physical protection for the Standby Power House be clearly seen, but the perimeter of the old camouflage netting can also be detected, particularly to the SW of the structure

There were 2 Blackstone sets, just like the Main Power House, they were numbered EPV 45307 (No. 1) and EPV 45402 (N0. II). All the WWII equipment was removed long ago and, in more recent years it has been used as a place for maintaining  local boats. I believe it has also been a site used in the past for the construction of the galley for the Norwick Up Helly Aa.

Identification Friend or Foe (IFF). Early on in the history of British Radar the risk of "friendly on friendly" action was recognised. Basic radar could obtain a response from an aircraft but the operator might need help in deciding whether or not the aircraft was a threat. On 6 Sep 39, just 3 days after Britain entered the war, an RAF pilot died in a friendly fire incident. Attempts were made to improve the air defence system and, by the beginning of the Battle of Britain, a rudimentary set of equipment, nicknamed "Pip Squeak", was  installed in a number of RAF fighters. The kit caused the H/F radio in the fighter to transmit a signal at specified intervals, it allowed a fighter or a group of fighters, to be tracked by the radar stations.

Further developments led to IFF, whereby the radar operators used ground equipment to transmit a signal to "interrogate" aircraft. Friendly aircraft were equipped to react to this interrogation and to send a separate signal back to the ground using an item of equipment known as a "transponder". IFF developed fairly rapidly but I have seen no record of the type installed in the early days of Skaw. The first operators for the Advance Chain Home  ACH equipment, who arrived in Nov '40, were supplied with a 105' masts/s, but whether for radio or IFF I don't know. It is quite possible that the ACH IFF at Skaw was similar to the one on an operations hut at the Chain Home Low site at Clett, Whalsay - just 30 miles away. This is what that aerial looked like in1942, the smaller aerial, closer to the photographer, was for the IFF.

It is known that the Skaw main Chain Home station had an operational version of Mark III  IFF in 1943. The next picture is an extract of a photo, taken in 1944, by a serviceman called Derek Lucas. It shows the Skaw Transmitter towers on the left, the Receiver towers on the right and, just visible, the 105' IFF mast in the middle:
The next picture, from the SD4058, shows what the installation looked like (albeit in a wooded area!):
The mast was held upright by cables (guys), attached to anchor points. The photo below shows one of the anchor point  (marked by an arrow) and the IFF building - known as a cubicle or Kiosk - is on the right (with a sheep on guard in the door way!)
The entrance was protected by a blast wall, from floor to ceiling the cubicle was 7' high and the  internal floor measure. 6' X 6'. Just behind the cubicle the remains of the  ACH transmitter and generator blast walls can be seen in the next picture. The base of the 105' mast was mounted on a rectangular concrete foundation, just to the north of the building, and is clearly visible in the photo.
Civilian Dwellings. As mentioned in Skaw Part One, the area of RAF Skaw had to be requisitioned from John & Helen Priest, whose house (called Ivy Cottage),  lay at the western edge of the land used by the RAF. The Priests had to move out and, as far I know,  Ivy Cottage remained unoccupied throughout the war. The location of Ivy Cottage, just east of the main Domestic Site, was shown in Skaw Part One. Two other families remained living within the camp boundaries, at least for some of the Stations life. Two "quarters" were allocated to the Cruikshank and Palmer families. These houses were, in fact, converted nissen huts similar to those occupied by some of the RAF. Each of the  huts used as "Quarters" had an associated air raid shelter and these are the only things which remain  to show where the two families lived:
Main Domestic Site. I have mentioned Ron Simkin earlier. He was a radar mechanic and served at Skaw from April '43 to April '44. He returned to Unst after the war and drew an excellent map of the Station and a more detailed plan of the domestic site. In fact, his detailed map of the domestic site is so accurate one might think that he had access to aerial photos!
 
A few  photos follow; firstly, some of the ruins of the buildings which lay on the south side of the road which ran through the centre of the camp:
 
 
 

The following photos are of the remains of some of Buildings on the north side of the road which ran through the Domestic Site, from the Camp gates towards the Operations Sites.
 
 

 
Moving eastward from the domestic site  there is what appears to be a quarry on the south side of the road. In it is the foundation of a rectangular building which is described as a " Maintenance Workshop"  on the Simkin map. I don't know what was being maintained but it is possible that the site had a previous use. By June 44 many Bofors guns were moved to the south of England for the D Day landings and to provide some defence against the V1 flying bombs. I haven't been able to discover when the Skaw Royal Artillery weapons were removed - the last reference I have seen to them was in May 43. However, an early Air Ministry Works Dept (AMWD) plan refers to an Anti-Aircraft Headquarters and Garage which seem to have been in this vicinity. The AMWD plan also states that the AA Garage was "blown away in a storm". Whilst I have no firm evidence I think it is likely that the AA Headquarters became a Maintenance Workshop later on in the war. A recent photo of the "quarry", with foundations,  is shown below:
Between the start of construction and final closure, the site of RAF Skaw was occupied for more than five & a half years. The quantities of cement and bricks used were vast and the use of pre-fabricated buildings (wooden huts and nissen huts) was widespread. The requirements changed as the number of people on the Station fluctuated and as the war progressed, with some structures used for different functions during their lifetime.  After the war most of the material used for the huts "disappeared" and some of the bricks were used for other purposes. However, many of the wartime elements of the radar station are still standing and waterproof!

Previous articles on RAF Skaw

Part 1 of RAF Skaw - Inception to Jan '41 is here:
http://ahistoryofrafsaxavord.blogspot.co.uk/2018/04/a-history-of-raf-skaw-ames-no56-part-1.html

Part 2 of RAF Skaw - Advance CH - From Jan 41 to May 42s is here:
http://ahistoryofrafsaxavord.blogspot.co.uk/2018/05/a-history-of-raf-skaw-ames-56-part-2.html

 Part 3 of RAF Skaw - CH Ops is here:
http://ahistoryofrafsaxavord.blogspot.com/2018/05/a-history-of-raf-skaw-ames-56-part-3-ch.html

Acknowledgements:
The late Lexie McMeechan
The Late Ron Simkin
Mike Dean
Bob Jenner
The late Leslie Smith
Rita Carle
Unst Heritage Centre
SD 0458  - Photographic Record of Radars stations  (Ground) - Air Ministry Aug 43
CONTENtS LIST