RAF Buchan and The Falkland Isles

Text and Photographs from John Dell

(Minor amendments 30/6/20 by John re roles of TSSU vs. USST)

 

S259 at Bishops Court 1984. TX/RX cabin in the middle, display cabin on the left, compressor pallet on the right. The wheels have been taken off all three units and stored under the canvas awning on the side of the display cabin.

Note the very professional-looking "sail", in this case made of aluminium.

Note the thin steel "guys" holding the aerial in place - they have had white tape fixed to them to stop people walking into them or tripping over them in the dark.

 

 

 

 

 

 

 

 

 

 

 

 

I saw my first S259 (it was usually called just the “two-five-nine”) mobile radar when I was posted to RAF Buchan in early 1978. At that stage Buchan had a Type 80 main radar and two American FPS6 height finders. The S259 was there as a backup in case the Type 80 was unserviceable for any reason. It was only powered up once a week for a brief test. I believe that it was occasionally taken to a site a mile or so along the A90 past the village of Longside and operated from there, but I never directly observed that myself.

A shot sent to me of the S259 at Buchan in 1982. Note the different "square" sail on this one. Knocked up from a bit of plywood.

 

 

 

 

 

 

 

 

 

The S259 at Buchan (along with the ones at Saxa Vord and Boulmer), had originally belonged to No 1 Air Control Centre (1ACC). 1ACC used to bring an S259 (or the earlier AN/UPS-1) up to cover for any major unserviceability or scheduled servicing but it was deemed more cost effective to leave the them on site permanently

 

At that stage I was not trained on the S259, but I did get shown around the inside. It seemed incredibly “space-age” compared to all the 1950s valve technology then at Buchan. Wow, it had transistors! At the same time the S259 had a reputation as a “dangerous” machine to work on. This was due to an accident with it when a popular, very competent, Chief Tech was electrocuted, he was very lucky to survive. He hadn’t been working on the radar, he had simply stepped inside to see how the technician working on it was getting on. The cramped confines of the cabin meant that if you swung any of the units out they blocked the narrow passage, and one of those units was composed of a metal frame at a very high voltage. He walked straight into it. Luckily the technician who was working on the radar was on the other side of the frame and could reach the emergency off switch.

At the end of 1978 into 1979 I went on a course at RAF Wattisham near Ipswich to be trained on the Marconi-Elliott 920C computer. This was done at a site on the far side of the airfield shared by 1ACC and USST.  At that stage 1ACC was winding down prior to disbandment. It shared the same site as the "Tinsmith"/SLEWC Support Team (TSSU). The two organisations were interdependent; the equipment of 1ACC was used by TSSU for training and other purposes. They had some (I can’t remember how many) S259 radars left. With the disbandment of 1ACC the S259 radars were given over to USST permanently and it was USST that took on the responsibility of plugging any gap in UKADGE coverage. One of the larger 1ACC American TPS 34 3-D radars went up to Buchan to complement the Type 80 and replace the FPS6 height-finders. At the same time some Autonomous Display equipment, in storage after being taken back from Singapore, was combined with a Marconi Elliot 920C computer and sent up to Buchan to form the “Buchan Interim Fit” (BIF) which was housed on the surface while the R3 bunker was stripped and refurbished.  The cables on the equipment from Singapore had been liberally sprayed with rat-poison when they were in storage and the GRIS fitting party doing the work of assembling and testing the equipment at Wattisham became dangerously ill!

At the start of the the Falklands War, all the S259s that could be found were quickly gathered up at Wattisham to be refurbished to be used in the South Atlantic, they even got one back from Troodos in Cyprus (I think the one at Saxa Vord was left where it was). I believe at least one of them was purchased back from a scrap dealer who had bought it only weeks before. One was sent down to Ascension Island to sit on top of the mountain (known as “Bowler Radar”). The disposition of the rest during the war is a matter for conjecture, but I know that shortly after the cessation of hostilities one was installed at the recaptured airfield at Port Stanley.

I was one of those hastily trained up on the S259 after the war. They needed a pool of trained technicians to serve the 5 month tours to the Falklands they put in place.  The training was done at Wattisham. By this time the "remains" of 1ACC and TSSU had been consolidated into one unit, called the UKADGE/SLEWC support team (USST). My course was very lucky in actually having a real S259 to train on (some subsequent ones were not so lucky and did training from the APs and Circuit diagrams only!). The site at Wattisham was only a few hundred yards from private houses and if the radar was switched on it would cause massive interference on TV and radio in the neighbourhood (anecdotally it also caused havoc with some remotely controlled sluice gates nearby). So training was a bit restricted by not being able to actually power up the radar transmitter (there was a big dummy load available but for some reason it was never used, I think maybe there was still considerable interference).

Shot of the inside of the S259 TX/RX cabin at the RAF Radar Museum Neatishead.

 

The S259 was a hybrid system – A Marconi  L-band transmitter and receiver mated to an old American AN/UPS-1 aerial with a display cabin that housed two Plessey Mk5 displays.  The thing consisted of three “bits” – the radar cabin which had the aerial mounted on top when it was in position, the display cabin and a compressor “pallet” which had the waveguide compressor on it, but which also held the aerial when it was broken up into bits for transport. All three units had a set of lightweight wheels attached for towing, and all 3 units and their wheels could be accommodated in a single RAF C-130 ( I stress that “RAF C-130” , the internal fitments of some other Air-Force’s Hercules made them too narrow to load it) . All it needed was a generator and fuel to provide power.  The use of the Plessey displays was to make it compatible with the same type of displays used by 1ACC. The use of the AN/UPS-1 aerial was dictated by the need for the equipment to be as small as possible for air transportation, but it probably saved the MOD money as well! I believe the S259 radars were simply the same cabins and pallet used for the earlier AN/UPS-1 with the transmitter/ receiver taken out and with the Marconi system shoe-horned into it – and it was a VERY tight squeeze.  So from the outside a S259 radar looked indistinguishable from the earlier RAF AN/UPS-1 except for a “twist” in the waveguide of the AN-UPS-1 after it left the cabin. (The US Marine corps also used a model of the AN/UPS-1 , in which the transmitter/ receiver was housed in a tent).

I seem to remember the documentation of the S259 was a bit vague in places. Obviously the documentation of the three systems that made it up were all there, just copied from the appropriate pre-existing AP (The Marconi radar, the AN-UPS-1 aerial and the Plessey displays). But just how they joined together was represented by just a single block diagram. However our tutor, Brian Matthews, was a brilliant teacher who used some very novel techniques to make sure we remembered everything!

I went South in mid ’83 and got taken off the SS Uganda straight to Ajax Bay. The only S259 in the Falklands at that stage was positioned on top of the hill overlooking Ajax Bay and San Carlos water on one side and the Falklands Sound on the other.  It was known as “Albatross Radar”.  The accommodation was in the old slaughterhouse at Ajax Bay and to get to the radar we had to climb the hill/mountain on foot.  The first time it took me 90 minutes to do the climb, by the end of my tour I could do it in 20 minutes. I was never able to figure out the history of the S259 at Albatross Radar.  It might have been the S259 sent down with the task force and originally set up on the airfield at Stanley; on the other hand I seem to remember someone suggesting that original S259 was returned to the UK and the Albatross Radar one was a different one sent down afterwards.

 

S259 Radar Albatross Radar 1983. Note no "sail".  The cabin was sunk into the ground about 3 foot and then a ring of earth-filled oil drums ran around it.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The hill/mountain that Albatross radar was situated on was covered in peat bogs. As we got into the summer months we had a long spell of sunny weather and the ground started to dry out.  This meant that the two earths of the ELCB protection would become different and power would trip out. With clean water a scarce commodity and all the puddles and streams dried up we fixed the problem by starting to pee on the one earth spike and then walking to the other earth spike while continuing to irrigate the Falklands  (there were no toilet facilities at the radar anyway - all solid waste was simply buried).

I never went to Mount Kent or any of the other FI radar sites. However, I was told that the S600 on Mount Kent had been deliberately placed so that the peak of the mountain came between it and our Radar at Ajax Bay so that the two would not interfere with each other! – Make of that what you will, I can only report what I was told.

I did go on what was laughingly called “R&R” to Port Stanley. It was supposedly for just two days, but the “FIADGE Support Team” who ran all the logistics for the FI radar sites had a habit of  “shanghaiing” people in Stanley to use as labour. This duly happened to my party and we found ourselves unloading and loading helicopters on the airfield for a week. However, this did give me a chance to poke around the S600 radar “convoy” that sat forlornly in the dunes. The transmitter and receiver looked very similar to that in the S259. When I asked what the plans were for it I was told that they hoped to use it to replace the S259 at Albatross Radar. I could not see that myself, the logistics to support it seemed to be of a different order than the little “boy scouts camp” required to keep the S259 going.

The tiny aerial of the S259 meant it had very pronounced “lobes”. It could, and did, pick up aircraft at 260 miles range, giving massive echos on the screen some 40 miles across. However, as an aircraft got closer it could disappear as it slipped between the different lobes. You only got a consistent, solid return within about 60-70 miles. The coverage was not helped by the positioning of the radar. The ideal position for an S259 (or AN/UPS-1) was a big concrete hardstanding on an open plain. Then the reflections off the ground would effectively make a larger aerial and fill-in the radar lobes. But the RAF insisted on putting them on boggy mountain tops.

The operation of the S259 at Albatross radar was often curtailed by the high winds experienced in the Falklands. The aerial horn would catch the wind, causing the aerial to slow down then get caught in the opposite direction and whip around at a high speed before slowing down again. Because of this, the radar was switched off in high winds and left to free-wheel to avoid burning out the motor. I should stress that this was exactly what the AP manual (copied directly from American AN/UPS-1 manual) said should be done.  We were even provided with an anemometer to measure the wind speed and had strict instructions at what wind-speed to switch off the radar.

What we didn’t know was that this problem was easily solved by putting a “sail” on the back of the aerial, so that the surface area of the radar horn was balanced by the same size area on the back of the aerial. Thus the force on one side of the aerial acting to slow it down was balanced by a similar force on the opposite side acting to speed it up, so both forces balanced out. This unofficial “mod” had been worked out previously by both the US Marine Corp and 1ACC on the original AN/UPS radar but for some bizarre reason was never adopted officially. Interestingly, in WW2 the Italians developed a dorsal turret for their CANT Z1007 bomber that worked on the same principal, the drag of the machine gun was balanced by a rod that stuck out of the rear of the turret. This meant the turret could be easily turned manually, whereas allied turrets needed to be power-operated to turn against the airflow on the gun barrels.

I know this because, after I did my tour in the FI, I found myself posted to USST and spent the rest of my time in the RAF working on the S259. When I was posted in there were two S259s there being refurbished.  An Irish Sergeant was posted in at the same time who had served a tour looking after AN/UPS-1 radars some years before. He took one look at the S259 radars and asked where their “sails” were. Everyone scratched their heads and wondered what he was talking about. He got permission from the unit CO to take a Landrover down to Henlow and came back with a complete “sail” assembly, very professionally made out of aluminium, which had been languishing in the corner of some compound down there for years. We brushed it down, gave it a coat of red primer and then green paint, a dayglo "flying pig" emblem  (the unofficial emblem of the unit) and stuck it on one of the S259s. A week or so later a gale blew across and we were very pleased to see that the aerial worked perfectly, going around at a constant speed in the high winds. Talk about re-inventing the wheel!  If you look at pictures of the S259 and AN/UPS-1 online you’ll notice that if they do have “sails” they all look different, that’s because they were all made on an ad-hoc basis from whatever material were at hand.

It was sometime in 1984 that the edict came down that the S259 was henceforth to be called the “Type 95”. Everyone still called it the “two-five-nine” except when the fierce, straight-laced WO was around.

One of the S259s, refurbished at USST while I was there, was loaned to the RDAF for use in the Faroe Islands. The installation of a Martello system there was running behind schedule and the S259 was put in as a stop-gap. It was mated with a huge American radar head left over from their previous radar system. With that aerial it gave a fantastic performance, pinpoint target echoes, nearly as good as the legendary Type 80.

We took the other S259 over to Bishops Court in NI as a stand-in while their main radar was serviced. It was exhilarating flying into the old runway there in a C-130. After that it was sent down to the FI to serve as a stand-by system at Mount Kent.  Unfortunately there was no S259 left at Wattisham to train the new technicians required to service it, so they had to do it all from books with no practical experience.

One of the most important things when deploying an S259 was to make sure that the steel cables (carried on the compressor pallet during transport) to secure the radar aerial, were in place.  There were four of these to anchor the aerial to stop the whole cabin being blown over in high winds. We had been very careful to take photos of how this should be done on the S259 before it was sent South again, and all the courses had a slide-show presentation of how to go about doing this. However, apparently this was ignored and when the S259 was put onto Mount Kent the steel guys were not attached, and inevitably the cabin blew over.

Just as I left the RAF the unit, now with a captured Argentinian TPS43 "Type 99" on strength, was renamed 144 SU.

 

A lot of online commentaries on the Falklands War credit 1ACC with the preparation and deployment of RAF strategic radars during the conflict. This is wrong, 1ACC had essentially ceased to exist before the conflict started, a victim of the vigorous defence cuts then taking place. Although a strong "core" of ex- 1ACC personnel formed the nucleus of the effort, people were drawn from all over UKADGE under the auspices of of USST to get the job done. A remarkable feat of improvisation.

I hope that is illuminating and will preserve a few memories of the old S259 from an 'erks point of view!

 

Input from Dave Lowry:

I may have a few points to add to the S259 story that may be of interest. in 82 I was in the Fighter Controller post at RSRE Malvern but quickly involved in siting of firstly Rapier and then the AD Radars. I was then detached to the S600 and accompanied the radar down south in the RFA Sir Geraint. We arrived late 82 and set up on Canopus Hill as Mt Kent wasn't ready. An S259 was already on Canopus and the other at Ajax Bay. My personal understanding of the siting on Kent is that it was decided by people who didn't know or understand the operational picture.

 

Input from Stephen Pritchard:

Regarding the S259 in San Carlos. I think it possibly unlikely it was the task force one as one cabin had suffered damage to at least two of the airlift eyelets so could only be moved by road. I know this as I arrived at Stanley just after the conflict had ended and saw the damage. The damage had occurred during the passage south during a storm and couldn't be airlifted even if there'd been enough Chinooks! The story came from an old Saxa Vord colleague I met there. The S259 remained at Stanley during my time along with the captured (American built) Argentine 3D radar complete except for trigger boards. Word had it that we'd asked to buy new boards and the Americans were happy to sell provided we paid up what the Argentinians owed them for it!
I too was eventually at Albatross radar and slept in the same slaughter house and climbed the same hill and also improved my times! Can't remember if we called it Albatross back then. We didn't have an S259 but a captured Argentine mid-range radar. We had no earthing problems but did get a lightening strike on the generator which vapourised the ceramic in the fuses!
I left early December '82, avoiding the SWO and haircuts.

 

Recap from John Dell

Stephen Pritchards' comments on my memories of the S259 rang a bell - He says when he went to Ajax bay he worked on a captured Argentinian radar, not an S259.
Now when I first got there there was an Argentinian Radar there - It was all packed up ready to be shipped out by helicopter, but it had been in that state there for months. None of the people there had ever worked on it or knew anything about it. In fact until I read Stephen's comments I had no idea it had ever been operational and used by the RAF. I took a photo of the aerial all packed up - There was a
separate cabin which was down the hill a way.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

About a month after I got there both were taken away by Chinooks.
Whatever happened to it I do not know - It was not the big Argentinian TPS43 (type 99) radar that ended up at Wattisham.

 

 

"Earlier" Memories Of S259

Some supplemental stories from Mike Head

Staxton Wold in 1971

It was brought in to cover a low flying exercise in the Vale of York (The A64 road runs through the Vale of York from York to Scarborough). Because it was a low flying exercise, the S259 was not deployed on the Staxton Wold site, but part-way down the hill to the A64. Presumably the coverage angle of the antenna permitted an enhanced view that the main Staxton Wold search heads could not provide.

Cyprus 1974

(just after Turkish intervention in the Northern part of the island).

At that time there were 2 Air Defence Radar sites, collectively known as 280 Signals Unit, in Cyprus:

 

• Cape Gata, which was part of RAF Akrotiri and located on the coast cliffs beyond the runway. This location had one S259, another gantry-mounted search head (note from Peter Moore: I believe that this was a Marconi S319 - a 45ft single-sided L band antenna, fed by an SR1030 2.5MW Tx/Rx), an HF200 height finder and an operations bunker (this had been retrofitted with GL161 equipment recovered from Singapore/ Malaysia).

• The RAF Troodos technical site on Mount Olympus. This had one S259, one T84, one HF200 and an operations building; the display equipment was a bit of a hybrid between Rotor and Rotor Phase 1.

On a previous visit to Cape Gata, in 1970, the S259 had yet to be delivered/installed.

The S259 installation on Mount Olympus was different to the standard set-up. The location was subject to extreme snow fall during the winter and soon covered the shelter and the antenna and the S259 was placed in its own building with a radome. One year the snow covered the perimeter fence, requiring the army to install  a roll of barbed wire on top of the fence, only for it to snow some more and require a further roll of barbed wire.

To enable a clear surveillance pattern the Mount Olympus S259 turning gear and antenna was detached from the shelter and mounted something like 10 metres above the shelter on a platform under the radome.

The Mount Olympus S259 was interfaced into the operations building for use with the Rotor/Phase 1 display equipment and would be bought into use whenever the T84 was unavailable.  The difference in the turning supply frequency (S259 was 400 Hertz and Rotor equipment was 50 Hertz) required careful handling.

By mid 1975 the effects of the disturbances the previous year had caused many of the RAF aircraft to leave Cyprus and another Defence Review had taken place. Cape Gata was closed, the S259 and GL 161 equipment from Cape Gata were repatriated to the UK. The other search radar at Cape Gata was dismantled (the antenna was certainly cut up) and scrapped. The major equipments had their titles codified by the Near East Air Force (NEAF) for reporting purposes, the S259s were Tango 1 and Tango 2; when the Cape Gata equipment was repatriated, the Mount Olympus commonly became known as the Last Tango in Cyprus (in recognition of a popular movie production of that era).

The Mount Olympus S259 was still in place and operating into 1976, when the T84 radome had a long maintenance period.

The S259 had a period of some months of unavailability when the pulse transformer was diagnosed as faulty and no spare was available. What wasn’t known was that when it had been stripped down all the earth straps in the cabinet to all the individual frames had been removed and then not reinstalled, causing random tripping at below-optimal EHT.  Only after several hours of testing did we find that, when test equipment was grounded on the chassis, things did improve.
The S259 had a very strong permanent magnet for the magnetron. There was a screw-in brass thermal fuse on the rear face of the magnetron assembly; many steel spanners became attached to the magnet. Otherwise it was a pretty neat transmitter.

Neatishead in 1977

The T84 had turntable change during the Christmas period and the S259 was bought in for cover. There were some very strong winds which caused one of the S259 tents to become detached from its guys, wrap itself around the S259 antenna and tip the container over. Some types of story keep happening!