ROTOR

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Entrance bungalow to former ROTOR station at Kelvedon Hatch

ROTOR was a huge and elaborate air defence radar system built by the British Government in the early 1950s to counter possible attack by Soviet bombers. The system was built up primarily of war-era radar systems, and was used only briefly before being eventually replaced by the more modern Linesman/Mediator system. A similar expedient system in the United States was the Lashup Radar Network.

Post-war situation[edit]

UK radar operations were wound down late in the war, and by the time the war ended were already largely unused. It was assumed that another war was at least ten years away, and the need for any improvements in the cobbled-together system seemed remote.

Thinking changed dramatically in 1949 with the Soviet test of their first atom bomb. It was known that the Soviets had made exact copies of the B-29 Superfortress as the Tu-4 Bull, and these aircraft had the performance needed to reach the UK with a nuclear payload. Studying the problem, the 1949 Cherry Report suggested that the 170 existing Royal Air Force radar stations be reduced to 66 sites and the electronics extensively upgraded.

Most of the new network would be made up of 28 re-built Chain Home systems, while the rest were taken from the existing selection of Chain Home Low, Chain Home Extra Low and the various Ground-controlled interception (GCI) radars that had formerly served special purposes. This was, in part, a stop-gap measure anticipating the availability of the dramatically improved Type 80 Green Garlic radar which would replace the various early warning radars with a single system of much greater performance. Interception guidance would still be handled by existing systems in either case.

All of the radars were to be improved in terms of siting with the addition of hardened control bunkers to protect the operators from a conventional attack. On the east coast, the coast toward which a Soviet attack would be most likely, the bunkers were underground in the 'R' series (R1, R2, R3 and R4 etc.), while those on the western side of the UK were generally semi-sunken hardened structures ('R6') or above ground 'Secco' type huts (Hartland Point etc.). The R-series bunkers themselves were otherwise similar, featuring 10-foot-thick (3.0 m) concrete walls with all equipment, operations generators and air conditioning located inside.

Additionally, ROTOR re-arranged the existing RAF Fighter Command structure into six "Sector Operational Commands" (SOC) with their own command bunkers (three level 'R4' protected accommodation). Only four of these were built. Additional "Anti-Aircraft Operations Rooms" were built to coordinate the British Army's AA defences in the same overall system. The entire network of bunkers, radars, fighter control and command centres used up 350,000 tons of concrete, 20,000 tons of steel and thousands of miles of telephone and telex connections.

The work was mainly carried out by the Marconi Wireless and Telegraph Company in several phases, called ROTOR 1, ROTOR 2 and ROTOR 3.

Post-ROTOR[edit]

As the anticipated Type 80 "Green Garlic" radar started testing shortly after ROTOR came online, it became clear that it could fill both early warning and interception guidance from a single site. This dramatically decreased the complexity of the ROTOR system, which otherwise required sightings from the early warning radars to be telephoned to the fighter control GCI stations for local plotting. By concentrating all of this complexity at a single site the total number of operators was greatly reduced.

As a result of the introduction of the Type 80 (Green Garlic), many of the existing ROTOR sites were rationalized into Master Radar Stations (MRS), while the rest were made redundant, some only two years after opening, and all of the AAOR sites were closed. A few of these were re-used for government department ('RSG's) and local authority wartime headquarters. In the mid-1960s the MRS's themselves were replaced with a new system called Linesman/Mediator.

Until the end of the Cold War many of the sites were retained by the government but now have been sold off to private buyers or converted into museums (for example 'RAF Hack Green') and some transferred to the National Air Traffic Control Centre.

Sector Operation Control centres[edit]

Custom Built:

World War II:

List of ROTOR Sites[edit]

Site Name Site Designator Grid Reference Site Purpose
Aird Uig WIU NB 047390 R10 CEW Type 80
Anstruther NO 568808 R3 Type 80
Barnton Quarry MHA NT 203748 R4 SOC Caledonian
Bawburgh WRK TG 165080 R4 SOC Eastern, SRHQ4.1, RGHQ4.1
Bawdsey PKD TM 347388 R3 GCI(E)
Beachy Head HEB TV 590959 R1 CEW Type 80
Bempton RMF TA 192736 R1 CEW
Boulmer EZS NU 240125 R3 GCI Type 80
Box ST 850690 SOC Southern
Buchan GBU NK 113408 R3 GCI Type 80
Calvo NY 144545 R8 GCI
Charmy Down ST 768702 R8 GCI
Chenies HAM TQ 015997 R8 GCI
Cold Hesledon IDW NZ 417468 R1 CEW / CHEL
Comberton SO 968461 R8 GCI
Crosslaw HCV NT 880680 R2 CHEL
Danby Beacon NZ 732097 CH
Douglas Wood NO 488415 CH
Drone Hill NT 845665 CH
Drytree SW 732218 CH
Dunkirk TDE TR 076595 CH Type 80
Fairlight GWB TQ 862113 R2 CHEL(A)
Faraid Head RAI NC 389714 R10 CEW Type 80
Folly SM 858195 CH
Foreness TR 385710 CHEL
Gailes FUL NS 327361 R8 GCI type 80
Goldsborough JEX NZ 830138 R2 CHEL(A)
Hack Green HAK SJ 647483 R6 RGHQ
Hartland Point HAT SS 237277 R8 GCI
Hayscastle Cross CHX SM 920256 CH Type 80
High Street TM 411720 CH
Hill Head NJ 947616 CH
Holmpton VQJ TA 367225 R3 GCI(B) Type 80
Hope Cove HOP SX 716374 R6
Hopton TOH TM 540990 R2 CHEL(B)
Inverbervie LGZ NO 841734 R1 CEW
Kelvedon Hatch XSL TQ 561995 R4 SOC Metropolitan
Kilchiaran ECK NR 207616 R11 CHEL
Langtoft LAT TF 155129 R6 GCI Type 80
Longley Lane LOA SD 541365 SOC Western
Neatishead TG 346184 R3 GCI SOC
Netherbutton BNT HY 464045 CH
Pevensey TQ 644073 CH
Poling TQ 043052 CH
Portland NIB SY 696735 R1 CEW
Prestatyn SYP SJ 079819 R11 CHEL
Ringstead SY 751817 CH
Rye TQ 968232 CH
Sandwich YTM TR 303574 R3 GCI Type 80
Saxa Vord AXA HP 629165 R10 CEW Type 80
Scarinish FLY NM 032456 R8 GCI Type 80
School Hill HSL NO 908982 CH
Seaton Snook DYR NZ 519280 R3 GCI Type 80
Sennen SW 376246 CH
Shipton KFY SE 542618 R4 SOC Northern
Skendleby TF 438709 R3 GCI
Snaefell MOI SC 397869 R11 CHEL
Sopley AVO SZ 163977 R3 GCI type 80
St Annes SD 348303 R8 GCI
St Margarets AGC TR 370451 R1
St Twynnells TWY SR 944976 R6 GCI Type 80
Staxton Wold TA 023778
Stenigot TF 256827 CH
Stoke Holy Cross TG 257028 CH
Swingate TR 335429 CH
Trelanvean SW 762193 CH
Treleaver SW 766174 R6 GCI(B) Type 80
Trerew RTW SW 812585 CH
Trewan Sands TES SH 322754 R8 GCI
Trimingham QLE TG 290385 R1 CEW Type 80 CHEL
Truleigh Hill TQ 224109 R2 CHEL
Ventnor OJC SZ 565784 CH, R1 CEW, type 80
Wartling ZUN TQ 662088 R3 GCI type 80
West Beckham TG 142389 CH
West Myne ZEM SS 928486 R11 CHEL
West Prawle SX 771374 CH
Wick IKA ND 326537 R8 GCI

Sector Operations Centres[edit]

From Sub Brit website

  • Caledonian Sector: R4 SOC at Barnton Quarry
  • Northern Sector: R4 SOC at Shipton
  • Eastern Sector: R4 SOC at Bawburgh
  • Metropolitan Sector: R4 SOC at Kelvedon Hatch
  • Southern Sector: SOC at Box
  • Western Sector: SOC at Langley Lane

ROTOR Radar Sites[edit]

This links to modern aerial site photographs [1] of both 'retained' Chain Home & ROTOR sites. Note there now may be nothing visible of the original site on the ground and only crop marks visible from the air.

RAF Staxton Wold is the only Chain Home site still used as a military radar site but with no remains of the CH station on site after being rebuilt for Linesman / Mediator in 1964.

Note: A number of ROTOR sites had very short operational lives, sometimes less than 1 year and thus don't appear on many maps. Example: West Myne [2] in Somerset was the last ROTOR 3 CHEL site. It was completed / tested in 1957 after the introduction of the T80 radar and after many ROTOR stations had already closed. The site was within Exmoor National Park and its creation was strenuously opposed by the National Trust who lost no time in obliterating the site immediately after closure.

List of ROTOR SITES.

  • Aird Uig
  • Anstruther
  • Bawdsey
  • Bempton
  • Beachy Head
  • Boulmer
  • Buchan
  • Chenies
  • Cold Hesleden
  • Crosslaw
  • Fairlight
  • Faraid Head
  • Foreness
  • Gailes
  • Goldsborough
  • Hack Green
  • Hartland Point
  • Hope Cove
  • Hopton
  • Inverbervie
  • Kilchiaran
  • Killard Point
  • Langtoft
  • Neatishead
  • Partrington
  • Prestatyn
  • Portland
  • Sandwich
  • Saxa Vord
  • Scarinish
  • Seaton Snook
  • Skendleby
  • Sopley
  • St Annes
  • St Margaret's Bay
  • St Twynnells
  • Treleaver
  • Trimmingham
  • Truleigh Hill
  • Ventnor
  • Wartling
  • Wick

See also[edit]

References[edit]

Further reading[edit]

External links[edit]