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Foreword

We take this opportunity of extending our welcome to you on your visit to Royal Air Force Sopley. Whilst here, we have basically four separate but complimentary sections to show you. These are:-

        a.    The Military Area Radar Air Traffic Control Operations Room, which includes the co-ordination/allocation section.

        b.    The Special Tasks Cabin.

        c.    The Ministry of Aviation Radar Section within the Military Operations Room.

        d.    The Joint Air Traffic Control Area Radar School.

To you, the aircrew who visit us, we have aids to offer should you wish to avail yourselves of them, and to those perhaps less active in the flying business, we trust we shall also have something to arouse your interest. If we can give you an assurance that a genuine effort is being made to safeguard aircrew and passengers whilst in the air, then we shall be satisfied. Below is a rather non-detailed diagram of the technical block, which might help you to orientate yourself, but should you not be escorted and happen to get confused or lost, please do not hesitate to ask anyone for guidance. We trust that you will consider your visit worthwhile for, rest assured, we are very happy to have you with us.

J H T Pickering, Wing Commander, Officer Commanding, Royal Air Force Sopley.

 

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History of Royal Air Force Sopley (see also the other RAF Sopley page on this site)

Royal Air Force Sopley during the last war (1939-45 -Ed) was an active Ground Controlled Intercept (GCI) station, under the operational control of Fighter Command in the defence of Great Britain. In 1959 the role of the unit was changed to include the School of Fighter Control plus a Special Tasks Cabin, to look after both the military and civil research and development requirements and also to afford control facilities for fighter interception practice for Royal Air Force Chivenor.

With the advent of more and much faster aircraft - both military and civil - combined with the growth and complexity of the airways network over the United Kingdom, it was decided by the Royal Air Force, in the interests of air safety, to explore the possibility of using radar to afford positive control of military aircraft crossing airways. Trials were carried out successfully and, in October 1959, the Air Traffic Control Area Radar system was introduced at Sopley.

The School of Fighter Control was later disbanded and the station (including the Special Tasks Cabin) then became part of the United Kingdom Air Traffic Services organisation, which is known today as Military Air Traffic Operations (now [2002] part of Royal Air Force Strike Command). Initially the existing Air Traffic Operations Room at Sopley was equipped with only four radar consoles, but over the years its capability has been increased by the addition of more consoles and height finders, in an attempt to meet the ever growing requirement.

In October 1960 and additional unit, known as the Joint Air Traffic Control Area Radar School , was established at the station, and this continues to function today.

(for more on air defence and air traffic control radar sites we recommend the radarpages website)

Radar Equipments

Type 80 A 10 cm radar with an approximate range of 200 nm at 40,000 feet. It is the main or basic equipment and is especially useful for the middle air and upper air tasks. The definition, resolution and afterglow is first class, but being 10 cm it is unfortunately very susceptible to weather effects.
Type 7 A metric radar used primarily as a standby for the Type 80 in the medium/high height bands. It is not generally affected by weather and thus can be of great assistance when the Type 80 is. However it has a limited range of approximately 100 nm at 40,000 feet, and a rather large sausage shaped response which tends to limit its usefulness.
Type 14 A 10 cms radar used as a standby to the Type 80 in the low/medium height bands for aircraft flying from within 25 to 120 miles for the station. Once again, being 10 cm, this equipment is susceptible to weather conditions.
Type 13 A height finding radar equipment of which we have five. It is 10 cm, scanning through 360 degrees and nodding through 20 degrees. It indicates heights on the aircraft selected but owing to its inherent inaccuracies, it is only used to establish comparative heights between two or more selected aircraft. Its range is approximately 100 nm.

Radar Console Data

The are nine 12" radar consoles (plan position indicators - PPI) in use by the Air Traffic operations Room. Seven of these are used by military controllers and the other two by controllers from the Ministry of Aviation. In addition to these nine consoles, there is also a pedestal type 21" console used for co-ordination. The Special Task Cabin is equipped with two 12" consoles and one pedestal type 21".

On each PPI display you will notice a rotating line of light, the centre of which is the position of the station or aerial head. One of four scales of an area to fill the tube face can be selected, e.g., 80, 160, 240 or 320 nm. Coupled with each scale is a video map which is an electronic outline of the coast within the area selected, plus other prominent features such as airways etc. Superimposed electronically over the video map display is a Georef grid system map. The latter is used to assist the controller in the geographical positioning and location of aircraft, airfields, towns, etc.

When centrimetric radar is being used, the aircraft responses show on the tube face as small pin heads of light, but when metric radar is used these responses appear as elongated sausage shaped form of light, much bigger than the former. Storms or heavy rain appear on the tube face as smudges of light, varying in intensity according to their severity, and widespread heavy snow or rain can cause considerable difficulty by blanking out parts of the tube, thus making it extremely hard if not impossible, for the operator to see aircraft returns. It is also possible to have interference from other radars on the same or similar frequency, and these appear on the tune face as radial lines of light and in other forms which appear to tend to confuse the picture.

IFF/SIF

An electronic facility is incorporated in each console to assist in the identification of aircraft. Most modern aircraft have secondary radar installed in the form of an Identification Friend of Foe (IFF) or Selective Identification feature (SIF). When the aircraft's secondary radar is selected to the pre-determined coding, the resulting energy is picked up by the ground station. If the controller has selected the compatible interrogation switch on his console, a series of slashes beyond the normal aircraft response will appear on his display. Thus, by a system of allocation of slashes or permutations of slashes to different categories of aircraft  and ground station, it is possible for the station to identify the aircraft so fitted. In fact under certain circumstances, when the aircraft and ground station are both equipped with SIF, it is actually possible to identify a particular aircraft. (It is a fairly complicated issue to explain in brief, but the controller in situ at the PPIs will explain it to you in detail)

Communications

Sopley call sign - Southern Radar

The air to ground and ground to air communications consist of eight UHF channels and eleven VHF. Of these three in each band are continuously monitored by a listening watch. The selection of frequencies on which listening watchs are to be kept is decided in the light of their importance, which may from time to time be reviewed.

The landline network is fairly comprehensive, and apart from the usual operational and administrative PBXs, each controller is able from his console to contact directly nine external agencies to facilitate handover/takeover of aircraft, emergency action, and selected airfields. he is also in direct contact with a further twenty-four positions within the operations block - for example, with all other consoles and the co-ordination section, etc. The Signals Traffic Unit handles all incoming and outgoing operational teleprinter messages, and this section is manned twenty-four hours  a day. Tape recordings are used to record (for subsequent play back when necessary) the two-way spoken word over the RT and telephones. Further , there is a device known as a photographic display unit which photographs and records on film a picture of the radar display every fifteen seconds.

Military and civil integration

The Air Traffic Control Radar Units have been introduced to provide air traffic control facilities to aircraft flying within their areas of responsibility, and are manned and equipped jointly by Ministry of Defence (Air) and the Ministry of Aviation.   Sopley is jointly manned by military and civil controllers. Military aircraft can be provided with control facilities on request both inside and outside controlled airspace. The civil control positions are used to assist and supplement the Southern Air Traffic Control Centre at Heathrow, London Airport, during the control of aircraft along Green (Green 1 -Ed) Airway. They also control aircraft in Amber 25 Airway which runs from Liverpool to Exeter routing to the Channel and Scilly Isles. It is of paramount importance that military and civil aviation have equal rights in time of peace, and to avoid duplication of effort, military and civil aircraft must share, so far as possible, the ground organisation and aeronautical facilities.

In the case of Sopley, the civil element is located right in the Operations Room with the military, both using the same radar information, identical PPIs and sharing common information displays. The question of a harmonious and understanding liaison between military and civil air traffic agencies is indeed a realistic and important one, and although the co-ordination that exists is extremely close, we continue to strive for perfection.

Area of responsibility

The extent of the controlled airspace over the United Kingdom in relation to civil airways is depicted by the diagram below.

 

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The picture below shows the areas of responsibility of the various ATC Area Radar stations covering the UK and its approaches. Sopley's specific area is marked by shading.

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Servicing

All radar and ground to air communications are serviced by Airwork Services Ltd., and not by the Royal Air Force. A resident manager is located on the unit. This method of servicing by civilian contract has proved commendable.

Military services provided

The Air Traffic Control Radar Units, of which Sopley is one, use ground operated radar for the safe and expeditious handling of aircraft making both transit flights and approaches into RAF airfields. For aircraft in transit in the high and medium height bands we can provide positive control or survellance to guard against the risk of collision. Control on request is given to aircraft when in controlled airspace, in particular airways, terminal areas etc., to ensure compliance with the separation standards from civil airline traffic. We can also give aircraft navigational assistance, and are in a position to aid the emergency organisation in the recovery of distressed aircraft.

The main advantages of this type of radar service may be summarised as follows:-

    a.    No special equipment is required in the aircraft.

    b.    Pilots require no special training.

    c.    Any type of aircraft with radio telephony can be handled.

    d.    The aircraft position is known, and a high degree of protection against collision can be given.

    e.    Many aircraft can be handled at once.

Like the other Radar units, Sopley's tasks are many and varied. primarily we deal with upper space traffic, i.e. above Flight Level 250 (25,000 feet). This consists in the main of "V" bombers, and American operational and training flights into and out of the United Kingdom. In addition we position Transport Command passenger carrying aircraft at Lyneham from their overseas trunk routes. There is also a requirement to position American aircraft from overseas, i.e. Spain, the United States, etc., at the receiving airfields in the Oxford area.

Sopley is manned 24 hours each day and every day, by controllers and staff, to ensure as far as possible that a radar service is available whenever required. A brief description of the various services which are, on request, provided for military aircraft are outlined below.

Services

Airways Crossings for Military Aircraft

When requested, these are effected under positive radar control to ensure a minimum separation of 5 nm from airways traffic. Heathrow (London) and Yeovilton radars are frequently used in conjunction. At all times close liaison is maintained with the MOA controllers. Bearing in mind that the upper limit of the airways is 25,000 feet, statistics show that with the advent of higher flying military jet aircraft the numbers of airways crossings are considerably reduced from those of earlier years.

Upper Air Space Control for Military and Civil Aircraft.

This service is available to aircraft flying above Flight Level 250 (25,000 feet), civil aircraft being handled by the MOA controller and military aircraft of the Royal Air Force. Radar Control, Surveillance or Limited Service as defined in the FLIP and En Route documents is offered to conform to the separation standards laid down by HQ MATO and/or MOA, thereby providing an anti-collision service against both identified and unidentified traffic along any desired route or flight pattern.

Transit Surveillance/Control of Military Aircraft

This service is available to aircraft flying at or below Flight Level 250 within Sopley's area of responsibility and radar coverage. Altimeter settings for regions and weather reports for individual airfields of destination are also provided on request.

Extended Approaches to Selected Airfields

These are carried out (on request) mainly to the following stations:

Midlands USAF bases Upper Heyford, Brize Norton
RAF Bases Lyneham, Colerne, Wroughton and Thorney island (these last two only on rare occasions).
RAF Gaydon only when Mersey radar is inoperative

Approach procedures to these airfields have been approved by MATO. In addition, USAF procedures are listed in the appropriate American flight publications. Currently trials are being carried out by Sopley (Southern Radar) to provide all the USAF proceeding to the Midlands bases with a  radar or procedural service.

Assistance to ATCC Uxbridge in the Handling of Emergencies

The Radar and Radio facilities of the unit are continuously available (on request) to the Centre Controller handling emergency incidents. Whilst all possible assistance is readily available to ATCC Uxbridge, the overall responsibility at present remains with the centre controller for the satisfactory resolution of the emergency.

Navigational Assistance

In conjunction with the other services provided, navigation assistance is available to aircraft when requested. This is always given when prohibited or restricted areas lie in the path of an aircraft.

Special Commitments

Radar Services are also (to a fairly limited degree) provided for tasks such as calibration flights, flight refuelling, sonic runs, command trials and research and development flights.

It can be seen from the forgoing that the tasks in hand at any one time could be many and varied.

Co-ordination and Allocation

This section is manned by an Officer and a team of NCOs and airmen, the former being responsible for allocating the various tasks undertaken by the controllers in the operations room to ensure an even distribution of the workload. Further, in the interests of aircraft safety, all the traffic being handled by the operations room and the special task cabin at any given time is tracked and co-ordinated on a large 21" radar console where conflictions may be observed and then notified to the relevant individual controllers for avoiding action. Primary radio frequencies are continuously monitored and all R/T and telephone communications of an Operational nature are tape recorded. In addition, the main radar picture is filmed for future reference if and when required.

Analysis of aircraft handled

The following figures indicate how, over a period of years, more and more aircrew are requesting radar services from Southern Radar.

1961 35,570
1962 49,016
1963 52,951

Special Tasks Cabin (Research and Development)

Services

It is known to the users as "Cabin Four" and this unit is manned by Fighter Controllers. It handles fighter interception practices from Chivenor and is responsible for affording services to civil and military aircraft engaged on research   and development flying from such bases as Farnborough, Boscombe Down, Dunsfold, Wisley, etc.

Workload

The dependence placed on Southern Radar by the world of Research and Development is revealed in the 1963 task figures which show that 5,000 hours were spent controlling 2,100 individual movements in Cabin Four.

Co-ordination

Cabin Four tasks are notified to the main operations room co-ordination console, tracked and co-ordinated with other traffic

Task Characteristics

Apart from the straightforward practice interceptions the Cabin carries out with aircraft from Chivenor, a great deal of the controllers' work is in the Research and Development field, which is particularly exacting. These sorties are usually scheduled to fly precise profiles and the aircraft are normally loaded with the telemetry equipment. It is therefore obvious that the pilots do not take kindly to indiscriminate changes of heading or flight level, or indeed, any excessive R/T chatter. Thus a Cabin Four controller has to know exactly hat he is going to do, and to do it with a minimum of instruction to the aircraft. This type of interception work is made even more difficult by the fact that the controllers are working in an Air Traffic Control environment and governed by ATC rules.

Ministry of Aviation participation

Services

The Ministry of Aviation Unit at Sopley has been engaged since March 1961 in providing a radar service within an area from the Greenwich Meridian west(wards) to 7 degrees West, and from 5230North south(wards) to 4940N. Within this area, on an operational trials basis, radar service has been given to aircraft operating on Upper Air Routes and Advisory Routes. During the three years that the MOA Radar Unit has been in operation, civil traffic has steadily increased, and a considerable volume of civil upper air traffic is now handled daily. the peak periods are between 0600 and 0800 when the main flow of eastbound transtlantic traffic enters the United Kingdom FIR from Ireland, and again at midday and early afternoon when the majority of the westbound transatlantic traffic departs from, or overflies, London. In addition to the above, the Sopley MOA controllers are also able to provide valuable assistance to London airways by applying radar control to Airways traffic that is beyond London's Radar cover, effecting climbs and descents as necessary under the direction of the sector procedural controller. This expedites the flow of air traffic by reducing the requirement for full procedural separation standards.

Co-ordination

In support of these functions the MOA Radar Unit co-ordinates closely with Sopley military radar controllers, exchanging information on identified civil and military traffic, to ensure the latter's safety and to reduce avoiding action to a minimum. This co-ordination also embraces R&D aircraft under the control of the Special Tasks Cabin at Sopley, and the fact that in 3 years relatively few civil aircraft have been given avoiding action against such R&D traffic is a measure of the degree of co-ordination and co-operation that exists between radar controllers at Sopley.

Manning

Staff problems have precluded a 24 hour service being provided to date, but it is hoped to resolve the problem in the near future, coincident with the introduction of a separate frequency for the control of civil traffic above Flight level 250.

The Joint Air Traffic Control Area Radar School

The School was opened in October 1960 to train Royal Air Force, Royal Navy and Ministry of Aviation Air Traffic Controllers to a common standard in the operation of long range radar for Air Traffic Control Purposes. The course is of 6 weeks duration and normally consists of fourteen prospective Area Radar controllers. Whilst the course is designed to train qualified Air Traffic Controllers to perform area radar duties, and is therefore of a practical nature, rules and procedures have to be covered in order to create a foundation of mutual understanding between the Controllers from the different services, who are required to work in ever increasing harmony and co-operation.

Most of the practical training is carried out by using synthetic radar responses superimposed on a synthetic, filmed or live radar background, according to the stage of advancement of the course. During the final two weeks, a limited period of time is spent with each student, under supervision, controlling military aircraft (live) from the operations room of Royal Air Force Sopley. Each student is given a minimum of fifty hours actual controlling under instruction during the 6 weeks course, in which the following aspects of Area Radar are covered:-

        a.      Control/Surveillance of Aircraft outside Controlled Airspace.

        b.     Control/Surveillance of Aircraft within Controlled Airspace

        c.     Control/Surveillance of Aircraft in the Upper Airspace.

As at March 1964, attendance at the School has been:-

Royal Navy 36
Royal Air Force 130
Ministry of Aviation 126
Overseas Governments 8
Total 300