History of the ADMIRALTY RESEARCH LABORATORY (ARL) Teddington: 1921 to 1977

Official crest of ARL

ARL main building from 1939 - known as 'Fire Control'

Official crest of ARL

More information on:  ARL Upper LodgeARL Underwater CCTVARL CORSAIR programme: AES Perranporth; AMPS Portballintrae: AES Unst;  Location of ARL & Upper Lodge;  ARL Remains & Monuments;  Contact for comment and information requests

Relevance of the work

The greater proportion of modern naval warfare technology stems from the research conducted by the staff of the Admiralty  Research Laboratory, Teddington over the period 1921 to 1977. For example, some of this research enabled major advances in submarine stealth, weapons and sonar, including streamlining, machinery noise reduction, faster and quieter Pump-Jet propulsion, and Towed Array long-range passive sonar.

What happened to ARL

In 1977-8 the majority of the underwater acoustics work was transferred to Portland, Dorset. This move came in the wake of a renaming of the establishment to "Admiralty Marine Technology Establishment (ARL)". The main site in Queens Road was closed down in 1988 and by then what was formerly ARL was simply: Admiralty Research Establishment (ARE) Teddington. With the formation (in 1991) of the tri-services Defence Research Agency, the remaining former ARL site at Upper Lodge became DRA Teddington, only to be closed on Christmas Eve 1993 bringing to a complete end 72 years of ground-breaking scientific research that was of immense benefit to the Royal Navy.

Photo: At midday on 23rd Dec 1994 Pipe Major John Haynes (77th Highlanders), RN Piping Society, and former Site Manager piped the last staff from Upper Lodge. Site Manager Brian Moses and Head Patrolman George Bullen locked the gates.
For the record, John piped "The Lament For The Dead".

The fact that there is now little trace that ARL ever existed should not belittle the essential contribution made by the staff at ARL to the Royal Navy's capability and performance throughout the Cold War.

ARL locations and remains

Declassification of the work

Such was the highly classified nature of the work outlined in these web-pages that practically nothing was generally known until the latter-day release of Admiralty documents under the Freedom of Information Act 2000; notably the 30 year rule. Currently (2015) there are 5000-odd documents available from The National Archives at Kew, relating to ARL; principle references are: ADM212 – Correspondence and Letters, and ADM204 - Reports and Notes. It is important to note that a fair proportion of the work was never written-up, and that some aspects of the work still remain classified and the reports not released to the public.

Other facts

The sites were on Crown-owned land and maintained by a local department of the Ministry of Public Building & Works (MPBW) based in Queens Road, which was a facility originally established for the NPL and shared. This was the only thing that ARL and NPL had in common, as they were totally separate establishments controlled by different Government bodies. Further ARL was what was termed a "Class A" establishment i.e. a high security site with restricted and controlled access of non-ARL personnel. However, ARL staff had full access to NPL's canteen and sports ground. Lunchtime access to NPL's canteen was via a guarded door in ARL's high (broken-glass topped) boundary wall next to a pair of large wrought-iron ornamental gates. These gates were normally locked but opened morning and evening for staff to enter and leave via Bushy Park.


Admiralty Research Laboratory
Queens Road
TW11 0LN


Teddington Lock (01-977)  3231

All correspondence was handled by the Registry in the "Fire Control" building at Queens Road, irrespective of whether the addressee was based at Queens Road or Upper Lodge.

Some of ARL L-Group staff outside the main entrance of the 'Fire Control' building (officially known as Centre Block), which faced Bushy Park.

This website

In 2005, armed with knowledge acquired as a member of ARL’s 'Submarine Detection', and 'Noise Measurement & Analysis' Groups over the period 1963-73, I started documenting the achievements of ARL staff, primarily so that they may have the recognition they so rightly deserve.

Since first creating an ARL website, a significant amount of additional information has been gathered, which has led to a major revision and a huge increase in its size. So, welcome to my bigger & better ARL website!

Nigel RD Godsell - Contact me

Still to be covered:-

Solid state physics – centimetric wave-guide materials.
Autolycus – non-acoustic detection.
Human Factors – watch-keepers efficiency improvements; rationalisation of ship machinery control consoles; sonar operator’s task analysis; sonar operating & optimisation aids.
ARL Groups - description

Screen size appears here

Website version: Jun 2015
Please use the 'contact' link to report difficulties and problems.

This is a provisional version of the upgraded website with the Upper Lodge webpage incomplete.

These ARL webpages are formatted for display with a resolution of 1024 x 768 pixels minimum. Further, they were developed using MSIE 11, although earlier versions e.g. MSIE 8 has no problems other than blocking Active X, which can be allowed in complete safety for these webpages; they use some very basic Javascript that is mistakenly determined as Active X, by MSIE 8.

In fact, viewing with MSIE is strongly recommended on basis of the far superior quality of the text characters. Personally I'm happy to wait the odd few milliseconds more and have text I can read effortlessly, than use the likes of Google Chrome and Firefox, and struggle with their (faster to render) pixel-starved character sets.


Overview of the work

The Admiralty Research Laboratory (ARL) was established in 1921 in response to the Board of the Admiralty aspirations to expand upon the technological advances in naval warfare made during the First World War; occupying the eastern end of Queens Road in Teddington, it was well placed to take advantage of the standardisation and testing facilities developed by staff, next-door, at the National Physical Laboratory (NPL).

Original entrance to ARL some 75ft west of the later entrance constructed when the 'Fire Control' building was built, in 1939. According to A.B.Wood, the 1921 Queens Road entrance was only used by VIPs; staff used
the rear entrance accessible from within NPL site.

ARL’s remit as the centre for Royal Naval science was first to determine, and then develop expertise in, the underlying science of virtually all aspects of Royal Navy operations, and subsequently master the many processes involved in ensuring that science is applied effectively.

In the early years, ARL forged strong and lasting links with the Admiralty Experimental Works (AEW) at Haslar, Hants, and the Admiralty Engineering Laboratory (AEL) at West Drayton, Middx. Rapid progress was made as ARL developed the capability of constructing bespoke test and measurement equipment for themselves. Generally, the specially-made equipment supported the process of problem solving by identifying the nature and cause of the problem, as a prelude to ARL evolving a practical solution.

Some of these specialised pieces of equipment provided general improvements in ship and submarine operations e.g. ARL’s design and development of Navigational Plotting Tables (the earliest form of course plotter being trialled in the battleship HMS Hood in 1925), and Depth Echo Sounders for safe navigation and survey. The latter stemming from ARL’s increased understanding of underwater sound as applied to ASDIC, as Sonar was then known in the UK. ARL literally turned a suck it and see black art into the science of underwater acoustics. Comparable strides were being made into the dynamics of the motion and behaviour of bodies in water with respect to warships, submarines and torpedoes.

Between the World Wars

A key aspect (continually) addressed, over the years, was the detection of submerged submarines by use of underwater sound. The first technique selected was Echo Detection, which involves transmitting a high-power sound pulse and then listening for the echo reflecting off the target. By 1927 ARL Acoustics Group’s work on Echo Detection ASDIC (active sonar) was considered sufficiently mature that it was transferred to HMS Osprey at Portland, Dorset, for the development of service equipment. This opened the way for study of the more fundamental issues, which transpired to be in favour of the submarine instead of against it. As was ARL’s research on large capacity Lead-Acid batteries for submarines that was sufficiently advanced by 1931 for the work to be carried through to conclusion by AEL.

One area of ARL research that would prove to be highly beneficial was the study of the noise radiated by vessels. Whilst the Acoustics Group undertook the detailed measurement and analysis of self (radiated) noise, the Fluid Dynamics Group concentrated on the dynamics of the motion and behaviour of warships, submarines and torpedoes, through water in terms of their shape, control and propulsion, with the aim of increasing efficiency and reducing the acoustic noise generated.

Even before the outbreak of World War Two the Acoustics Group at ARL had embarked upon a study of the in-water sound made by the machinery of submarines, with the aim of reducing the radiated noise thereby making Royal Navy submarines far more difficult to detect. Another important advantage of (self) noise reduction was the beneficial effect on sonars fitted to submarines; it meant there was less background sound (when passively listening) to mask the reception of the noise made by target ships and submarines, or the (transmitted) sound reflected by them i.e. their echo.

World War Two

The greater proportion of ARL’s contribution during WWII was in terms of consultancy to other establishments on the design and effectiveness of countermeasures to German submarines, sea-mines and torpedoes; ARL’s individual contributions were the ‘Publican’ decoy for the German acoustic homing torpedo codenamed ‘Gnat’, and the system of degaussing vessels as a measure of protection against German magnetically-actuated sea-mines.

ARL made considerable developments in optics and infra-red for gunnery fire control and naval covert operations. The ARL Optics Group developed the concept of ‘Telephotography’, the use of TV for the transmission of photographs from aircraft to ship and shore. ARL’s Fire Control Group (boosted by a group moved from Greenwich to ARL, working on gyros) developed a concept of stabilised platforms successfully used for torpedo depth and direction control, searchlights, gun directors and guns. Such was the expansion of work and success in these areas that the Fire Control Group became the Admiralty Gunnery Establishment (AGE) in 1943, initially co-located with ARL at Queens Road it moved to Portland, Dorset in 1953.

Throughout WWII, ARL made great advances in vessel noise reduction having established its first Noise Range at Loch Goil, Argyll, Scotland in 1942. In the case of the X-Craft midget submarines their main machinery was mounted on a raft attached to the hull by resilient mountings designed by ARL. The consequent reduction in noise resulted in the range at which they could be detected falling from 10,000 to 200 yards.

A somewhat unlikely contribution, and an indication of the breadth of ARL’s research, is the Wave Group (formed 1944) work to predict the sea conditions for the Normandy Landings. Similar to the formation of AGE, ARL’s Wave Group was renamed the National Institute of Oceanography in 1949 and moved to its own establishment near Wormley, Surrey in 1955.

Post World War Two

With the cessation of hostilities in Europe in 1945, a few of the GC&CS Bletchley Park mathematicians and statisticians spent periods of time at ARL, the most notable being Dr I.J. (Jack) Good (1959-62 at ARL) who together with Professor Donald Mitchie (the Artificial Intelligence pioneer) was responsible for the final form of the Colossus computer (Colossus II), when at Bletchley Park. A realisation was made, early on, that Numerical or Statistical Analysis had a part to play in furthering understanding of operational issues relating to sonar and the host platforms. Another mathematician, and acquaintance of Bletchley Park's most famous cryptanalyst Dr Alan M. Turing, Dr Alister G.D. Watson became head of the Submarine Sonar Research Group at ARL. In 1945 both of them were working in Teddington, 200-300 yards apart, although in different establishments as Alan Turing had joined the National Physical Laboratory (NPL) to design and develop the pioneer, programmable computer: Automatic Computing Engine (ACE).

In 1951, although submarine related work (principally their quietening, detectability & detection) was absorbing considerable resources, ARL was more than capable of responding to urgent needs. For instance, at the time of the tragic loss of HM Submarine AFFRAY, ARL scientist W. Rosse Stamp hastily designed and constructed a submersible enclosure for the camera of a Closed Circuit Television (CCTV) system. The equipment (the world’s first rapidly-deployable (portable) underwater viewing system) was embarked upon HMS RECLAIM and operated, by Rosse and Lionel ‘Buster' Crabb, without a single hitch, and ultimately made the initial identification of HMS/M AFFRAY at her final resting place. The system continued to provide great assistance to the diving operations during the lengthy investigation of the sunken submarine. More information of ARL's underwater CCTV.

Note Rosse Stamp was one of a number of staff from the Admiralty Photographic and Instrumentation Research Laboratory (known as April), Kensington, London that were accommodated at (newly acquired) Upper Lodge when it was absorbed into ARL in 1949. As a commercial diver for hire (at that point in time), Cdr Lionel Crabb assisted April with their work on underwater photography and cine-photography, and visited Upper Lodge when April became the Instrumentation (K) Group of ARL.

Such was the utility of the portable underwater viewing systems that it opened-up a whole new area of research at ARL. As a consequence, in January 1954, at the time of the de Havilland Comet G-ALYP (Yoke Peter) crash in the Tyrrhenian sea off the Island of Elba, ARL was once again called upon to provide underwater viewing equipment to aid the search; ARL's George Macneice was flown out and operated the system to great effect, embarked upon RFA SEA SALVOR.

Cold War

Undoubtedly the Cold War period was the busiest and most productive time for ARL. The nuclear age meant involvement in radiological defence. ARL staff developed a high level of expertise and were widely consulted following fruitful research and design of dockyard, ship and crew decontamination techniques that included spraying ships with seawater, and a bar of decontamination soap. The research also led to the development of radiation detectors and monitors for ships, and Film Badges and pocket dosimeters for sailors.

The work on ship, submarine and torpedo hydrodynamics undertaken by ARL’s Fluid Dynamics Group demanded better facilities, which were constructed on the Upper Lodge site following its acquisition by ARL in 1945. The successful use of a small-scale Rotating Beam Channel (RBC) and a 12” working section Water Tunnel for studying and developing the theory of the water flow around bodies and propulsors, led to larger versions of both (ten times larger RBC & 30” Water Tunnel) being constructed on the site and operational by the mid-1950s.

New hydrodynamic facilities at Upper Lodge, from left: RBC, office block & 30" tunnel

These facilities were instrumental in the design and development of the control and propulsion of ships, submarines and torpedoes. The main thrust of the work was to make them considerably quieter in operation by the reduction of cavitation and flow noise; a significant source of noise is the cavitation caused by propeller blades. The control and pump-jet propulsion for the lightweight torpedo STINGRAY was developed using the facilities at Upper Lodge. STINGRAY was the first UK torpedo to be equipped with such propulsion; subsequently the heavyweight torpedo SPEARFISH benefited from the work.

Post-WWII ARL research into machinery noise sources, propeller cavitation and long-range passive sonar came together in the design and construction of a new class of conventional (Diesel-Electric powered) submarine: the PORPOISE class of the late 1950s known as P-Boats. Their propellers were specifically designed for reduced noise by delaying the onset of cavitation. Propeller cavitation, arising from high rotational speeds, is a particularly loud source of noise that is easily detected. Both main and ancillary machinery noise reduction together with quiet propellers resulted in their radiated noise when snorting being a staggering 3% of what was previously the norm. Further, they were virtually undetectable when submerged and running on electric-drive. They and the similar, slightly later OBERON class (known as O-Boats) were the quietest of all NATO submarines and substantially quieter than Soviet submarines. Their quietness in operation made them ideal platforms for the ARL-designed long-range passive sonar, Sonar 2007 - prototype versions (codenamed SOAP Stage II) were extremely successfully trialled in HM Submarines SEALION (P-Boat) and OTUS (O-Boat) in 1965-6. The sonar, SOAP, was the culmination of ARL’s work started by the Acoustics Group (and continued by the Submarine Detection Group from 1959 to 1978) that dramatically expanded post-WWII as Passive sonar (long-range detection by listening for the noise radiated by other vessels) became a reality.

Royal Navy OBERON Class Diesel-Electric submarine

Production version of Sonar 2007 fitted in the Sound Room of HMS/M OTUS

SOAP was based on innovative digital processing of the underwater sound received by hydrophones (underwater microphones) fitted along the sides of the submarine. The digital processing concept was proven under an ARL investigation into long-range (>100 miles) submarine detection systems with large hydrophone arrays sited on the seabed connected to land-based processing and display in the Shetland Isles (codenamed CORSAIR), over the period 1952-7. Initial work on submarine-borne long-range passive sonar was commenced under the codename KNOUT, and involved multi-hydrophone arrays (topside arrays) experimentally fitted to the casing of T-class submarines HMS/Ms TIRELESS and THULE. The first service version of this system was engineered by HMUDE, Portland as Sonar Type 186. The signal processing of Type 186 produced a single fixed (unsteered) beam that meant the submarine had to be manoeuvred to search a wider area. This transpired to be a severe operational drawback. By 1957, ARL was considering ways of including (in a submarine) the multi-look signal processing technique used at AES Unst (produced under the codename DICE) for the Sonar 186 array. The cross-correlating equipment known as DICE 1 was used successfully at AES Unst in the key exercise NIGHTSHADE – the operational assessment of prosecuting land-based CORSAIR detections using aircraft.

From the late fifties, the evolving circumstances demanded that ARL's approach become considerably more practical. The strive for quieter operation of naval vessels created high demands on ARL’s radiated noise measurement and analysis section of the Acoustics Group, and the mid-1950s use of portable noise ranges gave way to further permanent ranges located in Loch Fyne, Argyll, Scotland and the Inner Sound (between the Scottish island of Raasay and the mainland and based on the isle of Rona.

Having played a major role in the reduction of machinery and propulsion noise radiated by conventional submarines, it was very much a case of back to the drawing board as nuclear-powered submarines, capable of much higher transit and sprint (underwater) speeds, came into service. The main machinery of the first few generations radiated high levels of self-noise that demanded some radical thinking and new technology to reduce power generation and propulsion noise, to evade long-range detection by passive means.

The high levels of self-noise besides making them easily detectable also had a detrimental effect on the performance of the sonars fitted to the submarines; passive sonar (186 & 2007) was adversely affected by the ever-present noise, and active sonar (2001) similarly suffered degradation by the flow-induced noise arising from the higher operating speeds. Following the demonstration of the intrinsic worth (in terms of operational advantage) of long-range passive sonar on quietened conventional submarines, ARL commenced development (in 1969) of passive sonar towed array technology to provide a comparable capability for UK nuclear-powered submarines. The research created the foundations for modern sonar employing digital processing techniques developed by ARL using specially-designed hybrid analogue and digital equipment, and general purpose computers. A by-product of this research was bespoke high-resolution (acoustic) analysis equipment (designed by ARL) used by ARL’s Acoustic Intelligence Group and the joint RN and RAF acoustic analysis centre, based at Upper Lodge, these together were key Naval Intelligence units during the Cold War.

The other significant break-through came as a result of ARL fore-fronting the incredibly successful (radiated) noise reduction of nuclear submarines and torpedoes with the use of pump-jet propulsion. Pump-jet propulsion had important operational advantages over conventional multi-bladed propellers: they generated a fraction of the noise for the same thrust and were considerably more powerful. This was an American concept that scientists at ARL, together with engineers at the Admiralty Experimental Works, Haslar, Hants, made work and was subsequently sold back! Pump-jet propulsion was a major output of the hydrodynamics work undertaken at Upper Lodge and was first evaluated on TON-Class Minesweeper HMS HIGHBURTON; HM Submarine CHURCHILL was the first nuclear submarine to be propelled by pump-jet propulsion, in 1970. The hunter-killer SWIFTSURE Class of submarine (in-service 1973) was the first to be designed with pump-jet propulsion and this drove the adoption of a less-tapered aft section (offering increased internal space), which is now a common feature of submarines; thus UK nuclear submarines were decades ahead of their contemporaries.

The process of the reduction of noise from the main and the myriad of auxiliary machinery of a nuclear submarine also bore fruit as the sources of noise were (painstakingly) identified and evaluated by ARL. These were suppressed by component redesign and with the use of rafts and flexible couplings; further reduction was achieved by sound absorbent and anechoic coverings, which ultimately led to their use on the outer hull of submarines.

1967 Visitors to ARL

As part of the (recent) reorganisation at ministerial level in the Ministry of Defence, some departmental posts disappeared and some new inter-service posts were created. One of these was that of the Minister of State for Defence (Equipment) whose responsibilities included a number of research and development establishments, and among these were several serving the special needs of the Royal Navy. On Monday 13th February, the new Minister, Mr Roy Mason, visited the Admiralty Research Laboratory in order to acquaint himself at first hand with the latest developments.

He was shown, among other items, progress in the use of sound in detecting submarines, basic investigations of flow noise, new ideas for ship propulsion and control, a TV presentation of movements of shoals of fish achieved by scanning with a high frequency sound beam, a portable meter for measuring radioactive hazards and a method of cleaning contaminated air drawn in quantities into ship's engine rooms.

In the above photo, the Superintendent ARL, Mr W.L. Burrows BSc DIC, is showing the Minister some of the features of the Rotating Beam Channel (at Upper Lodge) used to investigate the characteristics of new underwater weapons by towing them in a 100ft dia circular path. Mr F.S. Burt, Head of the Hydrodynamics Group (G-Group) is standing behind the Superintendent. Mr A.W. Ross the Director of Naval Physical Research (DNPR) is on the left of Mr Burt.

On the afternoon of Tuesday 10th October, ARL was visited by The Right Honourable Denis W. Healey MBE MP, Secretary of State for Defence. Mr Healey was accompanied by the Chief Scientist (Royal Navy) Mr B.W. Lythall CB MA. Mr Lythall, who had worked at ARL in the 1950s, was the scientific member of the Admiralty Board, formerly known as the Board of the Admiralty.

The visitors were received by the Superintendent, who escorted them to see some of the work of the Establishment. In the space of the limited time available they visited the Submarine Detection Group (L-Group), both at Queens Road and Upper Lodge, and the Hydrodynamics Group (G-Group) where the Rotating Beam Channel always proved of interest to visitors.

In the above photo taken in the RBC building are (from left) Mr W.L. Borrows Superintendent ARL, Mr F.S. Burt Head of the Hydrodynamics Group (G-Group), Mr Healey, Mr Lythall CS(RN), Mr Alec Mitchell (G-Group) and Mr Hastie-Smith Asst Private Secretary. Alec Mitchell was a principal figure in ARL's Pumpjet Propulsion research, and had the distinction of becoming the last Director of Admiralty Research Laboratory, upon the retirement of Dr E.(Ted) Lee in 1974; Ted Lee had also served at ARL earlier in his career.

In conclusion

I can think of no better way to conclude this history of ARL than to quote the final Director of the Admiralty Research Laboratory, and Hydrodynamist, Alec Mitchell, from his Journal:-

Perhaps the most important thing we had achieved had been to help in preventing another world war...



The above account of the work is rather centred on that of the Noise Ranging (measurement & analysis) and Hydrodynamics (self-noise reduction) Groups together with a portion of the work of the Submarine Detection Group, and virtually excludes the pioneering research by the Chemistry, Optics, Mine Countermeasures, Special Problems, Solid-State Physics, (Gunnery) Fire Control, Radiological Defence, Military Oceanography, Mathematics, Human Factors, Assessment, Instrumentation and Engineering Design, Groups of ARL.


Site Expansion

ARL underwent two expansions. In 1939 further Crown land within Bushy Park was acquired for a new laboratory block, officially named "Centre Block" it became known as 'Fire Control', and beyond it was built the 'Orlit Hut'. In 1945 ARL acquired a site in Bushy Park known as Upper Lodge.

Other ARL Sites

Over the years ARL established a number of outstations in the UK in support of the research; the majority set-up to serve a particular purpose.

Those outstations given the title Admiralty Experimental Station (AES) had  their title changed to Admiralty Research Laboratory Extension (ARLE) in 1969. Others (e.g. Loch Goil, Loch Fyne and Rona) had the formal title of Her Majesty's Establishment (HME).

AES / ARLE Perranporth

was situated on the North Cornish coast. This was the main ARL site for underwater acoustic experiments from ~1944 to 1972. As well as supporting a continuing programme of underwater acoustic propagation and transducer investigations, it played a pivotal role in ARL projects under the codenames: CORSAIR - long range, shore-based passive sonar, LIONESS - shore-based sea-area protection by active sonar, VERONICA - active sonar processing techniques, and APPENDIX - very long range active sonar. Control of this outstation passed from ARL's Acoustics Group (D-Group) to the Submarine Detection Group (L-Group) following the internal re-alignment of research in 1960.


was situated on the northernmost island of the Shetlands and co-located with RAF Saxa Vord. It was established in 1955 under ARL's project codenamed CORSAIR - long range, shore-based submarine detection. The purpose of AES Unst was
to evaluate techniques for land-based (deep water) detection of Soviet submarines in transit from their home base to UK waters (and beyond), such that they may be tracked, trailed and neutralised. Had the system proved operationally viable the site would have taken the title: Admiralty Marine Physical Station Unst. Initially under the control of ARL's Corsair Group (J-Group) it became an outstation of the Submarine Detection Group (L-Group) in 1960 for deep-water acoustics monitoring until its closure in 1977; the ARL building was handed-over to RAF Saxa Vord - see Gordon Carle's History of RAF Saxa Vord for more information on the location, the Admiralty Building and Underwater Cables.

Admiralty Marine Physical Station (AMPS) Portballintrae, NI

was set-up by ARL's Acoustics Group (D-Group) in collaboration with the Instrumentation Group (K-Group)  specifically as a level of protection to shipping in the Clyde Approaches, in 1953, under ARL's project codenamed CORSAIR - long range, shore-based submarine detection. From the outset, the intention of the underwater system was to provide a nominal course and speed of detected submarines such that other units could be directed to intercept the target. Unfortunately the sound propagation conditions were so poor that only ranges of a few miles were obtained. Therefore, it was impossible to carry out adequately the sort of operational investigations for which the station was envisaged. The station was shutdown for experimental work and the site cleared by May 1955. The resultant change of Naval strategy led to AES Unst - see above. 

ARL - Loch Goil
was established in 1942 by ARL's Acoustics Group (D-Group) as a quiet water, radiated noise measurement facility i.e. noise range. In 1950, it became part of a new organisation entitled Admiralty Hydro-Ballistic Research Establishment (see below) controlled by ARL. In-water facilities included a large floating laboratory moored on the Loch. Vessel radiated noise measurement and recording remained under the control of D-Group at ARL, initially the Acoustics Group and from 1960 the Noise Ranging Group, following the internal restructuring of the work.

ARL - Loch Fyne

A mobile range facility was initially used in Loch Fyne to relieve the workload of (nearby) Loch Goil, in the 1950s. With the ever-increasing requirement for noise ranging, permanent facilities were constructed in the early 1960s. Above, lower photo shows HMS/M WARSPITE submerging whilst tethered to moored buoys and powered from diesel generators ashore, for static radiated noise measurements. The static facility was also used by the Submarine Detection Group (L-Group), in 1971, to calibrate the transmit and receive arrays of an experimental longer range active sonar (utilising bottom-bounce together with novel signal processing) codenamed APPENDIX, fitted to HMS/M GRAMPUS. ARL's APPENDIX programme was aimed at improvements to the attack capability of the UK Nuclear Hunter/Killers.

ARL - Rona

A high (full) speed radiated noise measurement range was established c1963 with the operations and recording facilities based on the Island of Rona in the Inner Sound, to the east of the Isle of Skye. The radiated noise measurement range was sited between Raasay and the mainland.

As with the other ARL noise measurement ranges, the Rona range was designed, constructed, maintained and operated by staff of ARL's Noise Ranging Group (D-Group). The unique submarine dynamic distance measuring equipment designed and developed by ARL for the Rona Range was the first UK acoustic (synchronous) tracking system.

Spawned establishments

ARL’s Fire Control Group developed a concept of stabilised platforms successfully used for torpedo depth and direction control, searchlights, gun directors and guns. Such was the expansion of work and success in these areas that the Group evolved into the Admiralty Gunnery Establishment (AGE) in 1943, initially co-located with ARL at Queens Road it moved to Portland, Dorset in 1953.

A somewhat unlikely contribution, and an indication of the breadth of ARL’s research, is the Wave Group (formed 1944) work to predict the sea conditions for the Normandy Landings. Similar to the formation of AGE, ARL’s Wave Group was renamed the National Institute of Oceanography (NIO) in 1949 and moved in 1955. There's a suggestion that NIO moved to Haslemere, Surrey upon leaving ARL at Queens Road, prior to occupying a large site near Wormley, Surrey.

Establishments absorbed

Post-WWII reorganisation of the Admiralty's technical work resulted in the closure of the Admiralty Photographic and Instrumentation Research Laboratory, Kensington, London, which was known as april. The work and staff, absorbed into ARL in 1949 were accommodated at (newly acquired) Upper Lodge. Originally the staff were members of ARL's Instrumentation Group (K-Group). Following the internal re-organisation in 1960 K-Group was dissolved and the majority became members of the newly-formed Submarine Detection Group (L-Group).

The Admiralty Hydro-Ballistic Research Establishment (AH-BRE) was formed in 1950 by the amalgamation of three experimental facilities. These were ARL's in-water test facilities in Loch Goil (see above), the Admiralty Torpedo Experimental Establishment (TEE) water-entry test facilities at Coulport, and the Ministry of Supply (ex-Marine Aircraft Experimental Establishment) water-entry test facilities for air-dropped munitions at Glen Fruin. AH-BRE came under the control of ARL's Fluid Dynamics (Hydrodynamics) Group (G-Group).