Affray crest

Portrait of a Disaster

 A reasoned account to explain what may have happened to H.M Submarine “Affray” by Les Baker – a highly experienced ex-submariner and electrical artificer.

Les Baker

This thesis is reproduced by kind permission of Les’ widow Joan Baker – a good friend to Joyce and Kevin Cook.


Author’s Note

 This thesis does not concern itself with submarine achievements or ceremonious flag-waving, but to the inherent dangers where an established procedure pursues a programme to ensure protocol is maintained to the advantage of the few.

 Much nonsense and speculative guesses which can be described as a long succession of nuisances, which are easily precipitated and not even pigeon-holed by naval historians have been written about this affair.

Some minor events are a matter of deduction, but none of what is considered to be contributing factors in this tragedy are fictional. Here and there I have omitted unimportant details which cannot be confirmed positively, to avoid offending isolated personalities, but otherwise, I am convinced that this is a true account.

We are now able, thirty years afterwards, to judge the lesson to be learned from this affair.

 Seemingly, this thesis may appear to be a flagrant breach of trust, but history has shown that there was no alternative but to shoulder the cost of a proper system of training, which would ultimately produce the expected return to the individual, and subsequently to the establishment, which trained him.

My object, with the assistance of journalism, is to promote further critical public interest in the fate of the submarine “Affray” as a memorial to its complement.






1.1             When the S/M “Affray” sailed on that fateful day, 16th April 1951 at 4-15pm, on a detached simulated war patrol exercise named “Training Spring”, she carried a total complement of seventy-five. This comprised her new Commanding Officer, Lt. J. Blackburn D.S.C., and a nucleus of twenty-four retained crew members from her previous complement, together with twenty-five additional personnel, the majority from an entirely different class of S/M, joining “Affray” only three days before. The operational complement had been pared to this incredible minimum to accommodate the officer Executive and Engineering training classes, and a contingent of four Royal Marine Commandos, these trainees totalling twenty-six.


1.2             The recorded explicit instructions issued for this exercise were as follows:


Conduct as for a war patrol, dummy attacks on shipping, combining with mock hostile aircraft attacks, Marine Commandos to be landed by cockle-type canoes for a simulated sabotage and enemy observation exercise, then re-embark. Due Falmouth 1700hours 19th April, discharge Marine Commandos and their equipment back to base. Depart Falmouth 1700 hours 20th April, continue the exercisse, finally surfacing by 0800 hours 23rd April. Returning to Portsmouth, estimated time of arrival 1300 hours.


1.3             “Affray” had been instructed to proceed, surfaced via the Nab Tower to a mid-channel position, then to dive, motor or snort depending on the density of shipping, westwards down channel through the night. By approximately 0800 hours the next day “Affray” was due to surface in a predetermined area to standby for exercises with Coastal Command aircraft off the Cornish coast.


1.4             In accordance with these instructions, “Affray” headed West for passage through the Channel, signalled her position 50˚ 10 mins North - 01˚ 45mins West, her intention to dive as from 2115 hours, estimated .speed 4.5 knots.


1.5             “Affray” was due to make her surfacing signal by 0900 hours the following day, 17th April. No such signal was received.


1.6             1100 hours – “Subsmash One” was ordered. This signal was dispatched with full priority to all pre-arranged addresses and authorities concerned with the search and rescue of sunken submarines were immediately brought to “Standby”. Constant attempts were made to contact the missing submarine by powerful W/T transmitters.


1.7             1200 hours – “Subsmash Two” was ordered. This signal signifying beyond doubt that “Affray” was in serious difficulties. Effecting the instant dispatch of search vessels with supporting rescue craft to areas designated.


1.8             Why “Subsmash One” and “Subsmash Two” did not go into action two hours earlier is not clear. The procrastination exercised, contrary to the established procedure, must surely have been in default, and indefensible. This dilatory action may have been prejudicial to the eventual outcome of the search, and must be expounded in detail later in this thesis.


1.9             The search area, 77 x 20 miles = 1540 square miles, was monitored as quickly as possible by ships, aircraft and submarines. Of the many submarines involved in the search, “Sea Devil”, “Sirdar”, “Scythian” and “Ambush”, all separately reported picking up on their A/S listening equipment, hull tapping and faint intermittent distorted signals, which were unreadable and assumed to be transmitted from “Affray”. Continuous sweep searches were made to obtain a precise fix, but without success. Repeatedly, during the next forty-eight hours, false hopes were raised that “Affray” had been located. The action of vessels dropping intermittently batches of grenades, which was the accepted emergency signal to a submarine crew to escape, made the location and a fix more difficult to obtain. The last signals were reported by the submarine “Ambush” at 1439 hours, 18th April. The code letters which represent “We are trapped on the bottom” were clearly identified by experienced operators. The chronological sequence of these signals was recorded in the S/M “Ambush” control room log and in the Commanding Officer’s official report which was forwarded to Flag Officer Submarines Rear Admiral S.M. Raw, and subsequently to the Board of Enquiry.


2.0             All hope of saving life was finally abandoned on 19th April. Search vessels were dispersed except for H.M.S. “Reclaim”, a submarine rescue and diving ship, which was ordered to carry on the search until the submarine “Affray” was found.


2.1             In the following two months, H.M.S. “Reclaim” patiently investigated all the wrecks which had been plotted and located by A/S detection in the original search area, but without success. Finally, an escort group of frigates, commanded by Captain R. Foster-Brown, was instructed to carry out an A/S sweep running parallel and South of the original designated track; an area, thought by some officials to be of least probability. An A/S trace indicating the presence of a submarine was established in the first sweep, many miles South of the original search area, in the waters of Hurd Deep, an ammunition dumping ground. H.M.S. “Reclaim” was dispatched immediately to investigate with the aid of an underwater television camera with which she had been equipped only a few days earlier. The wreck of the “Affray” was positively identified on the 14th June, fifty-nine days after her disappearance. The location was approximately 40 miles from the reported diving position, and considered to be in “an area of relative improbability”, well outside the original search area, the distance supporting the phenomena of indistinct hull tappings etc. recorded by her sister submarines. No reference was made to the discovery of “Affray” in this unlikely location, and no official recorded plausible explanation was established.


2.2             There appears to be no record that anyone other than the writer envisaged the possibility of finding “Affray” structurally undamaged except for the collapsed snort mast, and in all probability outside the designated search area. Prior to these facts being known, precisely four days after “Affray” was reported missing, the writer advanced this theory, in writing, through the official channels. This proposition was passed through the preliminary stages of investigation, resulting in the recommendation that it should be placed on the agenda of the investigating Board of Enquiry to be analysed in detail – official records will confirm.


2.3             The reports of naval Boards of Enquiry are strictly confidential and, naturally, are never released for publication, however, this study could be classified as alien to the official view. That is why the author has expanded his work to include two appendices which are factual personal experiences which support this study. Concerning the Investigating Authority appointed subsequent to the disappearance of “Affray”, their known conclusions are intentionally ambiguous. Equally important, the validity of responsibility is not defined – a shrewd omission which this report will endeavour to highlight. My enquiries surprisingly revealed that no contact by the Investigating Authority had occurred with the Senior rates next-of-kin; much of my own factually relative material was derived from this source. This information was gleaned without coercion, the informants being totally unaware of the conclusions to be drawn from the innocuous interviews.


2.4             On the 14th November 1951, Mr J.P.N. Thomas, representing the Board of the Admiralty as Parliamentary Secretary, submitted in the House of Commons a précis, referring to the conclusions of the final report of the Board of Enquiry, stating that there was insufficient evidence to confirm with any certainty why “Affray” was lost. The possibility of salvage was condemned due to the complexity of the substantial diversion of resources and the subsequently exorbitantly high cost involved. It is difficult to accept this decree in such a bizarre situation, where a total of seventy-five lives had been lost, with the traumatic possibility of a repetition. The decision not to attempt salvage, although “Affray” was in a good condition except for the confirmed damage to the snort mast is questionable.


2.5             In the writer’s opinion, the raising of this submersible vessel would have been a comparatively easy operation and would have yielded much vital and decisive information. This declaration, opposing salvage, relegated to ignominy the loss of the submarine and her final complement. Although this decision could be considered as formal in approach, it leaves the reader reflecting on the fundamental issues. A decision to effect salvage would have been inclined to focus attention on the many undesirable aspects, surely placing the Establishment in an extraordinary position, resulting in an intractable solution to many problems surrounding this tragedy.


2.6             A further statement made by the Parliamentary Secretary, and I quote: “It is possible that a major battery explosion started as a shock wave in her hull, this ruptured the pressure trunking, which lies amidships under the casing but external to the hull”.


2.7             The writer endorses fully the first part of this statement, the second part which suggests that the external battery ventilation trunking ruptured, despite being tested to full diving pressure, is too weak to accept seriously, taking note that the snort mast is only tested to 45lbs per sq. in., and not subjected in any way to full diving pressure. As this information was obviously supplied by the submarine establishment, it must be asked, “How could this supposed battery explosion have originated?”


2.8             As no questions were placed before the “House”, the issue could not be debated, therefore, the fragility of Mr J.P.L Thomas’ statement could not be challenged.


Although the Parliamentary Secretary achieved his objective of shrouding the tragedy in a veil of secrecy, the open verdict engendered speculation.


2.9       ILLUSTRATION A     (Unfortunately these illustrations are no longer available) “A” Class Submarine Sectional Drawing



3.0                                     The writer’s purpose is not to provoke controversy, but to eradicate false suppositions, and make a concerted endeavour to co-ordinate the facts as they are known, to raise crucial questions upon the serious decisions which were taken, and leave the reader to proportion the responsibilities. It is inevitable that a survey of this type, which is a combination of history, personal experience and eye-witness reporting, will be viewed by some as over-critical and by others as not critical enough. But, in the final analysis, facts, and not theories, must speak for themselves. Thus, my main preoccupation has been to distinguish fact from the hypothetical, only then can anyone come to an informed opinion.


3.1             The loss of H.M. Submarine “Affray” is to many people little more than a dim memory and no-one can be certain what actually happened to cause this tragedy. Serious accidents to submarines have been, more often, the result of an accumulation of unforeseen events occurring before or following a mishap rather than the isolated serious defect. However, the events which have particular mystery in naval history will always be accepted as a challenge to the individual who have involved themselves intimately in their association. The author has, therefore, drawn upon eye-witness and next-of-kin accounts, together with relevant memoranda in an attempt to reconstruct as accurately and as objectively as possible the significant details related to this tragedy.


3.2             The writer, without embellishment, will portray a sequence of events, undoubtedly disturbing, as the almost certain probability which led to this disaster. Foreshadowed by the hasty and diverse assembly of the submarine’s complement, denied the opportunity of obtaining a proficient standard, due to the exigencies of the service.


3.3             The stage which now follow, leading up to this tragic loss have been extremely difficult to piece together in all their detail as the few relevant accounts available do not entirely agree. This is understandable as their full significance cannot be properly assessed unless one has experienced conditions complete in similarity, and possesses the ability to view the formulation and impact of incidents which appear to be a contributory factor.


3.4             A researcher who risks the wrath of the Establishment by surveying this disaster from a privileged and premeditated position, and raises crucial questions, in retrospect, which the author regards as essential, may find himself in conflict with those who genuinely believe that their primary role is to keep the “Affray” disaster a mystery at all costs, and the cynical few who take up an anti lower-deck pose. The author’s aim is to remove the mystique surrounding this occurrence, to demonstrate through simplicity, fact and, lacking all trace of pretence, to produce a reasonable and acceptable account of the main events which could be considered as the contributory factors to prejudice “Affray’s” safety; also, to expose certain false conceptions that arose during the aftermath of this tragedy and have remained unchallenged. Certain ethics have been carefully borne in mind throughout this study, in providing a fundamental and theoretical basis necessary for such a subject to remain within the limits imposed upon such work by the Ministry of Defence.


3.5             I have refrained wherever possible from portraying responsible participants, who should have provided an increasing awareness of an imminent collapse of safety precautions, whilst following procedures which were truly recognised as being hazardous in the extreme. Nevertheless, there are those individuals who had certain important roles in this affair who cannot entirely be screened from identification.

Although exhaustive trials were carried out on the ‘A’ Class type submarines in an endeavour to discover the cause of the disaster, the establishment failed to produce the possible sequence of events which could be accepted as a probability. However, one very disturbing fact emerged, that ‘A’ Class submarines, became unstable when laying on the sea-bed with one main compartment flooded. Should an escape attempt become necessary, the further flooding of an escape compartment would in all probability list the submarine on to its side. This remarkable phenomenon was an inherent defect in design, this was established by the ‘Controllers’ design and constructors office at the Admiralty. Modifications were made to improve on the limited escape facilities via the gun and conning towers, also bilge keels were installed to improve the stability. The instability of this Class of S/M under compartment escape conditions was kept highly confidential, creating a skilfully fostered illusion, owing to the conditions and hostile environment which would confront the crew in a compartment escape bid, once the flooding up procedure had started, it becomes impractical to revoke.

3.7       The aftermath of “Affray’s” loss and subsequent investigation, proved just how many stones there were to turn over in this highly sensitive area. In order to fulfil the function of writing a survey of this accident it is vital to understand the hazards which may have been the cause. But what, precisely, are the hazards? They are unsafe acts of persons, unsafe mechanical and electrical conditions, or unsafe environmental conditions.

3.8       The nomination of “Affray” for the role of submarine training, was obviously not a considered one. It is fair, I believe, to say that the use of “Affray” for this strenuous training programme under simulated war conditions came about not necessarily by decision, but by assumption. This assumption developed during the period January - March 1951, it is possible to trace the circumstances from which it emerged. It is the author’s firm opinion that the decision to use “Affray” regardless of her under- and unprepared state, precipitated the disaster.

3.9       The present study may not entirely bridge the gulf which exists between the established facts and the hypothetical, nevertheless, I hope the conception of this composite study, illustrated in the ensuing pages, will be of real value to those who are directly responsible for the administration and welfare of submarine crews. Although my approach is essentially practical, this thesis will also delve deeply into the theoretical. The whole concept is derived from a protracted and reasoned assessment of the many facets affecting this mystery, enhanced by personal experience.

4.0       It is vitally necessary, in the writer’s opinion, for the reader to become integrated with the broad general atmosphere of a submariner’s existence. Being mindful of the traditional flexibility that a true submariner has towards accepting exploitation, whether related to an operational sea going billet or a submarine undergoing dockyard refit. The demands of the service necessitate the total personal commitment of each individual in accepting abnormal difficulties. Submariners would be the last to claim a monopoly of exploitation, but whilst accepting the rigours commensurate with active sea duties, the environmental conditions, and the almost complete lack of support facilities during refits and maintenance periods were aligned with a bygone age, and, although tolerated, were incomprehensible.

4.1       A close study of the circumstances which surround the “Affray” during her brief dockyard refit, the apparent negative attitude of the submarine administration who were entirely responsible for the “Affray” complement, own limited potentialities, considering the resources available, i.e. general service S/M maintenance personnel sheltering under the safe umbrella of ‘no recognised procedure’ laid down to assist for S/M afloat and maintenance duties, will demonstrate how gravely the outcome of a brief and concentrated refit to satisfy a scheduled programme was prejudiced from the outset.

My observations reflect on the areas of neglected responsibility, and. anomalies practiced as a prerogative of the establishment, that is to say, by closeted senior administration officers, who have not access to your knowledge, and could not profit by it if they had, without disturbing traditional allegiances, it was the traditional thinking of that era, and underlined the submarine philosophy of the day.





5.1       The “Affray” saga really started on January 1st 1951 when the submarine entered Portsmouth Dockyard for major engine repairs. Her operational performance had not been satisfactory during her current commission, there were many recorded instances of exercises being abandoned because of defects. The “Affray’s” Commanding Officer was relieved of his command and the complement drafted upon entering the dockyard, retaining only a nucleus of the ships company, consisting of two officers, six senior and. fifteen junior ratings. Basically their responsibilities were security and liaison requirements during work in progress and trials necessary in dockyard refits, maintenance schedules, etc. Also the six monthly dry docking and check procedure was carried out.

The abnormal difficulties and problems which are common occurrence during dockyard refits, are all contributory factors which have a very serious effect upon the ultimate standard which can be attained. Any quality plan based upon planned maintenance is virtually impossible to comply with, unless sufficient trained and experienced personnel are made available, a compromise of standards is inevitably reached. The reader must be acquainted with the additional restrictions imposed, by leave periods, retraining courses, and sickness, which have an overall detrimental effect upon coverage of the docking schedule. The Captain, Lieutenant J. Blackburn D.S.C. was appointed and assumed command on 17th March 1951.

5.2       During “Affray’s” period in dockyard, a number of significant developments were recorded. Dockyard assistance was needed in freeing the forward escape hatch.

After “Affray” had carried out her preliminary main engine(s) trials in the tidal basin in Portsmouth dockyard on 9th April 1951, under load conditions, the engine-room compartment was subjected to a routine air pressure test 25 P.S.I. The writer declines to pass judgement as to whether the compartment air test was successful. That same evening No. 2 battery compartment was found to be contaminated with what was suspected as being a combination of fuel oil and salt water.

It was assumed that the contamination of oily waste bad penetrated the separating bulkhead between No. 2 battery compartment and the engine-room, below the top of the battery cell level, during the compartment air pressure test, without any real supporting evidence. Due to the prohibition of  pumping oily waste to sea in harbour, the engine—room and motor—room bilges would be at an exceptionally high level.

5,3                   ‘When the engine-room was shut down and sealed off prior to the compartment being subjected to an air pressure test, my conjecture, given credence by the accepted circumstantial evidence, is that the outboard drain of the master battery inboard ventilation valve was inadvertently left open. The continuity of this drain pipe is complete, terminating in the engine-room bilges, below the oily waste level, and not as normally in other battery ventilation trunking drains, via a ‘pigs-ear’.

The transfer of the contamination now becomes self-explanatory with the aid of an illustration.

ILLUSTRATION A2. (Unfortunately these illustrations are no longer available)

Battery ventilation system, showing No, 2 Battery compartment and engine-room trunking layout

The illustration shows the oily waste contamination entering the battery compartment and. spraying down on the top of the cells situated immediately below the battery ventilation trunking. These cells would. have been affected internally, in no way could they have escaped being contaminated, resulting inevitably in a major battery failure.

5,4       These two events of the engine-room compartment air pressure test and the battery contamination are inter-related, a fact which appears to have failed recognition. Even more serious aspects would undoubtedly be manifested in subsequent battery charging cycles. Should this occur during Snorting Routine, the hazard as described later in Sec.7 Par.8 would be substantiated.

In the writer’s opinion, the cumulative effect of these two gross errors of judgement, in failing to recognise the hazardous circumstances, must be considered as a contributing factor to the loss of the “Affray”. Being aware that a defect did exist, it is incomprehensible that the ship’s company, dockyard and the submarine’s administration did not institute a thorough investigation to discover how this contingency had occurred, and to establish to what extent the “Affray” was at risk.

My views and classification of responsibility, the specific areas where gross error existed will naturally be refuted by the Administration, I reserve the right to negate these anticipated denials, by personal experiences as related in Appendices I and II.


5.5. ILLUSTRATION 3 (Unfortunately these illustrations are no longer available) Submarine Battery Cell Construction

5.6 The behaviour of the defective cells will depend upon the severity of contamination, basically, the cells internal resistance will increase, increasing temperature, decreasing terminal voltage, reducing cells capacity. These characteristics will naturally be progressive with each cycle of charge, the only indication there may be, is the two battery sections will show differing charging rates. The rubber sheaths inside the Permali containers will rupture due to the very high temperature, should the leaks be small, main battery earths would become prevalent, earth leakage current readings would only be ‘apparent readings’ and not ‘true readings’, due t the subsequent propagation resulting in multiple earths. Should the rupture split the internal rubber sheath, the electrolyte would drain away very quickly, increasing the cells temperature in process, resulting in the battery section becoming open circuit. The reader is asked to refer to this condition when reading Sec. 7 Par. 8.

5.7       Repairs and. harbour trials were completed. on the 10th April 1951. The following day, 11th April, S/M “Affray” sailed with a reduced scratch crew for a check dive, engine trials and independent exercises. It is known that during these exercises the after-escape indicator buoy broke free, the buoy was temporarily re-secured to the casing. This mishap endorses the compromise which was prevalent in schedule maintenance routines where insufficient time and personnel were allocated during the six monthly docking routine.

5.8       Friday, 13th April the complement was made up to a full ships company, a close inspection will reveal the total inadequacy of its composition. The vital pre-requisite for any operational, submarine’s complement is professionalism, this qualification can only be acquired by a comprehensive ‘work-up’ period, this acquaintanceship gives the opportunity of complete familiarisation to meet all normal operating conditions. Why the decision was made not to give “Affray” the accepted comprehensive ‘work-up’ period is not clear.

5.9       Although the writer’s attitude may appear to be one of dissent, the primary object is to present a legitimate and accurate case history which will be shown to be appropriate and reasonable, particularly in the judgement that the submarine service had increasingly committed itself beyond its means to provide the manpower to absorb the additional demands, and adopting a policy of reducing the amount of support to a minimum wherever possible.

6.0       During the transitional period of investigation and trials following the loss of “Affray”, an unprecedented situation faced the Submarine Authority, with the belated discovery that lethal decompression conditions could easily be obtained during snorting operations. Besides the simple mathematical proof, all snort masts and head valves were subsequently redesigned. The snort masts were made larger, head valves were altered to dual seating, preventing the valve from being retarted in the shut position. All ‘A’ class submarines were not permitted to snort until this expensive and time consuming modification was carried out, wider the guise of snort mast weld, examination, surely a rudimentary masquerade.

My exploratory investigations into a submarine under snorting conditions can be paralleled to aviation physiology and should have influenced the thinking of the Naval medical profession for the welfare of the submariner, although environmental conditions are dissimilar, the physical limitations are undeniably identical.

6.1.                  The high standard which has been achieved in the efficiency and safety of submarines during snorting operations, has not excluded the probability of their having to be abandoned to meet the needs and. differing circumstances during arduous exercises. Although the criteria which gives precise limits and conditions that the submariner is expected to withstand, and. those to which he should not be exposed, are clearly laid down. I have had experience where the safety parameters have been impaired, in varying degrees, to satisfy the level of optimum performance. It is, in my opinion, these compromises which determine the safety factor.

The Submarine General Memorandum 1951 does not confirm any attempt to orientate Con Officers of the hazard to health and safety during snorting operations should requisite standards be broken.

6.2       In the Submarine Service, the price of safety and efficiency must always be unrelenting vigilance and training; the science of safeguarding people and machinery from operating errors called ‘accidents’ is not enough. The reader at this stage must be reminded that every member of an operational submarine’s complement has many important tasks and responsibilities to discharge; in the era of “Affray” the complement would have been sixty-one fully trained personnel. However, if readers study the statistical table they will observe that there are only forty-nine actual crew members, of these, twenty-five only joined the submarine just three days before finally sailing, which unfortunately included a week-end sandwiched in between.

6.3       The first question that must be asked is, why and who made the decision to use a submarine which did not carry a fully trained operational complement for such an arduous peace-time exercise? This question is endorsed by the official report letter No. S/M 1016/110 28th April 1951 which reads as follows:

‘The complete crew had not worked up together to the extent of becoming fit to take part in tactical exercises. It was considered that this cruise would provide valuable experience in that direction, despite the absence of the majority of the junior rates which bad been replaced by the training classes’

6.5       The previous report conflicts completely with Captain S/M H.C.Brown C.B.E. D.S.O., Commanding Officer of the 5th S/M Flotilla, Memo No. 567/108 3rd April 1951, which calls for the conduct for this exercise:

“ …as for a War Patrol, dummy attacks on shipping, mock hostile aircraft attacks, Marine Commandos to be landed by folboat (collapsible cockle type of canoe) for a simulated sabotage and enemy observation exercise.”

6.6       Another quote-worthy report issued in Rear Admiral S.M. Raw, Flag Officer S/Ma Flotilla’s letter No. 916/202/1 4th May 1951 which reads as follows:

‘HM. S/M “Affray”, was, in my opinion, sufficiently worked up in every way and in a fit condition to undertake a training War Patrol’.

6.7       These quotations are contradictory in the extreme, and, the latter completely at variance with the facts. Here we have a much reduced ships company, who bad not passed through any preparatory pro of working up together, lacking expert professionalism and skill, many experiencing a different class of sub for the first time, with the extra burden of the training classes of Engineering and Executive Officers, who were entirely without practical submarine experience, making up the actual complement, although they had never experienced the environmental conditions of a submarine under operational routine.

6.8       The undeniable success of the submarine safety record is its demonstrable professionalism of S/M complements, however, the exigencies which existed upon this occasion imposed severe limitations. The system of selecting crews by joint consultative means, as then practised, was designed to obviate an individual error of judgement the apparent complacency displayed by the administration authority in adhering to this system was surely ill-founded, as the crew-manning statistics do not express normality regarding the composition of the submarine’s complement selected for this exercise.


7.1       “Affray” was one of the submarine flotilla attached to H.M.S. “Dolphin”, the premier submarine depot based at Gosport, commanded by Captain B.C. Browne C.B.E., D.S.O. Lt. Cdr. 1.5. Stevens was Staff Officer Operations to Captain S/M, duties being involved with organising, the control of exercises and operation of attached submarines. Operation orders were drafted and agreed with Lt. Blackburn, “Affray’s” commanding officer, and approved by Capt. S/M. B.C. Browne.

7.2       At 1700 hours on Monday 16th April 1951, Lt Cmdr. I.S. Stevens, in the absence of senior officers, attended the departure of “Affray”. Later, at 21.16 hours South of the Isle of Wight, “Affray” reported she was diving as instructed, her signal would be made between 0800 hours and 0900 hours 17th April.

The following morning at 0800 hours the duty officer reported to staff officer operations, Lt. Cdr. I.S. Stevens, that nothing of note bad occurred during the night. By 0900 hours “Affray’s” safe diving time had expired, and no surfacing signal received.

7.3       Flag Officer S/Ms Rear Admiral. S.M. Raw was informed at his official residence, Dolphin House, Alverstoke, Gosport., at 0920 hours, he was recorded as passing into H.M.S. “Dolphin” at 1000 hours; finally at 1100 hours Subsmash One was implemented, followed by Subsmash Two at 1200 hours.

7.4       Whether this unexplainable delay had any prejudicial effect upon the result of the ultimate search cannot be established, as there was no exact way of predicting a time scale. By exercising discriminatory action in not following the established procedure of implementing immediate Search and Rescue routine was without precedent, the evidence appears to be amazingly explicit against the submarine administration. What is perhaps more disturbing, is that such activities were treated as mundane and inevitable, they were thus given the acceptability of normality.

7,5       The writer considers he has filled in any gaps and cleared up any anomalies which may have existed, building up a picture interpretable at least in its broad composition realistically without sensationalism.

7.6       H.M.S/M “Affray” was one of sixteen ‘A’ class submarines of normal British submarine design. Propelled by diesel engines and electric motors driven from storage batteries, there were two battery sections, each consisting of 112 cells connected in series, with battery sections connected in parallel. No.1 battery section was housed in a battery tank below the accommodation space. No. 2 battery section was housed in a battery compartment below the control room; each battery section was identical, having a capacity 6,630 ampere hours, at the five hour rate of discharge, suitable blow out fuses and isolating links were part of the protective devices. The auxiliary circuits were supplied via two ring mains, the constant pressure ring main supplied the main lighting and. other circuits which were designed not to take the increase voltage during charging, the voltage con- was obtained by a reducer. The variable pressure ring main supplied all auxiliary heavy machinery designed to operate at a voltage 190—315 volts.

ILLUSTRATION A4   (Unfortunately these illustrations are no longer available)



7.7       The snort induction system is a device which enables the submarine to run its diesel engines whilst submerged at a shallow depth for propulsion, charging batteries or the combination of both. The snort mast is vitually an air pipe, safeguarded by a system of shut off valves, these valves were either hand. or water operated. There are particular hazards to safety when snorting which the writer feels it necessary to emphasise.

The main hazards to safety during Snorting Stations are as follows:

1. Water entering the snort induction hull valve so rapidly that it may sink the submarine.

2. Going too deep with the engine(s) running, water floods back through the snort exhaust due to the increasing back pressure, damaging the engine(s) beyond repair. The generated carbon monoxide gas being discharged internally in the submarine via the relief valve operated by back pressure.

3. Loss of trim; snort head valve shuts, engine(s) are running. An accelerated decompression situation below 560 mm Hg (22.)”) is easily reached within seconds, and the air pressure will continue to fall rapidly unless the snort head valve opens, or the engine(s) are stopped. The results affect individuals differently, varying from extreme physical and mental depression, marked defect in judgement, apnoia, paralysis, hypoxia and stupification, some individuals will not know where they are or what they are doing, whilst others may have their faculties under reasonable control. This physical change is brought about by the loss of differential partial pressure within the body tissues, causing acroembolism. These symptoms are only a generalisation the comprehensive details are beyond. the scope of this report.

Reference can be made to the examples taken from the published text books as follows :—

A. ‘Principles and Practice of Aviation Medicine’ by HG. Armstrong M.D.

B. ‘A Textbook of Aviation Pbysio1o Edited by J.A. Gilhies.

C. ‘Aerospace Medicine’ by Hugh W. Raidel M.D.

            4. Charging the main batteries whilst snorting. Should one cell open circuit in any of the two battery sections (224 cells) possibly caused through corrosion of the inter-cell connections, or any one cell lose its electrolyte, results in possible fire and minor explosion.

7,8       A much more serious effect will be the engine(s) increasing their revolutions due to the sudden loss of norma]. load, conditions which will interrupt supplies to the constant pressure ring main, affecting lighting, indicator and. low power services, coupled with accelerated decompression as previously referred to in Sec.7. Par.7.

The battery ventilation which has to be running at full speed during battery charging cycles, discharges above, but on to the starboard engine—room control position. In such a situation where poisonous ignited hydrogen gases are enveloping what is left of the norma]. atmosphere, only rapid decisive action can prevent a total disaster from occurring.

7.9       ILLUSTRATION A5  (Unfortunately these illustrations are no longer available)


The paradoxical based upon experience as related in Appendices I and II will form the guide lines on the following hypothetical exposition, given credibility by the accumulated evidence.

8.0       The first, and possibly the most important point that must be established and accepted, is that the “Affray” was operating under snorting conditions at the time of the first incident which marked the beginning of the accident. It is considered that the majority of readers will be in firm agreement, remembering the substantiated report from the divers.

To acquaint the reader with the basic watch keeping procedure of a submarine at sea, the ships complement are placed in three watches to suit the need for normal requirements, the minimum sea ratings required would be fifteen. but only five were carried, which would mean the Officers Training classes also being in three watches, obviously resulting in many instances of the trainees not being supervised by experienced senior ratings and ships officers.


8.1       Stage I

The “Affray” is at periscope depth, watch diving, one third of her complement closed up on watch, Snorting Stations are ordered, (one shaft only). Propelled by one main motor with shaft coupling as follows: Tail clutch ‘in’, engine clutch ‘out’, Snorting on the opposite shaft, engine clutch ‘in’, tail clutch ‘out’, charging the main batteries.

ILLUSTRATION A6  (Unfortunately these illustrations are no longer available)


8.2       One or more cells of No. 2 battery section open circuit due to the defect as previously described in Sec. 7 Par. 8. The diesel engine instantly increases revolutions due to the sudden loss of normal load conditions, the reducer controlling the constant pressure ring main will also open circuit due to the over-speed trip operating the reducer selector switch to ‘fail safe’, isolating normal lighting circuits, further increasing the generated voltage as the auxiliary load is reduced, blowing the supply fuses of the remaining police lights from No.1 battery. The submarine is now in almost complete darkness except for small battery hand lamps (Oldhams).

8.3       Stage 2


The snort head valve operated by its float has shut, the head valve has dipped because of the swell or loss of depth, initiated by the behaviour of the watch officer or hydroplane operator’s loss of control due to the sudden and catastrophic change from normal conditions as narrated in  Sec. 7 Par 7.

The engine(s) run on’ the air in the S/M, which acts as a reservoir only for a very short period 10/15 seconds. Air pressure begins to fall instantly, the hydroplanes are put to hard to rise to try and gain correct depth. The ballast pump, which controls the pumping in and out of water ballast from the internal trim tanks has already been ordered to pump to sea.

It must be accepted that the loss of depth when snorting is very common due to the enormous amount of water taken in with the air, which is drawn in via the snort mast with great velocity, depending on weather and sea conditions.

8.4       The main engines can be stopped by orders issued by the Officer-of-the- Watch in the control room, or by the senior rating on watch in the engine- room without orders, providing that he considers that the air pressure is falling too quickly and has reached a dangerous level (22.0”).

A cautionary note should be added here, the group exhaust and the snort muffler valves must be shut at the same instant as the diesels are stopped, to prevent flooding back through the engines, the snort induction and emergency flap valves are shut to coincide with these operations. At the same time, the switches have to be broken which control the generated power to the main batteries. The engine clutch is put to the ‘out’ position, and the tail clutch is put to the ‘in’ position, ensuring that any subsequent telegraph order(s) can be obeyed immediately by the main motor(s).

Only one experienced senior rating actioned all these operations. Should the factors be allowed to develop as already described in Sec. 7 Par. 7 ‘the point of no return’ has already been reached.

8.5       Without fear of discrimination, the writer must re-assert that any violation to the acceptable standard procedure was entirely due to the lack of experience and cohesion among the ships complement when faced with an unplanned event. In support of this accusation, it must be remembered that there was no electrical artificer on board, this omission to the normal complement has never been explained. The senior electrical rating on board was only an Acting Petty Officer Electrician, entirely without sufficient experience to compete with any non-standard occurrence.

8.6       ILLUSTRATION A7 (Unfortunately these illustrations are no longer available)


8.7       Stage 3

On the generating shaft, the diesel engine loses speed and power due to the rapidly decreasing air pressure, the generated voltage falls below battery voltage, the generators becoming main motors and keep the labouring engine turning over, further decreasing the air pressure. Due to the increasing back pressure, the engine reliefs will open, resulting in carbon monoxide gas being discharged internally in the S/M, particularly affecting the engine—room and motor—room personnel. This state will continue until the load, becomes too great and the inline motor fuses are blown.

The H.P. air compressor(s) would continue to run, further decreasing the air pressure.

8.8       Stage 4

At this stage the “Affray” is still being propelled on one shaft driven by the one main motor. Because both hydroplanes were hard to rise, and the anticipated action that would have been automatically taken by the Officer-of-the-Watch to regain neutral buoyancy by pumping to sea before being overwhelmed, the “Affray” may well have gained a partial surface condition for a considerable period, the snort mast head valve would have remained shut due to the very low air pressure keeping the valve tight upon its seating.

8.9       The submarine would continue being propelled in an uncontrolled state until such time as her battery was discharged, or until she became negatively buoyant and slowly sank. This theoretical situation may irradiate the reason why Affray” was finally discovered some distance outside her estimated patrol area, not covered by the original search.

9.0       Stage V

The snort mast would fracture most probably as she hit the sea bed, this fracture would obviously take place where the pressure is the greatest, at the heel of the mast, as the mast is not tested. to full diving pressure only 45 lbs Sq. in. The submarine would start to flood, as the flooding takes place, the air pressure will rise, resuscitation will take place, some members may be sufficiently revived to seal off a compartment. The possible origin of signals and hull tapping picked up by the searching submarines presumed to be emanating from the S/M Affray must be endorsed.

No importance should be attached to the bridge telegraph showing stop, as this exercise was to be simulated war patrol, the bridge telegraphs would be disconnected as a routine procedure.

9.1       It is seriously hoped that the reader is fully convinced of the affinity of purpose that sufficient evidence has been supplied and not simply a theoretical exercise. The writer will be satisfied if he has provided a platform for discussion, to take a bard critical appraisal of the facts, now these beliefs have been revealed. They are obviously supported by practical experience which is outside the scope of this report.

10.0    Conclusion

This has not been an easy thesis to write, one’s knowledge of the subject can be an embarrassing encumbrance. There is an element almost of treachery in striving both to be truthful and objective to strike a fair balance. Officialdom doesn’t respond well to an argument from reason alone, the authenticity will remain a matter of opinion, a dignified controversy, the official attitude will be naturally in keeping with its traditionally cautious behaviour. So called infallible pronouncements by private revelations are discouraged, and are only accepted as inspired ‘hunches’ that is why obedience, to fact, and logic will be found to be most disagreeable to some sections of the establishment.

To assist the reader to formulate an opinion of the more important aspects it is necessary to take a closer examination of the significant issues involved.

10.1                1) Was the workup adequate in all respects to carry out their expected functions during the dockyard period - dockyard operational liaison during the main engine overhaul and subsequent trial programme, six monthly dry docking and all the inspection and relevant  testing, carrying out maintenance schedule conforming to standards of operation and above all safety procedures?

10.2                2) Was there in existence any reference manual of technological instructions, other than the suppliers handbook, for the S/Ms main battery?

10.3                3) Was the re-commissioning of Affray” Friday 13th April 1951 by her ships company, given adequate time to become completely familiarised and reasonable efficient as an operational team, to accept the responsibility of the training classes composed of executive and engineering officers, together with Royal Marine Commandos on a simulated War Patrol ?

10.4                4) Was it a standard code of practice, for training purposes, to interrupt, without warning, power supplies to all lighting circuits when the submarine is dived, snorting and charging batteries ?

10.5                5) Was the Officer—of—the-Watch sufficiently orientated to act appropriately in the unlikely event that a battery section open circuited when snorting, and to function correctly in a situation as previously described in Sec. 7 Par. 8?

10.6                6) Was it accepted that an ‘A’ class submarine could, when snorting, create a hostile environment, so rapidly, to cause unconsciousness without warning ?

10.7                The answers to these simple and rudimentary questions is ‘no’, that is why the writer agreed on a concept which was to achieve certain objectives, to dislodge any theoretical surmise in this private inquiry by supporting the final analysis with facts, and. being only too aware that the establishment would naturally apply a kind of built-in resistance to other people’s ideas. One wonders what might have been the result, had the establishment of those days displayed the initiative and foresight with which the Drafting Control of a. more recent period has been credited.

10.8                One final question which must be asked, was the result of the search and rescue organisation alerted by the receipt of signals, Subsmash I and Subsmash II affected adversely by the procrastination exercised in their dispatch ? The answer is naturally one of speculation, if the sequence of events as described in Sec. 8 Par. 8 are a true account, then the time scale that “Affray” remained in a partially surfaced condition is an important question indeed.

10.9                Finally, a deep and. sincere wish that the publication will not aggravate the aggrieved feelings of the “Affray” ships company dependants.






H.M.S/M Affray         ‘A’ Class Submarine

Length 282 ft. Beam 22 ft.            Displacement 1120/1620 Tons.

4300/1250 H.P. 8/18 Knots. Complement

Completed. 1945.   Lost 17th April 1951.



The purpose of these two Appendices is to elaborate on experiences briefly mentioned in the accompanying thesis, which I felt required a wider context and more allegorical treatment than could be given there.

To supply evidence of the administration and subsequent events, which could have resulted in another unexplained submarine tragedy.



1.1       H.M.S/M “Astute” Re-commissioned January1955 at Devonport Dockyard after an extended refit. Her Commanding Officer was Lt. Cdr. P. Dowling.

After commissioning the submarine and. her complement were subjected to the usual standardised ‘work-up’ period of approximately six weeks. During March, “Astute sailed to H.M.S. “Ambrose” as the first submarine nominated to form the 6th S/M squadron on loan to the Canadian Navy, based at Halifax, Nova Scotia.

1.2       On arrival in Canada, it was found that the starboard main motor was flooded with salt water, this contingency being caused by a defect in the cooling water circulating system.

This defect reduced the performance of manoeuvrability, charging of batteries, and propulsion when dived, by fifty per cent. Nevertheless, with this severe defect Astute” sailed immediately for exercises with the Canadian Navy, entirely detached from her base without any support facilities for eleven weeks.

1.3       It was during this period a decision was taken that when opportunity afforded itself, the submarine would carry out the qualifying deep dive which it had been unable to carry out during the ‘work-up’, due to the urgency of placing ‘Astute’ on station.

1.4       Twenty-four hours before the deep dive was scheduled, the main ballast pump developed a mechanical defect, necessitating a complete strip down. Notwithstanding these two major defects, starboard main motor and the main ballast pump out of action, the deep dive was carried out.

1.5       After eleven weeks of concentrated and prolonged exercises, “Astute” returned to Halifax, overdue for self maintenance (Fourteen days) and refurbishing of the defective starboard main motor. Eighteen field coils were replaced and all the auxiliary work made good by her own ships co the submarine becoming operational after her maintenance period without any delay.

2.1       It became apparent as the commission progressed that the main battery was suspect to failure, due to continuous overworking at very high temperatures, resulting in the cells breaking up internally. Supporting evidence that the plate separators were disintegrating was presented to the ships officers repeatedly, with emphasis on the hazard to safety if “Astute” was kept operational under these high risk conditions, these precautionary warnings were brushed aside, with no action being taken.

2.2       Departing from the Navy Yard, New London, United States for a three week extensive exercise with units of the United States Navy, number one battery section open circuited, resulting in an explosion, fire, failure of the constant pressure ring main, and police lighting circuits simultaneously. Immediate appropriate action was taken to contain the situation and the ‘Bridge’ informed, the order to ‘clear-lower-deck’ and muster on the bridge was passed, leaving below one electrical rating to operate the switch-boards, one helmsman and the Chief Electrician to take whatever action he considered necessary.

After a safe interval the accommodation compartment was entered for damage assessment, the battery boards situated directly above the defective cells were found to have ballooned by the force of the explosion, smoke and. hydrogen flame t was apparent. A comprehensive report was made to the ‘Bridge’, a return to normal routine was ordered.

2.3       Defective cells were isolated and a corresponding number to compensate for voltage loss were cut out from the remaining battery section.

The three week exercise commenced on schedule, upon completion of the exercise programme, “Astute” returned to base at Halifax for self maintenance during which the battery again caught fire. A hydrogen contents trial was carried out resulting in total condemnation of the main battery. Withdrawal of “Astute” from the 6th squadron returning to the United Kingdom under ‘passage routine’ was considered, but not actioned, the official and recorded reason being, that the calculated risk was not acceptable.

2.4       The embarrassing alternative was adopted in the immobilisation of “Astute” for approximately six months until a replacement battery could be made available from the U.K., in this period “Astute’s” safe diving time had expired.

2.5       Could the “Affray” ships company have been faced with a similar sequence of events, as described and repeated in the attached thesis Sec. 8 Par. 2? The utter lack of that mental and physical preparedness which is essential to enable quick reaction to the needs of the moment, and that this unpreparedness was responsible for the extraordinary paralysis aboard “Affray” which had taken the ships company by surprise.

2.6       The writer considers that it would be extremely doubtful whether any Submarine Administration would endorse the calculated risk to operate a submarine with such a. narrow margin of safety as exercised throughout “Astute’s” commission, despite vindicatory circumstances surrounding the loan period. This being - assessment of the operational ability of a British-type submarine, which would ultimately influence the decision of the Canadian authorities whether to equip their navy with submarines of British construction.

Sufficient to remark, “Astute” achieved results far beyond what was considered possible.



1.1       H.M.S/M “Token” Re-commissioned April 1948 at Cammell Laird’s dockyard, Birkenhead after an extended refit.

S/M “Token” Commanding Officer Lt. J. Blackburn

1.2       During “Token’s” initial acceptance trials with civilian representatives on board, it was found that all three main battery sections were heavily contaminated with an oily salt water solution.

It was immediately assumed that the contamination had penetrated into the battery tanks from the main line, via the locked battery suction non-return valves.

The assumption was that the seating of these valves had contracted during the refit, allowing seepage during the use of the main line. This supposition was reiterated when signals were dispatched, signifying a delay in the departure date from the dockyard of approximately two weeks.

1.3       As the Petty Officer Electrician, I firmly disagreed with the assumption that the defect had occurred as described and supplied, supporting evidence of the alternative explanation as follows:

Following the completion of the main engine trials prior to sailing for acceptance diving exercises, the engine motor-room compartment was sealed off for an air pressure test 25 lbs sq. in. When the compartment was shut down, the outboard drain valve of the master battery inboard ventilation was inadvertently left open, this drain discharges into the engine-room bilges, unlike other battery drain systems where the drains pass into discharge via a ‘pigs ear’, the drain in question is complete in continuity. Due to the prohibition of pumping oily waste to sea in harbour, the engine- room bilges were at an exceptionally high level after the completion of the main engine trials. The transfer of the contamination now becomes self-explanatory, (see supporting line diagram)

(Unfortunately these illustrations are no longer available)


1.4             The entire battery had to be removed, tanks cleaned and contaminated cells renewed. “Token” became operational two weeks behind schedule.

1.5             ‘Restricted’ memoranda could not have been circulated to alert Commanding Officers of this design fault, because two further ‘A’ class submarines “Alaric” and “Astute”, later commissioned by the writer, were similarly fitted.