The G7 Mystery

Developments in side scan sonar technology and the popularity of sports diving have resulted in the discovery of many Blyth and Tees submarine wrecks in recent years. HMS/M Swordfish was found off the Isle of Wight in 1983 by a sports diver (the boat had been dispatched to Portsmouth to carry out anti-invasion patrols at the time of her loss). Seahorse was found off the Danish coast in the early 1990s. In more recent years HMS/M Unity, HMS/M J6 and the mine-layer Narwhal have been found, the first by sports divers, the latter by a team of Polish surveyors hunting for ORP Orzel. Two wrecks remained stubbornly elusive, HMS/M G7 and HMS Spearfish. Here we are concerned with HMS/M G7 but her fate was inextricably linked with that of her Teesside stablemate G8.

Both submarines had been built on the Tyne. While the 10th Flotilla had long been considered as an unlucky unit by submariners, a situation borne out by losses, the 11th Flotilla was considered just the opposite but by October 1918 things were about to change for the Blyth submarines with the losses of J6 and G7 within the month.

Both G8 (Lt. John Tryon) and G7 (Lt. Charles Russell) were posted as missing, lost with all hands in 1918, G8 (thirty-two lives lost) in January and G7 (thirty-one lives lost) in November. The enemy made no claims to have sunk either of them and as usual in such cases, loss was attributed to mining. It was assumed that G7 had been lost close to her patrol zone off the Little Fisher Bank.

From the 1918 chart above published in Spindler, Band 5 it will readily be seen why it was concluded that G8 and G7 had likely been mined. Both sides intensively laid mines off the German coast. Yet the Little Fisher Bank had not been mined as the chart above demonstrates and the transit routes adopted by the Blyth and Tees submarine flotillas were selected largely because they were known to be free from mines. Loose mines were endemic however. So what is known about the last patrols of G7 and G8 ?

G8 left the submarine depot ship HMS Lucia moored at Eston on the Tees at 15:00hrs on 27 December 1918. G8 did not sail alone but instead left in company with G12 and the 10th Submarine Flotilla destroyer, HMS Medea. G8 was to take up a billet (patrol) in the Kattegat, her station being East of Hirsholm Island (off Frederickshavn) during daytime and North of Laeso Light (Norder Ronner Fyr) during darkness. G8 was ordered to commence her return on January 3, 1918, or possibly forty-eight hours later should circumstances require (This is a clear indication that this was an intelligence directed patrol and that Room 40 was expecting German warships from Kiel to transit the area via one of the Belts). G8 was expected to be back on Tees by January 6. She failed to return and was officially declared missing on January 14, 1918.

G7 was also based on the Tees with HMS Lucia and like her stablemate G8, she was a veteran of anti submarine and scouting patrols on behalf of the Grand Fleet. It was a thankless task. On April 15, 1917, G7 had been patrolling between Lerwick and Bergen when submarine U-30. G7 fired a torpedo at U-30 and after an exchange of gunfire the German submarine dived away. Although U-30 escaped unscathed, G7 had interrupted attempts to sink two Norwegian merchant ships, Draug and Svanfos.

Possibly to counter the threat of an imminent HSF operation, G7 was transferred from Lucia to Titania and the 11th Submarine Flotilla in September 1918. G7 (Lt. Charles Russell) cast off from Titania at 06:45 on October 21, 1918 for what was to be her third patrol from Blyth. This was Lt. Russell’s first patrol as Captain but his crew were veteran submariners.
G7 was replacing her ‘chummy boat’, G10 on station off the coast of Denmark and likely both boats followed the same outward track as described in the surviving September/October log preserved in ADM 173/2424. 

This was at a time of heightened tension because Room 40 was assembling information that a final major sortie – a Gotterdammerung – on the part of the High Seas Fleet (HSF) was imminent. Ever since June 1918 HSF U-boats had been assiduously laying the ‘Bell Rock Arc’ – belt of mines designed to snare Grand Fleet units based on the Forth.  Room 40 expected the UC boats to extend these minefields southwards thus posing a hazard to the 11th Flotilla submarines based at Blyth a well as Grand Fleet units based on the Forth.  During the afternoon of the October 23 the Admiralty warned the Commander‑in‑Chief Grand Fleet that the situation in the North Sea was ‘abnormal’ and that they were ordering destroyers from Plymouth, Dover and Buncrana in Ireland to reinforce the Grand Fleet flotillas.

Anti submarine/scouting patrols on the part of the 10th and 11th Flotilla submarines were organised to intercept the HSF en route. At 05:56 on 23 October, G7 was ordered by Captain (S) 11, Stanley Willis to enter a billet ‘West of Little Fisher Bank’. This was a regular route taken by HSF U-boats transiting Weg Rot bound for waters off Northumberland and Scotland. This order was acknowledged by G7.  At this stage the boat must have been approaching her patrol zone.  G7 did not return and was registered as lost with all hands on November 1, 1918. Ten days later that long transport of agony known as the Great War came to an end.

And that was that. The vade mecum of British submarine losses, Evans’ ‘Beneath the Waves’ barely affords a line to either of these submarines. They and their crews disappeared without trace and were simply forgotten about. In 2011 there was a flurry of indignation when footage was taken of a Danish vessel raising a conning tower off Nymindegab on the West coast of Denmark. Tabloids and British government departments screeched with indignation that a British war grave had been violated for filthy lucre and either G8 or G7 was thought to be the likely victim. Faced with a barrage of criticism the Danes claimed that the tower was simply lying on the sea-bed apart from the wreck, having been inadvertently torn off by trawlers and that they had not salvaged the conning tower for its metal content. Ultimately the restored conning tower of E50 ended up in the Sea War Museum, Thyboren, where it is a much-prized exhibit.

Two points emerged from this embarrassing affair. Firstly, a war grave had indeed been violated, secondly the submarine in question was not that of a ‘G’ class boat but belonged to HMS/M E50. E50 was thought to have been mined off the South Dogger Light Vessel in February 1918. This is now known to be incorrect. The hunt for the missing ‘G’ boats had once again gone cold.

Then in 2015 Marine Quest divers based at Eyemouth chanced upon a submarine wreck off the Northumberland coast in the sector known as the Farnes Deep.

From the mid 1990’s sports divers began exploring the Farnes Deep, an area of significant ecological importance charted roughly around 55° 33′ N, 1 °0 W. The name is curious because it is a significant distance from the Farne Islands and thirty or so miles offshore from Seahouses. The historical reason for the concentration of so many war time wrecks here is because the Longstone/Lista route, the track between the North East coast and the mouth of the Skaggerak ran through this area. Not only was it heavily used by Scandinavian traffic disdaining the convoy system (which routed them much further North) it was also routinely taken by warships. J6 lies nearby and the yet to be discovered cruiser HMS Nottingham will not be too far away. Needless to observe it was a hunting ground for U-boats.

Ships inbound along this time-honoured route branched off at various points depending upon their destination. Ships bound for the Tyne usually set a course from this axis to make landfall at St Mary’s Island, those heading for Blyth adopted a course for Coquet Light. Those vessels inbound from Norwegian waters usually selected a course to make landfall at St Abb’s Head or Longstone Light. The divers had little difficulty in identifying this wrecked submarine as a ‘G’ class boat. The stern section of the boat was missing but the bows were aligned South West, suggesting the boat in question was inbound and heading towards Coquet Island and the War Channel at the time of its loss. Two ‘G’ class boats were known to be missing in the North Sea. Maritime historians had of course long concluded that both G8 and G7 had been mined far away from home. Clearly this one had been destroyed on its own doorstep. The problem was identifying which boat it was ?

Both submarines were identical in pattern. No identification could be possible from the structural characteristics of the wreck. It might be thought that circumstantial evidence pointed to the wreck being G7 which after all had made its last patrol from Blyth and might reasonably have been expected to adopt a heading taking it towards Coquet Island. Unfortunately the Tees based boats engaged in patrols off Scandinavia also used this route, often entering the ‘War Channel’ at Coquet Island or Longstone before making their way South to the Tees. It is clear from information gleaned from earlier patrol logs that both G8 and G7 routinely used the Coquet Island track.

The mystery remained stubbornly unresolved until 2019 when the Thyboren Museum released news that a ‘G’ class submarine wreck had been discovered off Hirtshals Havn in Denmark. While both G8 and G7 had been sent to patrol off Denmark, only G8 had been ordered to patrol inside the Kattegat. This submarine, discovered in a position on G8‘s return route, could only be that submarine. The wrecked submarine had following a South Westerly course at the time of her loss.

An air of mystery continues to surround the demise of G8. The boat is shrouded in fishing nets but the bow is clearly pointing upwards on an acute angle and the hydroplanes are set for eternity at hard-a-rise. There is evidence that whatever overtook her, happened on the surface. There is no evidence of mine damage so what could happened ? There is always the possibility of a battery explosion such as the one which damaged E30, and killed three men in April 1916. See the Beach Cemetery, Blyth. Battery explosions usually resulted in localised damage and rarely caused the destruction of a submarine however.

Other potential causes are that she collided with an obstruction or was run down by a merchant or even a warship.  If either of these had been the case there would be extensive damage to both casing and pressure hull.  None has been reported. One plausible explanation is that that the boat may well have hit a patch of dense water while sailing trimmed down with only the conning tower above the surface (so producing a minimal target).  There are some good accounts by Second World War submariners who narrowly escaped being sunk in this fashion – see Ben Bryant ‘One man Band’.  If G8 suddenly entered a stretch of dense water (caused by melting ice) the boat would become heavy. Trim would be lost.  In the event of the conning tower or any other part of the boat where there was an open hatch, dipping below the surface, the boat would have been inundated. submariners called this ‘pooping’ and it is thought to have caused the loss of an ‘H’ boat during the Second World War.  In the First World War the phenomenon of heavy water was barely understood, submarine warfare being in its infancy.

The evidence points to a sudden, catastrophic plunge which could not be arrested using the hydroplanes. The trapped men had no means of exiting the stricken boat in a depth of one hundred feet. With no escape sets (Unlike the German Drager sets, considered as standard equipment in U-boats, no escape set was issued to British Submarines until the 1930’s with the introduction of Davis escape equipment or DSEA). Presumably the boat was trapped on the sea bed with men still alive within the control room at least.  They would have turned the hydroplanes to the hard-a-rise position and attempted to drive G8 to the surface via a combination of high pressure air harnessed to the power of the motors. The angle of the boat was likely the result of frantic attempts to blow reserve air tanks. In this scenario the crew of G8 slowly fell victim to carbon dioxide (see Untamed Unravelled) or chlorine gas in the end.

The discovery of G8 in a position along her anticipated return track from the Kattegat meant that the Farnes Deep submarine must, by a process of elimination, be G7. It will be recalled that G7 had been ordered to patrol Little Fisher Bank. Based upon analysis of previous ‘G’ class patrols in the Little Fisher Bank sector, it would have taken three days sailing from Blyth to reach this billet and a further three days to return.  The average length of patrol in this sector was six days.  It is probable that Lt. Russell left the billet on the night of October 27/28, following the same return route as that adopted on her previous patrol. Submariners of the period were creatures of habit. If a route proved to be safe and mine free it would be habitually adopted unless circumstances dictated otherwise. This course would have taken the returning G7 through 55° 31’N 0° 41’W, thence the Navigation Officer would have shaped a South Westerly course in the direction of Coquet Light.

The Blyth boats were required to transmit an ETA signal to Titania when five miles away from the War Channel to advise which approach – St Abbs Head, Longstone, Coquet Island or St Mary’s Island – was being used. In this instance the course was shaped towards Coquet Island as per previous patrols.  As no message was ever received from G7, the evidence is that she was destroyed on the surface in darkness before reaching the five mile point.

The adopted heading took G7 past the North East Banks and through the Farne Deeps where she met her fate. But what exactly was that fate ?

The wreck of G7 is not intact. While the forward section of the boat is remarkably well preserved, the stern section is missing. Damage of this nature usually points to a mine having been the cause of destruction. Moreover based upon the evidence of earlier patrol logs and the time of year, it is highly probable that the returning G7 crossed the Farnes Deep sector in darkness in the early hours of October 31 – All Hallows Eve. Judging from the local Auxiliary Patrol diary, there was poor visibility and a heavy swell. This adds weight to the mining theory. It was difficult to spot mines in the best of weather but in these conditions and in darkness, near impossible. What does the wreck tell us ? The hydroplanes are set at neutral and the (intact) conning tower hatch is open. The search periscope is in the housed position. This is firm evidence that the boat was on the surface when disaster overtook her

While the Germans laid no claims to having sunk any submarines during the time frame of G7‘s patrol, we do know that mines had been laid by U-boats off the Northumberland and Scottish coasts in the second half of 1918. On the evidence of Spindler’s ‘Handelskrieg‘, Band 5, two clear candidates emerge, UC-59 and U-78 . Let us now consider their missions.

On August 17, 1918 UC-59 (Oblt. G. Strasser) left Brunsbuttel for a patrol off the North East coast. On the night of August 22, mines were laid North of Longstone (Sperre 60). Next day Strasser went on to make a torpedo attack on a convoy of ten ships, sinking Auckland Castle with heavy loss of life. On August 27, UC-59 laid mines off St Abb’s Head (Sperre 61). By September 3, UC-59 was back at Brunsbuttel. The Longstone minefield was laid at 55° 41′ N but within 1°29′ 8. W. This minefield was designed to sink vessels sailing in the War Channel passing Eastwards of the Farne Islands. In other words the mines were laid too far inshore to have directly accounted for G7 in the Farne Deeps. It is therefore unlikely that field laid by UC-59 was responsible for sinking G7.

On September 22, U-78 (Oblt J. Vollbrecht) left Brunsbuttel to lay a minefield off the East coast (Sperre 67). Interestingly U-78 was one of the last survivors of the UE class of mine-laying U-boats, known to their crews as ‘The Children of Sorrow’ (See ‘UC-32 and The Children of Sorrow’).

The field laid by U-78 on the night of September 27, 1917 consisted of thirty-four mines (which had no time-setting) laid in an zig-zag-pattern from:

56°00’N-01°11’W
55°59’N-01°12’W
55°57’N-01°12’W
55°56’N-01°13’W
55°55’N-01°13’W
55°54’N-01°12’W

It is highly likely that these mine-laying expeditions were directly related to the German operation known to British naval intelligence as the ‘Bell Rock Arc’ previously described. These recent minefields constituted its Southern extension and Room 40 surmised that the next mine-lay would be between St Abbs Head and Blyth. Room 40 appears to have been tracking U-78′s mine-laying activities judging from the ‘Room 40 History’. This boat was specifically identified in relation to the ‘Bell Rock Arc’ operation. Certainly Room 40 was acting on  specific intelligence in directing Sector VIII mine-sweeping activities in October 1918, judging from the Tyne Diary, ADM 53/63732.  These mines were apparently ‘being swept as soon as they were laid‘ by mine-sweepers from Rosyth and South Shields. In fact time was running out for U-78 as an interesting post-script bears witness. Acting upon intelligence from Room 40, a trap was set. A British submarine would be sent to patrol around the exit from Weg Rot off the Danish coast.

U-78 did indeed leave on a mining patrol but her destination was not the North East coast of England. In fact orders were altered and the lumbering old mine-layer was ordered to plant mines off the Dutch coast. The Blyth submarine HMS G2 (Lt H. Lake) had earlier been dispatched following warnings by Room 40 to watch ‘Blue Route’ one of the regular exit courses used by High Seas Fleet U-boats. At 02:16 on October 28, G2 was surfaced at 56°02’N 05°08’E off Ringkobing. The telegraphist detected the sound of active oscillators suggesting an enemy vessel was sending a recognition signal. A large submarine hove into view through the darkness. G2 conned down. The torpedo tubes were brought to ready. Lake turned G2 bows-on to the approaching U-78. A failure in the voice-pipe valve between control room and torpedo chamber resulted in range closing to one thousand yards before the torpedoes were fired. The torpedo detonation was witnessed from the bridge of G2 as a white flash followed by thick billowing smoke. There were hundreds of dead fish around the site of the explosion, some German clothing but no survivors or bodies. G2 withdrew from the scene.

Returning to the fate of G7, all factors considered, the U-78 September field is too far North to have destroyed G7 as the most Southerly mines were laid off Coldingham in Berwickshire. It can be stated with confidence that no German minefield had been laid across the track of G7. One further possibility remains but before it is examined it is reasonable to state that she may not have been destroyed by a mine at all.

When a submarine or a ship has been mined the often jagged fragments surrounding the detonation point usually, but not always, curve inwards.
I have spoken to divers who have examined the wreck of G7 who say this kind of damage is conspicuously absent from the wreck of G7. The divers in question are familiar with mine-destroyed U-boats. The break is more of a shear.  Fittings have been sliced through.  Part of the port side hydroplane is there with its massive guard but the rest is missing and the thick steel guard has been cleaved away. The break is clean. The stern section is nowhere to be seen. Sidescan sonar suggests that it lies fifty metres from the main section of the boat. A mine could conceivably do that.  So could the bows of a ship. 

A prize bounty was paid to any merchant ship which could prove it had sunk at U-boat. This factor led to the destruction of HMS/M H5 and her fine crew in March 1918. It was also responsible for a spate of friendly fire incidents launched against Blyth submarines mistaken for U-boats from 1916 to the end of the War. As has been noted, the Longstone/Lista route and its variants was routinely used by ships sailing for the Skaggerak and Kattegat as well as Norway. No ramming incident was notified to naval intelligence (NID) during this period. The Tyne Auxiliary Patrol Diary likewise has no records of any U-boat encounters. However it is questionable whether the crew of a merchant vessel, having rammed a British submarine in the mistaken belief it was a U-boat, upon realising their error, would have informed the authorities.

There is some evidence that traffic on this route was particularly heavy during the time in which G7 must have made her return journey. The Germans ceased their Handelskrieg or war against shipping on October 20. In the ten days which followed, neutral merchant vessels were eschewing the OZ Norwegian convoy system in favour of direct and quicker voyages across the North Sea according to the Tyne Diary. In this scenario it is not difficult to envisage a situation in which G7 may have been accidentally or for that matter, deliberately rammed. The submarine would have sailed without lights until she entered the War Channel. Although the Handelskrieg had been called off, it is likely that merchant vessels would have been very cautious during the North Sea crossing at this time and may not have displayed lights themselves. The possibilities of darkened ship and submarine occupying the same channel colliding are, in my opinion, significant. One further possible cause of loss emerges from research.

The Leith Lockhart Mining History is the primary document detailing the British minefields laid in the First World War. Despite intense U-boat activity off the North East coast, no protective minefield was laid until the Summer of 1918. The Leith Lockhart History describes how work commenced on the East Coast Barrage from July 26, 1918. The mines were laid from the Humber to a position running NNE from the Tyne along the track of Tyne No. 2 Channel which was subsequently abolished. The work was carried out in September by ships from the 1st Minelaying Squadron. In early October the field was extended to the North ‘to within eight miles of the centre of Tyne No. One Channel’

The Northern extension of the East Coast Barrage was supposed to provide a protective flank for the Blyth submarines but it is not too difficult to see how it could also pose a deadly hazard should any of the mines break loose from their moorings to end up in ‘M’ channel or the Coquet Island route. From records it is known that October 30-31 was characterised by strong offshore winds and heavy seas. Such conditions may well have caused some of these newly laid mines to break free from their moorings and drift the short distance to foul the Farnes Deep sector. In this scenario G7 may well have ironically fallen victim to a British mine.

Two Sector VIII Auxiliary Patrol trawlers scoured the inner end of the Coquet Island/Lista route very close to the position of the G7 wreck on 28 and 30 October. Both trawlers reported the sector clear of mines but of course a mine would not necessarily be visible in difficult conditions and any loose mines could have exploded by this stage.

G7 clasps her secrets close. We can never know for certain what destroyed her or even precisely when she was lost but on the basis of her three previous patrols and the available evidence, a strong case can be made for G7 having completed her patrol off Little Fisher Bank on the night of October 27/28. The boat followed the same inbound track as that taken in her previous patrol (given in the patrol summary above). G7 adopted the Coquet Island route through the Farnes Deep. In the early hours of 30/31 October, in total darkness, the balance of probability is that the surfaced G7 detonated a loose British mine which blew her stern off. The boat would have gone down by the stern in minutes, taking most of those onboard with her. Two or three men on watch on the conning tower may have been flung into the sea but would have stood no chance of survival. Their bodies may have drifted out to sea. I have been unable to find any ‘unknowns’ washed ashore locally during the critical time line but this in itself is not conclusive. If any men did manage to close watertight doors in the control room or fore-ends, boats of this period were not fitted with escape equipment or provided with breathing sets, unlike their German counterparts. The fact that the conning tower hatch is open is probably due to the sudden overwhelming explosion rather than an attempted escape.

Submarining was and remains a dangerous game. For the most part the 11th Submarine Flotilla had been spared the heavy losses destined to be suffered by its successor, the 6th Submarine Flotilla in the Second World War. Nevertheless there is something particularly tragic about a submarine lost while inbound having likely detonated a British mine on the very threshold of safety in literally the last two weeks of the War. All that can be stated with certainty is that G7 holds the grim distinction of being the last British Submarine lost in the First World War.

The Crew of HMS/M G7

RESURGAM !

G7‘s October log has not survived
ADM 173/2378,
ADM 53/63732,
ADM 173/2424. ADM 137/871

Leith Lockhart ‘Mining History’, Spindler ‘Handelskrieg mit U-booten’ Band 5

APPENDIX HMS/M G7

Date of Loss: October 29-31, 1918

Location: The Farnes Deep

Depth: 92m

Type: ‘G’ Class Overseas submarine Builders: Armstrong Whitworth and Co, Elswick, Tyne Ordered: July 1914 emergency war programme

Keel laid:8.12.14 . Yard No: 881Launched: 4.3.16

Completed: 19.8.16 at High Walker Yard on Tyne

Technical specifications:

Hull: Double Surface displacement: 703 tons U/Dt: 837 tons LBDH: 57m x 6. 86m x 4.11m Machinery: 2 x Vickers Admiralty 800hp diesel engines Props: 2 bronze S/Sp: 15.5k underwater speed: 9k (design speed)

Op/R: 2,400 nautical miles at 12k Sub/R: U/Power: 2 x 420hp electric motors at 10k Batteries: Exide lead/acid Fuel/Cap: 44 tons

Armament: 5 x (2 x 45.72cm (18″) bow torpedo tubes, 2 x 18″ ‘midships tubes, 1 x 53.34cm (21″) stern tube. 10 Torpedoes carried.

Guns: 1 x 76mm (3″) Quick firing gun on retractable mount, one 2 pounder on aft end of bridge

Complement: 3 officers and 27 ratings

Diving: 100 -150′ but designed for 200′

Service: G7 served with the 10th Submarine Flotilla, Depot ship HMS Lucia at Eston on the River Tees, joining in late August 1916. G7 served in support of Grand Fleet activities. Her commanders were:

Lt. Samuel Gravener 1 April, 1916- 1 June 1916,

Lt. Cdr. Geoffrey Warburton, 15 May 1916 – 14 November, 1917

Lt. Maurice Bailward 14 November 1917 – 21 November, 1917

Lt. P. Stanley November 1917 – 2 September, 1918

Lt. Charles Russell, Officer in Command from 2 September to the time of her loss in October 1918.

On September 2, 1918, G7 was attached to the 11th Flotilla at Blyth to counter an expected German incursion off the East Coast. The boat carried out three patrols from Blyth.

Patrol One: 9.9.18 – 17.9.18 Little Fisher Bank Coded ‘R Patrol’

Patrol Two: 28.9.18 – 7.10.18 SW of Lister Light, South coast of Norway, Coded ‘Z21 Patrol’

Patrol Three: 21.10.18. Boat failed to return from a patrol off Little Fisher Bank. Crew recorded as Discharged Dead on November 1, 1918.

© P Armstrong