Hypothetical: The British detect Bismarck with a ship-borne Walrus at 0900 on 25 May 1941.

[Michael L]

I invite Forum Members to consider the ‘what if’, or ‘what might have been’ of a Walrus detecting the Bismarck circa 0900 on 25 May 1941. This is based on Admiral Tovey’s Despatch/Report of 5 July 1941:

48. The enemy's courses west of south were being covered by SUFFOLK and, to a lesser extent, by NORFOLK and PRINCE OF WALES. KING GEORGE V worked across to the south-westward to cover a southerly course, allowing for an increase of speed by the enemy. Consideration was given to flying off the Walrus from KING GEORGE V to search the perimeter astern of the ship and so cover a south-easterly course of the enemy; but the swell was such that the sacrifice of the aircraft would almost certainly result, and I did not wish to expose KING GEORGE V to U-boat attack whilst picking up the crew. Subsequent analysis shows that such a search might possibly have located the BISMARCK.

By way of setting the scene:

25th – At 0013 hours the CinC Home Fleet signalled to RA 1CS in NORFOLK that he hoped to engage the BISMARCK, with KING GEORGE V and REPULSE at about 0900/25/5/41, which was about Sunrise, from the eastward. The CinC then signalled REPULSE, who’s armour was inferior to the HOOD’s, that in the engagement she was to keep 5000 yards outside of him and not to engage until KING GEORGE V had opened fire.
At 0306 hours the SUFFOLK lost contact with BISMARCK, but didn’t immediately report the loss of contact. Contact was lost because BISMARCK turned on to a south easterly course.
At 0401 hours SUFFOLK reported the loss of contact.
At 0600 hours, the CinC Home Fleet working on the assumption that BISMARCK was still steering southerly, continued steering south westerly in KING GEORGE V with REPULSE, crossed ahead the new track of the BISMARCK who was now steering south easterly, at about 100 miles ahead of BISMARCK.
https://www.naval-history.net/xGM-Chron ... orge_V.htm

If Tovey had launched HMS KGV’s and/or HMS Repulse’s Walrus, they may have detected Bismarck say, circa 0900 25 May (allowing for sunrise).

PoW (75% effective), Norfolk and Suffolk would have been to the South-West were they were searching, around two hours away.
HMS Rodney (max speed 21 kts) and its three destroyers were to the East, around two hours away.
HMS Ramillies (max speed 21 kts)) was to the South, around four hours away.
HMS Victorious and its four light cruisers were around four hours to the north, with 9 Swordfish and 4 Fulmars.
Note, HMS Repulse was close to its fuel limit;- i.e.

At 1000 hours in approximate position 54N, 36W REPULSE, who was short of fuel, detached for Conception Bay, Newfoundland. Because of shortage of fuel REPULSE could only steam at 8 to 10 knots. https://www.naval-history.net/xGM-Chron ... epulse.htm

And Bismarck, while slightly damaged, was still capable of manoeuvring with a max speed of at least 27 kts.

The above estimates are based on the following from Admiral Tovey’s Despatch/Report:

33. KING GEORGE V and REPULSE steered an intercepting course with the object of bringing the enemy to action soon after sunrise with the sun low behind us. The situation at this time was as follows: —
(a) The enemy appeared to have settled down to a-course of 180° at about 22-24 knots. They were, for no apparent reason, zig-zagging. They were shadowed by SUFFOLK from astern and by PRINCE OF WALES and NORFOLK from the port quarter. The BISMARCK had suffered some damage but retained her fighting efficiency, though an aircraft had reported that she was leaving an oil wake. Their reduced speed was probably dictated by the need for economy of fuel and to afford an opportunity of breaking contact (by an increase of speed after dark. PRINCE OF WALES had two guns out of action and considerable damage to her bridge.
(b) KING GEORGE V and REPULSE were closing from the eastward and would, if the enemy held their course, make contact about 0830, half an hour after sunrise. REPULSE was short of fuel, but had just enough to fight a short action and then reach Newfoundland. By midnight all destroyers had left for Reykjavik to fuel.
(c) RODNEY (Captain Frederick H.G. Dalrymple-Hamilton), with three destroyers, was approaching from the south-eastward and would join about 1000.
(d) RAMILLIES '(Captain Arthur D. Read) was approaching from the south, steering to get to the westward of the enemy, and would make contact about 1100.

And.

49. The Rear-Admiral Commanding, Second Cruiser Squadron, was ordered by signal to organise an air and surface search, with VICTORIOUS and his four cruisers, north-west of the last known position of the enemy. When I issued these instructions, I estimated that the Rear-Admiral Commanding, Second Cruiser Squadron, and VICTORIOUS were well to the northward of this position; but in point of fact he had been steaming south at high speed and was now close to it.

The ‘what if’, or ‘what might have been’ of a Walrus detecting the Bismarck circa 0900 is, IMHO, based on the historical evidence, a plausible scenario.

The questions that I now submit for discussion are:
On receipt of a radio signal from a Walrus circa 0900 on 25 May, what do Forum Members think Admiral Tovey’s tactics would have been to deal with the Bismarck?
And
What would Admiral Lutjens' response have been?

[paul.mercer]

It's a lot of question!
Bismarck was doomed from the moment her rudder was jammed, if she was supposedly zig-zagging and losing oil, but was in fact was turning in a circle, it would infer that her rudder had already damaged by the swordfish torpedoes, so with all those RN ships converging on Bismarck, in reality Lutyens did not have any options but to fight it out, he knew it and so did his crew.

[Michael L]

I disagree. This hypothetical (25 May) predates Bismarck's rudder being being jammed by the Ark Royal's Swordfish attack.

This is how I see it. The paragraph 33 of Admiral Tovey's Despatch/Report implies that he had developed a plan of engagement based on Bismarck continuing on a southerly (180 degrees) track.

KING GEORGE V and REPULSE were closing from the eastward and would, if the enemy held their course, make contact about 0830, half an hour after sunrise. REPULSE was short of fuel, but had just enough to fight a short action and then reach Newfoundland.

This suggests that, Admiral Tovey intended to engage with KGV and Repulse, presumably also with PoW, Norfolk and Suffolk. But Repulse could not be relied upon for a ‘long engagement’.

I submit that if Bismarck’s southerly course had continued, Lutjens is likely to have ‘run’ south. Keeping ahead of the British Ships with some hope he might be able to shake them off at night. And some knowledge that the British would have to break off due to fuel shortages.

With the Walrus sighting scenario as outlined, Tovey was now in the situation of having to shortly release Repulse and try and link up with PoW, Norfolk and Suffolk. I suspect he could have tried to shadow Bismarck with KGV – having still released Repulse - while he waited for PoW, Norfolk and Suffolk to catch up. Following Bismarck to the East toward Brest, and toward Rodney, the three destroyers and Edinburgh. Tovey could have tasked Victorious to launch Swordfish to attack Bismarck.

Tovey’s dilemma would then have been that PoW and Suffolk were getting low on fuel. Norfolk could have kept up with KGV. But Rodney was too slow. The three destroyers may have been of valuable assistance, particularly at night. And Force H was still some distance off.

So, for me it comes down to if Tovey would have taken on Bismarck with just KGV and Repulse around noon on 25 May? I think that he would have, in the true Royal Navy tradition, given battle. He would have trusted in KGV taking on Bismarck with Repulse, as ordered, “5000 yards outside of him and not to engage until KING GEORGE V had opened fire”. I feel that Tovey would have trusted that he would get the better of Bismarck, or at least caused more damage to Bismarck making it easier for the rest of the Fleet to deal with Bismarck later.

The question then is would Lutjens have engaged in battle, or would he have steered south and tried to get away, fighting a running battle. I don’t know. But I suspect Lutjens would initially have steer a southerly course mindful of the fleet order to avoid unnecessary fighting with enemy capital ships. Keeping ahead of the British Ships with some hope he might be able to shake them off at night. And some knowledge that the British would have to break off due to their fuel shortages.
Of course, Lutjens' problem was his own fuel supplies. Turn east again at some stage and make for France? Or try and rendezvous with an oiler in the mid-Atlantic?

[dunmunro]

The situation at 0800 25 May (Battle Summary 5):

May25_0306.jpg

(202.16 KiB) Not downloaded yet

[paul.mercer]

Hi Michael,
Sorry about the first post, I had assumed that Bismarck had already been crippled.
Re the rest you posted:
b) KING GEORGE V and REPULSE were closing from the eastward and would, if the enemy held their course, make contact about 0830, half an hour after sunrise. REPULSE was short of fuel, but had just enough to fight a short action and then reach Newfoundland. By midnight all destroyers had left for Reykjavik to fuel.
(c) RODNEY (Captain Frederick H.G. Dalrymple-Hamilton), with three destroyers, was approaching from the south-eastward and would join about 1000.
(d) RAMILLIES '(Captain Arthur D. Read) was approaching from the south, steering to get to the westward of the enemy, and would make contact about 1100.
It is an interesting scenario.
I suppose it all depends on what you call a 'short action' by Repulse, if she and KGV could have held on to Bismarck for an hour and a half (until 10am) then Rodney would have come in to the battle. Even if Repulse did disengage earlier I suppose we could hope that in the short time of action between 8 x15" (Bismarck) and 10x 14" + 6 x15" KG & Repulse, which hopefully would survive) sufficient damage would have been done to Bismarck to slow her up until Rodney and perhaps Ramillies arrived on the scene and join KG in shooting her to bits.
Personally I think Lutyens would have avoided battle and still made a run for Brest as Repulse was the only ship fast enough to catch Bismarck, but she didn't have the fuel or the firepower to take her on by herself.
The facts are that had Bismarck not taken a hit in her rudder I don't think any of the RN ships would have got near her

[Michael L]

Hi Paul.
I think you have identified one of the crtical issues, namely, slowing the Bismarck down.
This was Tovey's problem when he was chasing Bismarck historically. And Ark Royal and it's Swordfish delivered.
Could KGV and Repulse slow the Bismarck down in a 'short action'?

I feel another critical issue is the British ships running short of fuel. For Admiral Tovey this would have presented him with some hard decisions. Would Admiral Tovey have immediately given battle with KGV and Repulse, like Admiral Holland did with PoW and Hood two days earlier. This would be very much in the Royal Navy’s tradition.
However, Repulse was running on empty:

At 1000 hours in approximate position 54N, 36W REPULSE, who was short of fuel, detached for Conception Bay, Newfoundland. Because of shortage of fuel REPULSE could only steam at 8 to 10 knots. https://www.naval-history.net/xGM-Chron ... epulse.htm

‘The Grand Alliance’ (1950) has the following entry.

Fuel was a grave anxiety, and Admiral Tovey had decided that unless the Bismarck’s speed could be greatly reduced he would have to abandon the chase at midnight. I suggested to the First Sea Lord, and he signalled accordingly, that he should be towed home if necessary, but by then it was known that the Bismarck was actually steaming in the wrong direction. Her main armament was uninjured, and Admiral Tovey had decided to bring her to battle in the morning [of May 27th].

Admiral Stephen Roskill criticized the ‘towing’ idea in his ‘Churchill and the Admirals’ (1977):

In May 1941 Tovey’s fleet, and many other ships, were involved in the dramatic pursuit of the Bismarck….When it seemed that Tovey’s two battleships (King George V and Rodney) might be forced to break off the pursuit because of shortage of fuel he [Churchill] came up with one of the most extraordinary signals of the war—“Bismarck must be sunk at all costs and if to do this it is necessary for King George V to remain on the scene she must do so even if it subsequently means towing King George V.” It should be noted that, although this signal was sent by [First Sea Lord Dudley] Pound, Churchill himself admits that he originated it which shows how the former sometimes acted as mouthpiece for the latter. After Tovey had returned to harbour Pound apologized to him for the despatch of this signal; but he surely should not have allowed it to be sent.

I seriously doubt that any Royal Navy Captain would allow his ship to run out of fuel. There are many examples of Captains cutting it fine, that is arriving back in port with only a few tons of fuel left in their Ship’s tanks. I do not know of any RN Captain running out of fuel, Can a Forum Member cite an example?

I submit that it has been shown that Admiral Tovey was not prepared to let the KGV run out of fuel. And that he was prepared to ‘abandon the chase’. British Captains had only one option, to return to port.

Admiral Lutjens had previously been out in the Atlantic with the Scharnhorst and Gneisenau, Operation Berlin – Atlantic Raid 22 January to 22 March 1941. He was well aware of how he had two options. Go back to port, or rendezvous with a German Tanker in the vastness of the Atlantic Ocean.

Wikipedia

KGV
5,400 nmi (10,000 km) at 18 knots (33 km/h).
Bismarck
8,525 nmi (15,788 km; 9,810 mi) at 19 knots (35 km/h).

There is a 2021 Post on this Forum, “Bismarck range”, that explores the issue of range.
Suffice to say, the general consensus is that the Bismarck had greater range and endurance than the KGV class.

Could KGV and Repulse slow the Bismarck down in a 'short action'?
If on spotting the KGV and Repulse Lutjens decided to conduct a running fight (as per his orders), that is Bismarck sailing on a southerly course, again, ahead of the pursuing KGV and Repulse, then we are talking a Bismarck stern 4x15 vs a British bow 6x14 and 4x15 (with Repulse to the rear).
In this situation, I respectfully submit that Tovey could not have sustained such a pursuit for more than an hour before Repulse would have to break-off low on fuel. Unless the British scored a decisive hit(s) that slowed Bismarck to at least 20kts, I submit that Tovey would have abandoned the pursuit.

Kind regards, Michael L.

[dunmunro]

Hi Paul.
I think you have identified one of the crtical issues, namely, slowing the Bismarck down.
This was Tovey's problem when he was chasing Bismarck historically. And Ark Royal and it's Swordfish delivered.
Could KGV and Repulse slow the Bismarck down in a 'short action'?

I feel another critical issue is the British ships running short of fuel. For Admiral Tovey this would have presented him with some hard decisions. Would Admiral Tovey have immediately given battle with KGV and Repulse, like Admiral Holland did with PoW and Hood two days earlier. This would be very much in the Royal Navy’s tradition.
However, Repulse was running on empty:

At 1000 hours in approximate position 54N, 36W REPULSE, who was short of fuel, detached for Conception Bay, Newfoundland. Because of shortage of fuel REPULSE could only steam at 8 to 10 knots. https://www.naval-history.net/xGM-Chron ... epulse.htm

‘The Grand Alliance’ (1950) has the following entry.

Fuel was a grave anxiety, and Admiral Tovey had decided that unless the Bismarck’s speed could be greatly reduced he would have to abandon the chase at midnight. I suggested to the First Sea Lord, and he signalled accordingly, that he should be towed home if necessary, but by then it was known that the Bismarck was actually steaming in the wrong direction. Her main armament was uninjured, and Admiral Tovey had decided to bring her to battle in the morning [of May 27th].

Admiral Stephen Roskill criticized the ‘towing’ idea in his ‘Churchill and the Admirals’ (1977):

In May 1941 Tovey’s fleet, and many other ships, were involved in the dramatic pursuit of the Bismarck….When it seemed that Tovey’s two battleships (King George V and Rodney) might be forced to break off the pursuit because of shortage of fuel he [Churchill] came up with one of the most extraordinary signals of the war—“Bismarck must be sunk at all costs and if to do this it is necessary for King George V to remain on the scene she must do so even if it subsequently means towing King George V.” It should be noted that, although this signal was sent by [First Sea Lord Dudley] Pound, Churchill himself admits that he originated it which shows how the former sometimes acted as mouthpiece for the latter. After Tovey had returned to harbour Pound apologized to him for the despatch of this signal; but he surely should not have allowed it to be sent.

I seriously doubt that any Royal Navy Captain would allow his ship to run out of fuel. There are many examples of Captains cutting it fine, that is arriving back in port with only a few tons of fuel left in their Ship’s tanks. I do not know of any RN Captain running out of fuel, Can a Forum Member cite an example?

I submit that it has been shown that Admiral Tovey was not prepared to let the KGV run out of fuel. And that he was prepared to ‘abandon the chase’. British Captains had only one option, to return to port.

Admiral Lutjens had previously been out in the Atlantic with the Scharnhorst and Gneisenau, Operation Berlin – Atlantic Raid 22 January to 22 March 1941. He was well aware of how he had two options. Go back to port, or rendezvous with a German Tanker in the vastness of the Atlantic Ocean.

Wikipedia

KGV
5,400 nmi (10,000 km) at 18 knots (33 km/h).
Bismarck
8,525 nmi (15,788 km; 9,810 mi) at 19 knots (35 km/h).

There is a 2021 Post on this Forum, “Bismarck range”, that explores the issue of range.
Suffice to say, the general consensus is that the Bismarck had greater range and endurance than the KGV class.

Could KGV and Repulse slow the Bismarck down in a 'short action'?
If on spotting the KGV and Repulse Lutjens decided to conduct a running fight (as per his orders), that is Bismarck sailing on a southerly course, again, ahead of the pursuing KGV and Repulse, then we are talking a Bismarck stern 4x15 vs a British bow 6x14 and 4x15 (with Repulse to the rear).
In this situation, I respectfully submit that Tovey could not have sustained such a pursuit for more than an hour before Repulse would have to break-off low on fuel. Unless the British scored a decisive hit(s) that slowed Bismarck to at least 20kts, I submit that Tovey would have abandoned the pursuit.

Kind regards, Michael L.

The RN had made provisions for RN ships including KGV to refuel via oilers in Eire, this would have given KGV several humdred more NM of range. Additionally the RN had sent out a number of oilers to potentially refuel RN ships at sea:

http://www.kbismarck.org/forum/viewtopi ... ler#p83493

[Michael L]

I stand corrected on a technicality. While I concede that the RN had ‘Tankers’ from the outbreak of the Second World War, they were far from proficient in the practice of replenishment at sea (RAS) for some time. I respectfully submit that it was not until 1942 that the practice of RAS in the Atlantic and Arctic for convoy escorts was routinely conducted. [See British Journal for Military History, Volume 8, Issue 3, November 2022, The Royal Fleet Auxiliary and Post-War Change, by George Wilton. https://bjmh.gold.ac.uk/article/download/1648/1762 ]

Also, I have not found a historical example of a RN capital ship or cruiser conducting an operational RAS (as opposed to a training exercise) prior to 1942.

With respect to the cited message sent by V.C.N.S., 2030B/24 to C. in C. H.F., CO Force H., etc, etc.:

24.5.1941
Oilers Disposition
1 (a) Oiler CAIRNDALE fitted for oiling at sea, and with scuttling charges has been sailed from Gibraltar to patrol on a line 60 miles 225° from 43° 35°.
1 (b) Severn will escort CAIRNDALE who is expected to reach the patrol line about 31/5.
2. Oiler is being sent to St. Johns, N.F. Capital ships can be fuelled in emergency from oiler in Concepcion Bay.
3. There are tankers in convoys HX 187 and 128 with fuel oil.
4. Enquiries are being made whether any U.S. oiler facilities can be made available.
5. Oiler SAN ADOLFO has been ordered to patrol a line 60 miles 225° from position 39° 49°. She should reach this position about 28/5.
6. Attention is drawn to Chart of Sea Surface Conditions for May Y 185 recently issued.
http://www.kbismarck.org/forum/viewtopi ... ler#p83493
http://www.kbismarck.org/forum/viewtopic.php?t=8265

With respect to paragraph 1. IIRC this oiler disposition was to support Force H. Also, I question the accuracy of the Lat 43°, Long 35° (transcript error?).
With respect to paragraph 2. IIRC it was this static oiler at Conception Bay, NF, that HMS Repulse was directed to.
With respect to paragraph 3. Convoy HX187 sailed in 1942. Assuming a transcript error, Convoys HX 127 & 128 did have tankers in them. I question whether they were equipped and trained to do RAS. I also question if Admiral Tovey would have gone looking for one of these Convoys in order to conduct KGV RAS.
With respect to paragraph 4. At this stage of the War, I consider it unlikely the Americans (USN) would have offered a Tanker. Besides, as this signal is dated 24 May, a USN Tanker would not have arrived in time.
With respect to paragraph 5. The Tanker San Adolfo would not reach the position till 28 May. I have also plotted Lat 39°, Long 49° and do not consider its location to be a realistic option for Admiral Tovey and KGV.

While the cited signal shows the dispositions of Tankers, apart from the static Tanker in Conception Bay which Repulse was direct to, I do not consider that Admiral Tovey would have used any of the other options.

With respect to the following assertion:

The RN had made provisions for RN ships including KGV to refuel via oilers in Eire, this would have given KGV several hundred more NM of range.

I respectfully submit that this could have given more range. However, Admiral Tovey gave no indication that he seriously considered refuelling from a Tanker off Eire. On the contrary, Admiral Tovey was very conscious of the KGV being the only serviceable modern British RN Battleship and the need to preserve it by returning to a UK port.

The best evidence I can provide are Admiral Tovey’s own words, from his Despatch/Report dated 5 July 1941:

Fuel.
64. The shortage of fuel in the Home Fleet battleships was a matter of grave anxiety; KING GEORGE V had only 32 per cent, remaining, and RODNEY reported that she would have to part company at 0800 the next morning.
…
There were known to be several U-boats in the area and it was safe to assume that every available destroyer and U-boat in -the ports of Western Admiralty had also warned me to expect heavy air attack. It was therefore essential to allow a sufficient reserve of fuel to enable the battleships to return to United Kingdom ports at a reasonably high speed. The loss of HOOD and the damage to PRINCE OF WALES had left KING GEORGE V as the only effective capital ship remaining in Home Waters. I was not prepared to expose her unscreened at low speed to almost certain attack by U-boats unless there was very good prospect of achieving a result commensurate with the risk. I therefore decided that unless the enemy's speed had been reduced, KING GEORGE V should return at 2400 on 26th May to refuel.
65. The speed of KING GEORGE V was reduced to 22 knots at 1705 on 26th May to economise fuel and RODNEY, who had by then been overhauled, was formed astern.

So, although I concede that technically the RN had Tankers, at this time in the War I have found no evidence of any RN capital ships or cruisers conducting an operational RAS. I also seriously question if Admiral Tovey would have risked conducting an operational RAS with the KGV, given his concerns regarding U-boats, and his own conviction that with “the damage to PRINCE OF WALES had left KING GEORGE V as the only effective capital ship remaining in Home Waters.”

Kind regards, Michael L.

[Steve Crandell]

He didn't consider Rodney and Nelson to be modern?

[dunmunro]

I stand corrected on a technicality. While I concede that the RN had ‘Tankers’ from the outbreak of the Second World War, they were far from proficient in the practice of replenishment at sea (RAS) for some time. I respectfully submit that it was not until 1942 that the practice of RAS in the Atlantic and Arctic for convoy escorts was routinely conducted. [See British Journal for Military History, Volume 8, Issue 3, November 2022, The Royal Fleet Auxiliary and Post-War Change, by George Wilton. https://bjmh.gold.ac.uk/article/download/1648/1762 ]

Also, I have not found a historical example of a RN capital ship or cruiser conducting an operational RAS (as opposed to a training exercise) prior to 1942.

With respect to the cited message sent by V.C.N.S., 2030B/24 to C. in C. H.F., CO Force H., etc, etc.:

24.5.1941
Oilers Disposition
1 (a) Oiler CAIRNDALE fitted for oiling at sea, and with scuttling charges has been sailed from Gibraltar to patrol on a line 60 miles 225° from 43° 35°.
1 (b) Severn will escort CAIRNDALE who is expected to reach the patrol line about 31/5.
2. Oiler is being sent to St. Johns, N.F. Capital ships can be fuelled in emergency from oiler in Concepcion Bay.
3. There are tankers in convoys HX 187 and 128 with fuel oil.
4. Enquiries are being made whether any U.S. oiler facilities can be made available.
5. Oiler SAN ADOLFO has been ordered to patrol a line 60 miles 225° from position 39° 49°. She should reach this position about 28/5.
6. Attention is drawn to Chart of Sea Surface Conditions for May Y 185 recently issued.
http://www.kbismarck.org/forum/viewtopi ... ler#p83493
http://www.kbismarck.org/forum/viewtopic.php?t=8265

With respect to paragraph 1. IIRC this oiler disposition was to support Force H. Also, I question the accuracy of the Lat 43°, Long 35° (transcript error?).
With respect to paragraph 2. IIRC it was this static oiler at Conception Bay, NF, that HMS Repulse was directed to.
With respect to paragraph 3. Convoy HX187 sailed in 1942. Assuming a transcript error, Convoys HX 127 & 128 did have tankers in them. I question whether they were equipped and trained to do RAS. I also question if Admiral Tovey would have gone looking for one of these Convoys in order to conduct KGV RAS.
With respect to paragraph 4. At this stage of the War, I consider it unlikely the Americans (USN) would have offered a Tanker. Besides, as this signal is dated 24 May, a USN Tanker would not have arrived in time.
With respect to paragraph 5. The Tanker San Adolfo would not reach the position till 28 May. I have also plotted Lat 39°, Long 49° and do not consider its location to be a realistic option for Admiral Tovey and KGV.

While the cited signal shows the dispositions of Tankers, apart from the static Tanker in Conception Bay which Repulse was direct to, I do not consider that Admiral Tovey would have used any of the other options.

With respect to the following assertion:

The RN had made provisions for RN ships including KGV to refuel via oilers in Eire, this would have given KGV several hundred more NM of range.

I respectfully submit that this could have given more range. However, Admiral Tovey gave no indication that he seriously considered refuelling from a Tanker off Eire. On the contrary, Admiral Tovey was very conscious of the KGV being the only serviceable modern British RN Battleship and the need to preserve it by returning to a UK port.

The best evidence I can provide are Admiral Tovey’s own words, from his Despatch/Report dated 5 July 1941:

Fuel.
64. The shortage of fuel in the Home Fleet battleships was a matter of grave anxiety; KING GEORGE V had only 32 per cent, remaining, and RODNEY reported that she would have to part company at 0800 the next morning.
…
There were known to be several U-boats in the area and it was safe to assume that every available destroyer and U-boat in -the ports of Western Admiralty had also warned me to expect heavy air attack. It was therefore essential to allow a sufficient reserve of fuel to enable the battleships to return to United Kingdom ports at a reasonably high speed. The loss of HOOD and the damage to PRINCE OF WALES had left KING GEORGE V as the only effective capital ship remaining in Home Waters. I was not prepared to expose her unscreened at low speed to almost certain attack by U-boats unless there was very good prospect of achieving a result commensurate with the risk. I therefore decided that unless the enemy's speed had been reduced, KING GEORGE V should return at 2400 on 26th May to refuel.
65. The speed of KING GEORGE V was reduced to 22 knots at 1705 on 26th May to economise fuel and RODNEY, who had by then been overhauled, was formed astern.

So, although I concede that technically the RN had Tankers, at this time in the War I have found no evidence of any RN capital ships or cruisers conducting an operational RAS. I also seriously question if Admiral Tovey would have risked conducting an operational RAS with the KGV, given his concerns regarding U-boats, and his own conviction that with “the damage to PRINCE OF WALES had left KING GEORGE V as the only effective capital ship remaining in Home Waters.”

Kind regards, Michael L.

The Oiler destinations are patrol lines, not a single position.

The Admiralty war diaries supersede your opinions, sorry to be harsh, but that's how things work in the study of history. When you are presented with factual information from a new source that was probably unavailable to secondary sources, you need to pause and consider it's implications.

Tovey: "I therefore decided that unless the enemy's speed had been reduced, KING GEORGE V should return at 2400 on 26th May to refuel." But Tovey actually waited until ~1020/27 to return to the UK and KGV actually stopped in Northern Ireland, but didn't refuel until reaching Scotland: "Loch Ewe at 1230 on 29th May". So KGV, obviously, wasn't critically low on fuel upon reaching the vicinity of Northern Ireland.

Tovey probably didn't mention the possibility of refueling in Eire, IMHO, because the despatch was a public document and disclosure of sensitive matters regarding Eire would have caused diplomatic issues for both the UK and Eire governments.

The RN practised RAS between the wars and RAS was used to refuel RN destroyers during the battle for Crete:

16th - At 0530 hours in approximate position 35-30N, 22-30E, the QUEEN ELIZABETH, BARHAM, PERTH, NAIAD and the destroyers JERVIS, JAGUAR, GREYHOUND, HASTY, NIZAM, DEFENDER and IMPERIAL divided into Force A and Force D.

Force A comprised the QUEEN ELIZABETH, BARHAM, and the destroyers JERVIS, JAGUAR, NIZAM, DEFENDER and IMPERIAL and they were deployed to patrol to the west of Crete to provide cover against an attack by the Italian Fleet.

Force D comprised the PERTH, NAIAD and the destroyers GREYHOUND and HASTY and they were deployed patrolling between the islands of Antikythira and Milos to intercept any attempted seaborne invasion force.

At approximately 0700 hours Force A was joined by the destroyer ILEX from Alexandra.

At approximately 1200 hours Force A was joined by Force B comprising the light cruisers GLOUCESTER and FIJI and the destroyers HAVOCK and HOTSPUR.



(The GLOUCESTER and FIJI had joined from Heraklion where over night they had disembarked troops of the 2nd Battalion the Leicestershire Regiment. They had sailed from Heraklion at 0545/16/5/41)



During the afternoon the ten destroyers of Force A, B and C were refuelled from the QUEEN ELIZABETH and BARHAM.
https://www.naval-history.net/xGM-Chron ... zabeth.htm

From Battle Summary 4 (Crete): '

Early on the 16th, Vice-Admiral Pridham-Wippell was joined by the Ilex, and later in the day by Force “ B ”, consisting of the cruisers Gloucester (Captain H. A. Rowley, Senior Officer), and Fiji and destroyers Hotspur and Havock, which had landed reinforcements at Suda the previous night. During the day the destroyers with Force “ A ” were fuelled from the Queen Elizabeth,(5)
(5)Between the 16th and 19th May, 1,069 tons of oil were supplied by the Queen Elizabeth and 220 tons by the Barham to the 10 destroyers with Force “A”. '

This is from the despatch regarding Operation Substance (Malta Convoy July 1941):

The Sunderland A/S aircraft was instructed By V/S* at 1453 to locate Group 5 and to inform Rear-Admiral Commanding, i8th Cruiser Squadron that Group 4 would remain 20 miles to the eastward of the convoy during the night and close at daylight. This Sunderland returned at 1732 reporting Group 5 bearing 240°, 25 miles from RENOWN. RearAdmiral Commanding, i8th Cruiser Squadron reported via this aircraft that one French merchant ship had passed northbound 9 miles ahead of the convoy at 1300, that all destroyers had been fuelled during the day from BROWN RANGER and that Group 5 would pass through position 37° 40' N., 6° 25' E. at 0300/23.

RFA Cairndale:

26 March 1941 sailed Gibraltar escorted by corvettes HMS's FLEUR DE LYS and COREOPSIS for operation PEDESTAL [a planned but cancelled operation], the refueling British ships in 32°30N, 32°30W...

25 May 1941 fitted for OAS [refueling at sea]operations, she sailed from Gibraltar with the store ship City of Dieppe escorted by HMS/m SEVERN to act as the oiler for Force H, the Squadron hunting the German battle cruiser BISMARCK and patrolled in the vicinity of 43°00 N 35°00 W. After the BISMARCK was sunk, she was ordered to return to Gibraltar

30 May 1941 when in position 35°19N 08°33E, 100 miles NW of Casablanca in the Eastern Atlantic under escort of HM corvettes COREOPSIS and FLEUR DE LYS torpedoed with two torpedoes by the Italian submarine Guglielmo Marconi and sank in four minutes. Four members of the crew were killed and have no known grave but the sea. The three who died are remembered with pride on the Tower Hill Memorial and one on the Halifax Memorial, Canada. Her Master and other survivors were saved by the rescue tug HMS ST DAY and were landed at Gibraltar.
https://web.archive.org/web/20190215223 ... nformation

The source you cited above states:

While these two early techniques were in use before 1939 it was only after they had
been proven were they adopted by the RFA.

and as we can see above the RFA adopted OAS prior to May 1941.

By 1942 Ranger class RFAs were routinely
refuelling Atlantic and Arctic convoy escorts, three at a time, and they supported 21
of the 25 Arctic Convoys. Nineteen RFAs were lost during the war including Aldersdale
on the 1942 Arctic Convoy PQ17, and Grey Ranger on the return convoy QP14.19

This statement isn't wrong, but RFA Ranger class oilers were routinely OAS RN ships in 1941.

Although the Admiralty’s RFAs were undertaking RAS in the early years of the Second
World War,

This is correct but the author should have provided more specifics. Such as:
RFA Bishopdale:

June 1941 RASed with HMS EAGLE near the Azores being protected by HMS DUNEDIN (Force F)

6 June 1941 RASed with HMS DUNEDIN while being protected by HMS EAGLE

9 June 1941 RASed with HMS DUNEDIN again while being protected by HMS EAGLE

12 June 1941 further RAS with HMS EAGLE followed by HMS DUNEDIN. All ships being protected by HMS EAGLE's Swordfish aircraft
https://web.archive.org/web/20190215211 ... bishopdale

[Michael L]

Steve Crandell wrote:
He didn't consider Rodney and Nelson to be modern?

The Nelson class were the only interwar battleships built and launched by the British. As I suspect Forum Members know, their design was impacted by the Washington Treaty of 1922.

Wikipedia: The limits of the treaty inevitably led to compromises in the design of two new ships, and the resulting Nelson class sacrificed installed power (and hence speed) in order that they be well-armed and defended. They were often referred to as the "Cherry Tree" class, because they had been "cut down by Washington".

Rodney and Nelson were both commissioned in 1927. The Nelson class had a top speed of 23 knots.

The King George V class battleships were the most modern British battleships in commission during the Second World War. HMS King George V commissioned 1940. King George V class were designed after the Washington Treaty had expired and been replaced by the Second London Naval Treaty, 1936.

On 22 May 1941 HMS Rodney sailed from Clyde escorting the Britannic to America. HMS Rodney itself was bound for the Boston Navy yard for refit. After the Bismarck saga, HMS Rodney again departed for the Boston Navy yard arriving 12 June 1941. The refit took two months.
https://www.naval-history.net/xGM-Chron ... Rodney.htm
As for HMS Nelson, during its pre-war service the ship was given periodic refits and some refits were also conducted during the War. But a planned full modernisation was not carried out because of the outbreak of war. http://www.naval-history.net/xGM-Chrono-01BB-Nelson.htm

It was in this context that I made the statement; “Admiral Tovey was very conscious of the KGV being the only serviceable modern British RN Battleship and the need to preserve it by returning to a UK port.” Whether Admiral Tovey consider Rodney and Nelson to be modern, I do not know.

[Michael L]

Again I stand corrected by Mr dunmunro. The Royal Navy was conducting oiling at sea (OAS) pre-war and in the early years of the War. Thank you for the examples of destroyers being refueled by battleships in the Mediterranean – robbing Peter to pay Paul. And the use of RFA Brown Ranger during Operation Substance. I am still of the opinion that in the early years of the War, other countries RAS/OAS capabilities and expertise were more developed than that of the RN.

I did understand that Oiler destinations were patrol lines, not a single position. “… patrol on a line 60 miles 225° from 43° 35°”
With respect to the following:

RFA Cairndale.
25 May 1941 fitted for OAS operations, she sailed from Gibraltar with the store ship City of Dieppe escorted by HMS/m SEVERN to act as the oiler for Force H, the Squadron hunting the German battle cruiser BISMARCK and patrolled in the vicinity of 43°00 N 35°00 W. After the BISMARCK was sunk, she was ordered to return to Gibraltar. https://web.archive.org/web/20190215223 ... nformation

And the message sent by ‘V.C.N.S., 2030B/24 to C. in C. H.F., CO Force H., etc, etc.’; 24.5.1941.

1 (a) Oiler CAIRNDALE fitted for oiling at sea, and with scuttling charges has been sailed from Gibraltar to patrol on a line 60 miles 225° from 43° 35°.
1 (b) Severn will escort CAIRNDALE who is expected to reach the patrol line about 31/5.

Gibraltar is located at 36.1408° N, 5.3536° W. RFA Cairndale, Stores Ship City of Dieppe, escorted by the HM Submarine Severn “patrolled in the vicinity of 43°00 N 35°00 W.” I calculate the distance from Gibraltar to the patrol area to be approximately 1,440 NM. RFA Cairndale had a top speed of 11.5 knots. I calculate it would take five days to travel the distance at top speed. V.C.N.S. estimated six days.
After the BISMARCK was sunk, RFA Caurndale was ordered to return to Gibraltar. Therefore, RFA Cairndale sailed out for two and a half days, 25, 26 and half 27. Then sailed back - half 27, 28 and 29.
Then RFA Caindale was sunk on 30 May 1941, in position 35°19N 08°33E, 100 miles NW of Casablanca.

In doing what I call a gross error check, I find the following anomalies.
One reference states that the RFA sailed on 25 May. Another says it sailed late on 24 May. Maybe the orders were issued late on 24 and it sailed on 25?
One reference states that RFA Cairndale acted “as the oiler for Force H the Squadron hunting the German battle cruiser BISMARCK.” The position the Bismarck was sunk at was approx. 48° N 16° W. Force H was operating in this vicinity. If RFA Cairndale was 'the oiler for Force H', why was it being sent to a patrol area at 43°00 N 35°00 W (850 NM away)? IMHO, this does not make sense. Something is missing.
One reference states the RFA “patrolled [past tense] in the vicinity of 43°00 N 35°00 W”. Simple maths shows that it could never have made it to the patrol area and back to Gibraltar in the time/days available.
Bismarck was a 'battleship', not a 'battle cruiser'. A simple enough error.
One might consider such anomalies as 'nitpicking'.

With respect to your following opinion.

Tovey probably didn't mention the possibility of refueling in Eire, IMHO, because the despatch was a public document and disclosure of sensitive matters regarding Eire would have caused diplomatic issues for both the UK and Eire governments.

I disagree. The Despatch dated 5 July 1941 was submitted to the Lords Commissioners of the Admiralty, by Admiral Sir JOHN C. TOVEY, K.C.B., D.S.O., Commander-in-Chief, Home Fleet – at the time not a public document. IIRC the Despatch was only released as a public document when it was published in the London Gazette in October 1947. IMHO there were no concerns regarding diplomatic issues for both the UK and Eire governments.

If we are to accept the harsh realities associated with the study of history, we need to recognise that as well as double checking the accuracy of secondary sources, primary sources should also be the subject of scrutiny. In this respect, I cite how HMS Neptune was awarded the Battle Honour BISMARCK (1941), when the evidence clearly shows that the ship took no part in the search for the Bismarck 23-27 May.
https://www.kbismarck.org/forum/viewtop ... une#p90862

But, all this is taking us away from the subject of this Post, namely – ‘Hypothetical: The British detect Bismarck with a ship-borne Walrus at 0900 on 25 May 1941.’
Do you have anything to contribute to this hypothetical? Thank you by the way for the Map you uploaded. Very helpful.
Or are you content to simply provide me with evidence correcting statements I have made (which I have appreciated as it has broadened my knowledge) and take the discussion off on a tangent?
I am happy either way.

Sincerely, Michael L.

[dunmunro]

Again I stand corrected by Mr dunmunro. The Royal Navy was conducting oiling at sea (OAS) pre-war and in the early years of the War. Thank you for the examples of destroyers being refueled by battleships in the Mediterranean – robbing Peter to pay Paul. And the use of RFA Brown Ranger during Operation Substance. I am still of the opinion that in the early years of the War, other countries RAS/OAS capabilities and expertise were more developed than that of the RN.

I did understand that Oiler destinations were patrol lines, not a single position. “… patrol on a line 60 miles 225° from 43° 35°”
With respect to the following:

RFA Cairndale.
25 May 1941 fitted for OAS operations, she sailed from Gibraltar with the store ship City of Dieppe escorted by HMS/m SEVERN to act as the oiler for Force H, the Squadron hunting the German battle cruiser BISMARCK and patrolled in the vicinity of 43°00 N 35°00 W. After the BISMARCK was sunk, she was ordered to return to Gibraltar. https://web.archive.org/web/20190215223 ... nformation

And the message sent by ‘V.C.N.S., 2030B/24 to C. in C. H.F., CO Force H., etc, etc.’; 24.5.1941.

1 (a) Oiler CAIRNDALE fitted for oiling at sea, and with scuttling charges has been sailed from Gibraltar to patrol on a line 60 miles 225° from 43° 35°.
1 (b) Severn will escort CAIRNDALE who is expected to reach the patrol line about 31/5.

Gibraltar is located at 36.1408° N, 5.3536° W. RFA Cairndale, Stores Ship City of Dieppe, escorted by the HM Submarine Severn “patrolled in the vicinity of 43°00 N 35°00 W.” I calculate the distance from Gibraltar to the patrol area to be approximately 1,440 NM. RFA Cairndale had a top speed of 11.5 knots. I calculate it would take five days to travel the distance at top speed. V.C.N.S. estimated six days.
After the BISMARCK was sunk, RFA Caurndale was ordered to return to Gibraltar. Therefore, RFA Cairndale sailed out for two and a half days, 25, 26 and half 27. Then sailed back - half 27, 28 and 29.
Then RFA Caindale was sunk on 30 May 1941, in position 35°19N 08°33E, 100 miles NW of Casablanca.

In doing what I call a gross error check, I find the following anomalies.
One reference states that the RFA sailed on 25 May. Another says it sailed late on 24 May. Maybe the orders were issued late on 24 and it sailed on 25?
One reference states that RFA Cairndale acted “as the oiler for Force H the Squadron hunting the German battle cruiser BISMARCK.” The position the Bismarck was sunk at was approx. 48° N 16° W. Force H was operating in this vicinity. If RFA Cairndale was 'the oiler for Force H', why was it being sent to a patrol area at 43°00 N 35°00 W (850 NM away)? IMHO, this does not make sense. Something is missing.
One reference states the RFA “patrolled [past tense] in the vicinity of 43°00 N 35°00 W”. Simple maths shows that it could never have made it to the patrol area and back to Gibraltar in the time/days available.
Bismarck was a 'battleship', not a 'battle cruiser'. A simple enough error.
One might consider such anomalies as 'nitpicking'.

With respect to your following opinion.

Tovey probably didn't mention the possibility of refueling in Eire, IMHO, because the despatch was a public document and disclosure of sensitive matters regarding Eire would have caused diplomatic issues for both the UK and Eire governments.

I disagree. The Despatch dated 5 July 1941 was submitted to the Lords Commissioners of the Admiralty, by Admiral Sir JOHN C. TOVEY, K.C.B., D.S.O., Commander-in-Chief, Home Fleet – at the time not a public document. IIRC the Despatch was only released as a public document when it was published in the London Gazette in October 1947. IMHO there were no concerns regarding diplomatic issues for both the UK and Eire governments.

If we are to accept the harsh realities associated with the study of history, we need to recognise that as well as double checking the accuracy of secondary sources, primary sources should also be the subject of scrutiny. In this respect, I cite how HMS Neptune was awarded the Battle Honour BISMARCK (1941), when the evidence clearly shows that the ship took no part in the search for the Bismarck 23-27 May.
https://www.kbismarck.org/forum/viewtop ... une#p90862

But, all this is taking us away from the subject of this Post, namely – ‘Hypothetical: The British detect Bismarck with a ship-borne Walrus at 0900 on 25 May 1941.’
Do you have anything to contribute to this hypothetical? Thank you by the way for the Map you uploaded. Very helpful.
Or are you content to simply provide me with evidence correcting statements I have made (which I have appreciated as it has broadened my knowledge) and take the discussion off on a tangent?
I am happy either way.

Sincerely, Michael L.

Oilers are tankers that are fitted for refueling at sea. The RN preferred to use oilers in sheltered waters where the weather was less of a factor, but they could, and did, refuel at sea.

The battleships off Crete had lots of fuel and the provision for RAS from cruisers/battleships to destroyers was made with this in mind. The KM did the same as did the USN and IJN.

The USN's first attempts to use oilers operationally in early 1942 to relieve Wake Island ended in near complete failure. Had they used then current RN oilers and techniques the operation would, most likely, have succeeded, at least from the perspective of fuel:

Although the round-trip voyage from Pearl Harbor to Wake Island was well within the cruising range of the destroyers, they would have had virtually no reserves for battle. They would need to take on oil en route to insure sufficient fuel for engaging the enemy.6 Ordered to "fuel at [his] discretion," Fletcher decided to wait until he was just outside the air-search range of the enemy forces attacking Wake before refueling. By the evening of 21 December, the task force was closing to within 600 miles of Wake, close enough to the battle zone to begin topping off the accompanying destroyers on the next day. Unfortunately for Fletcher's reputation, the ensuing operation was hampered by moderate winds and a long cross-swell that made fueling extremely difficult. "Several towlines parted, seven oil hoses were ruptured, and only four destroyers were filled during a ten-hour fueling period." The force was still 425 miles from Wake on the morning of 23 December, yet four of the destroyers still had to be fueled. By then it was too late to save the island and Fletcher's force was recalled.7
There is no question the task force's speed of advance was greatly hindered by the slow steaming speed of the Neches (she could make no more than 12 3/4 knots) and the two days it took to refuel the destroyers' accompanying escorts (see table 17). Because of these delays
Fletcher was unjustly blamed by some naval officers for the failure to relieve Wake...
http://www.ibiblio.org/hyperwar/USN/GSBO/GSBO-17.html

The state of proficiency of RAS in the RN and USN in 1941/42 is a matter for close study.

Despatches are written for public consumption, and in 1947 disclosure that the RN had made plans to refuel Tovey's ships in Eire ports would have created problems in London and Dublin. As it turned out Tovey didn't need to refuel in Eire or even Northern Irish ports and went onward to Scotland.

The Admiralty feared that Bismarck and PE would rendezvous with KM Oilers in the southern areas of the North Atlantic.

The key takeaway from the AWD entries:

24.5.1941

Oilers Disposition

1 (a) Oiler CAIRNDALE fitted for oiling
at sea, and with scuttling charges has
been sailed from Gibraltar to patrol on
a line 60 miles 225° from 43° 35°.

1 (b) Severn will escort CAIRNDALE who is
expected to reach the patrol line about
31/5.

2. Oiler is being sent to St. Johns, N.F.
Capital ships can be fuelled in emergency
from oiler in Concepcion Bay.

3. There are tankers in convoys HX 187
and 128 with fuel oil.

4. Enquiries are being made whether any
U.S. oiler facilities can be made
available.

5. Oiler SAN ADOLFO has been ordered to
patrol a line 60 miles 225° from position
39° 49°. She should reach this position
about 28/5.

6. Attention is drawn to Chart of Sea
Surface Conditions for May Y 185 recently
issued.

(V.C.N.S., 2030B/24 to C. in C. H.F., CO Force H., etc, etc.)

is the very last line: " V.C.N.S., 2030B/24 to C. in C. H.F., CO Force H., etc, etc."

The fact that there are transcription errors is unimportant (but thanks for finding them) compared to the statements that the Admiralty (informing Tovey) was taking all the needed steps to ensure that RN ships at sea had access to fuel.


The admiralty informed Tovey of the disposition of RFA oilers and where he could expect to find them. Tovey, of course had the option to make use of these oilers as he saw fit and could request that the Admiralty order the oilers to any needed rendezvous point. This is all factual information and it shows that Tovey had lots of options open to him in terms of fuel. It also shows that the Admiralty was taking calculated risks when it ordered RN ships to maintain the hunt for Bismarck despite their fuel state as they (the Admiralty) had the option to refuel ships at sea. This is an aspect of the Bismarck operation that just doesn't appear in secondary source accounts, including Tovey's despatch.

I'm not sure what else I can add regarding the potential use of Walrus recon aircraft, except to state that the problems of locating the mothership after a ~6 hour flight, whilst the mothership will have travelled ~150nm, is quite daunting.

[Michael L]

Hello Mr dunmunro.
True enough. 'The Admiralty was taking calculated risks when it ordered RN ships to maintain the hunt for Bismarck despite their fuel state, as the Admiralty had provide options to refuel ships at sea.' But I think you have forgotten the last piece of information/advice the Admiralty gave to Admiral Tovey on the matter of fuel. If I recall correctly:

BISMARCK must be sunk at all costs and if to do this it is necessary for KING GEORGE V to remain on the scene then she must do so even if it subsequently means towing KING GEORGE V . [Emphasis added by me.]
1st Sea Lord to C in C HF 11.37B Most Immediate Naval Cypher F.

Pound did apologise for the signal stating it should never have been sent, I think he mentions it should be expunged from the records (any expungement would have been difficult as every ship and station would have received it). Tovey states he believed it came from Pound but also states that if he had known that it in fact had come from Churchill he would have included reference to it in his despatch.
Forum; The KGV and Adm fuel signals on May 26 and 27. https://www.kbismarck.org/forum/viewtopic.php?t=8246

Thank you for your contribution to the hypothetical post:
“I'm not sure what else I can add regarding the potential use of Walrus recon aircraft, except to state that the problems of locating the mothership after a ~6 hour flight, whilst the mothership will have travelled ~150nm, is quite daunting.”
I agree, it would have been daunting. I presume that is why one of the Walrus' crew was an Observer/Navigator. IIRC most aircraft were also equipped with a radio and a Radio Operator.

Kind regards, Michael L.

[dunmunro]

Hello Mr dunmunro.
True enough. 'The Admiralty was taking calculated risks when it ordered RN ships to maintain the hunt for Bismarck despite their fuel state, as the Admiralty had provide options to refuel ships at sea.' But I think you have forgotten the last piece of information/advice the Admiralty gave to Admiral Tovey on the matter of fuel. If I recall correctly:

BISMARCK must be sunk at all costs and if to do this it is necessary for KING GEORGE V to remain on the scene then she must do so even if it subsequently means towing KING GEORGE V . [Emphasis added by me.]
1st Sea Lord to C in C HF 11.37B Most Immediate Naval Cypher F.

Pound did apologise for the signal stating it should never have been sent, I think he mentions it should be expunged from the records (any expungement would have been difficult as every ship and station would have received it). Tovey states he believed it came from Pound but also states that if he had known that it in fact had come from Churchill he would have included reference to it in his despatch.
Forum; The KGV and Adm fuel signals on May 26 and 27. https://www.kbismarck.org/forum/viewtopic.php?t=8246

Thank you for your contribution to the hypothetical post:
“I'm not sure what else I can add regarding the potential use of Walrus recon aircraft, except to state that the problems of locating the mothership after a ~6 hour flight, whilst the mothership will have travelled ~150nm, is quite daunting.”
I agree, it would have been daunting. I presume that is why one of the Walrus' crew was an Observer/Navigator. IIRC most aircraft were also equipped with a radio and a Radio Operator.

Kind regards, Michael L.

However, now that you know that the RN had oilers capable of RASing KGV, you can understand that towing KGV would not have been necessary. The signal which appears to have originated from Churchill, basically was authorizing Tovey to take extraordinary risks to ensure Bismarck's destruction, but even if KGV had to remain on scene for another ~12 hours she could have still made it to an Irish port, and another ~12 to 24 hours would have meant rendezvous with an oiler with KGV joining Force H.

It would have been almost certain suicide for the crew of a Walrus attempting a long range recon mission on 25 May. It would have also been problematic for KGV, in that she would have be at an agreed upon in advance fixed position for the Walrus to have any hope of recovery, and KGV would have had to break radio silence, if Bismarck was actually spotted, to give the Walrus an updated position, as KGV would have had to make a rather abrupt change of course to intercept Bismarck.