WATU Wargame Report 2023

On Saturday 6^th May, the Western Approaches Tactical School was once again operational in Derby House for a celebration of the wargaming Wrens of WATU and the 80^th Anniversary of the Battle of the Atlantic. Analysts and wargamers from WATU’s direct-descendant organisations—Dstl, the Maritime Warfare Centre, and HMS Eaglet—took up the roles of WATU Wrens, RN Convoy Escort, and dastardly U-Boats, joined by folks from Defence Academy Shrivenham, US Navy, McGill and York University.

Our WATU Wrens and players were a mix of new wargamers and old hands, men and women, professional and hobby wargamers, serving and retired naval officers, and academics.

The challenge on the Tactical Table was the night of 6^th/7^th May, 1943. A moderate sea, bright moonlight, and intelligence reports of five U-Boats operating in the vicinity of (the entirely fictional) Convoy ONS 506, a slow convoy comprising 12 ships sailing for Halifax. Escort Group B7, consisting of HM Ships D1 (destroyer and Senior Officer Escort), L1 (Black Swan class sloop), and Flower class corvettes P1, P2, P3, and P4, were in Night Escort Six disposition. A substantial wolfpack attack developed at midnight, beginning the game with the torpedoing of the merchant ship in column 3 row 2.

Here’s what the first view-giving looked like, and the same plot from the Wren’s perspective:

The gap in the convoy is our sinking merchant ship. Where could the U-Boat be that fired the torpedo? How many other U-Boats are making an attack? Their tracks are plotted in red pen to hide them from the players. The U-Boat positions are highlighted on the right for clarity, the star is a mischievous shoal of fish.

The first view-giving included the burning wreck of our merchant ship and a surfaced U-Boat sighted at the rear of the convoy. L1 closed for an exchange of gunfire, here is their (and other’s) orders:

Our players had a copy of the relevant parts of the Atlantic Convoy Instructions, including Op: RASPBERRY, which was quickly ordered and developed two asdic contacts at the front of the convoy.

Our Wrens made use of the adjudication tables to decide which of the in-range radar (all of them at this range), asdic and visual contacts to report. Here’s a few turn’s worth of contacts for L1, and a large stack-o-signals:

Oh goodness, there were signals. There were so many signals. WATU had a team of three Wrens and an RN Yeoman handling signals: players handed in signals to be sent, the Wrens copied them to all recipients, and delivered them after some transmission delay. In our game, Lynn O’Donnell handled everything, and our players sent so many signals that we ran out of paper. Here’s a few of them:

While all this was going on, visitors to the museum were grilling Paul and Lt Phil Roberts RNR (Rtd) about the game and the history:

Meanwhile, some familiar faces, and actual submarine warfare officers, were busy plotting the demise of our convoy, upstairs in Admiral Sir Max Horton’s office. While submerged, they didn’t get a look at plot, when surfaced they could peek out the window down onto the plot in the Map Room. Their orders and contacts were sent over the museum’s wifi:

How did our Escort Group do?

It was carnage in the convoy! Six merchant ships lost. But the Escort managed two creditable depth charge attack runs, one of which forced the target to the surface in what was likely to be its death-throes. They also avoided depth charging the shoal of fish (which was mostly down to failing to get an asdic contact rather than good judgement…)

Here is the 1943/2023 edition of the After Action News, hot off the press:

WATU NewsDownload

See also Report of Proceedings from MacKay, RNWR, in command of sloop L1, here.

How realistic was the game?

Well, there are a few reasons why the U-Boats had the upper-hand:

Firstly, in the interests of a fun time for all, our U-Boats all started within 2,000 yards of the convoy. In reality, U-Boats tended not to attack simultaneously like this. Particularly not when using pattern-running torpedoes (as we were), because of the risk of friendly-fire incidents.

Second, we only played 12 minutes of game-time, and an engagement is typically 30 minutes plus. Knowing we were unlikely to play out 20 minutes, we started in-media-res with the U-Boats well inside radar contact range and the extended screen. It’s likely at least some of our U-Boats would have been caught further from the convoy, allowing time for interception before they were able to get off any torpedo shots, which would have improved the score sheet for the convoy somewhat.

Third: the score sheet seems to favour the U-Boats, but one U-Boat was probably not going to survive the next 2 minutes, and the other two were not going to cause too much more trouble for a time. If the game had gone on longer I think we would have seen the tide turning in favour of the Escort.

Finally, the losses seem pretty high, but our convoy was extremely small (for convenience, and for interest—a bigger convoy would mean spending most of the game steaming to get near-enough to contacts to do the fun stuff). The whole point of the convoy system was that the losses were similar regardless of the size of convoy; a bigger convoy would have lost proportionately fewer ships.

In terms of the gameplay: it was certainly a lesson in communication between the Escort players, to co-ordinate a response to contacts without the screen descending into magnet-ball. The outcome of actual attacks were pretty realistic: with a lethal range of only 7 yards, depth charge attacks were about 10% effective. U-Boat kills generally came from hunting to exhaustion, which Escort Groups could not afford to do—this is why Support Groups were introduced in March 1943. We didn’t have enough players and Wrens to support more than six in our Escort, so even if we’d played longer, the chances of killing the submerged U-Boats were small.

The ploting & adjudication rules revision/expansion/better-recreation since the 2018 game made for a much more interesting game: the U-Boat players were thinking about more than just shoot-dive-hide, and there was a passable attempt at RASPBERRY from an Escort group who (with the exception of the Senior Officer Escort) had zero experience of ASW tactics.

I want to thank the Western Approaches Museum for hosting our game and giving us free-run of the Map Room, and about thirty Dstl & MWC folks who took part in the playtest/training games as well as the Big Event. It was pretty special to play a Derby House Principles wargame in the actual Derby House. I had an absolute blast. So did Tom’s U-Boat (har dee har) !

WATU Wargame Returning to Liverpool

It’s the 80^th Anniversary of the Battle of the Atlantic, and back in 1943, the 6^th May marked the turning-point where we stopped losing and started making life so difficult for U-Boats that for a time they withdrew from the Atlantic entirely, and when they returned (in September 1943) they never again had the upper-hand.

So what better time to recreate the Western Approaches Tactical Unit wargame at WAHQ again?

Formed in 1942 to solve the U-Boat problem in the Atlantic, WATU was staffed almost entirely by women, and men unfit for duty at sea through illness and injury. The Wrens came from all walks of life and all across (what was then) the Empire, and were responsible for teaching the Allied navies convoy escort tactics: how to find and sink U-Boats. 

Since the last time we played in 2018, I’ve found WATU Wrens alive and kicking, and learnt a lot more about how the game works, so this time we’re playing with:

Actual pieces from the WATU game:

When WATU demobbed, Cpt Roberts gifted the ships to the Wrens as souvenirs: Leading Wren Helen Coop’s ship has been scanned using photogrammetry, turned into CAD, and lovingly recreated by Ian Greig.

In grey is a test-print with a filament printer, in translucent is a print from a UV-setting resin printer, and one laser-cut from wood, ready for painting:

Actual game chits:

Leading Wren Helen Coop left us a treasure-trove in her scrapbook, including chits from actual WATU wargames played by Cpt Johnny Walker’s support group:

Nothing changes in wargaming: after rolling a 1, Cdr Wemyss would like a new gun crew please :-P

Plotting tools:

In the 2018 game we used a crude movement template to help with plotting, and mostly ignored turning circles. This was partly a simplification to help the players (WATU had the distinct advantage that their players came knowing how to command their ship and plot it on a chart! Our players were liable to try impossible things), and partly due to a lack of data. Since then I’ve found a lot more photos with details of the plot, and hunted down data on period ships which was not easy to find. 

The result is this Rather Excellent [TM] recreation of the plotting protractor, laser-cut by Ian Greig. They work magnificently well and look amazing. Figuring out what they were from a handful of WATU photos might be my favourite bit of wargaming geekery :-)

Side-by-side comparison of the Canadian Tactical Table protractor and our recreation.

Actual adjudication tables (probably):

Chris Carlson dug up some post-war ASW tables which are probably a later version of the WATU adjudication tables. One of the big mysteries of the WATU game has been how all that stuff happened, since the pre-war (1921 & 1929) RN War Game rules are not the WATU game (it’s a fundamentally different game that’s been mistaken for the WATU game by some because it mentions “screens”, but it’s very clearly talking about putting down screens on the plot to screen the surface ships from each other when they’re out of visible contact, not viewing the entire plot from behind a screen to obfuscate the U-Boat tracks on the plot), and the contemporary descriptions forget to mention how you adjudicate an attack. Even these tables don’t really explain how they’re used, but they fit broadly with the assumptions we made for the 2018 game, which is pleasing! 

Well…all except one thing: we used D100s, and it turns out that because dice were too new-fangled (or D100s were hard to come by in 1942, or the Temperance Movement had words), WATU used a 1 to 100 tombola.

I appear to have bought one large enough for Raspberry to go to sea in… stop by WAHQ during the game and you can draw the fate of a U-Boat, Escort, or merchant ship from the adjudication tombola :-)

U-Boat artefacts:

Big Heritage, who run the WAHQ museum, acquired a U-Boat during lockdown, and are busy renovating it and creating a Battle of the Atlantic Museum across the Mersey from WAHQ.

The original plan for this game was for the U-Boat players to play from the actual U-Boat, but the new museum is still a building site, so instead we’re bringing some of the U-Boat artefacts over to WAHQ for the day. Our U-Boat players have been practicing with attack discs to get their firing solution. We’ll see if they’re able to sink anything!

We’re also hoping to make use of the Y-Service teleprinter which has been refurbished to run off a Raspberry Pi, for sending our convoy relevant Engima decrypts.

Come to WAHQ on Saturday 6^th May and you’ll get to:

• Celebrate the remarkable achievements of the WATU Wrens!
• Chat with the direct descendants of WATU about careers in professional wargaming: yes, you can get paid to play board/war/computer games for a living ;-)
• See the WATU game in action, send some signals to the convoy if you’d like.
• Explore the Western Approaches Museum, including their new Wrens exhibition, Leading Wren Helen Coop’s WATU scrapbook, and bits from their newly-acquired U-Boat.
• Say hello to a handful of PAXsims editors :-P
• Delight in a Derby House Principles wargame being played in the actual Derby House that the principles are named for. 

Canadians can also check out the WATU gallery at the Canadian War Museum‘s up-coming wargaming exhibition.

Read more about the Derby House Principles for diversity and inclusion in professional wargaming here.

Lindybeige on WATU

Nikolas Lloyd—better known as popular military historian Lindybeige on YouTube—has produce a video on the important wargaming of the Western Approaches Tactical Unit during WWII.

Here on PAXsims you can read Paul Strong’s paper on WATU, as well as about the WATU wargame recreation that we will be conducting (with Dstl and the Royal Navy Maritime Warfare Centre) at the Western Approaches museum in Liverpool on September 8.

h/t Peter Perla

WATU wargame at Western Approaches war museum, September 8

On Saturday,  8 September 2018, volunteers from the Defence Science and Technology Laboratory, the Royal Navy Maritime Warfare Centre, and PAXsims will be at the Western Approaches museum in Liverpool to recreate a WWII convoy escort wargame, of the sort conducted by the Western Approaches Tactical Unit.

Almost besides ourselves with excitement about an exciting event being staged at WA on September 8th – keep you diary free pic.twitter.com/3VbJ0TR0Vh

— Western Approaches (@WestApproaches) July 18, 2018

This will be a unique opportunity to see the gaming techniques that helped turn the tide of the Battle of the Atlantic—and to honour the work of Captain Gilbert Roberts and the women and men of WATU. Hope to see you there!

 

WWII convoy escort game: The RAN version

HMAS Nepal

From the Royal Australian Navy archives comes this September 1943 summary of a “convoy escort” game,” apparently based on the work of the Western Approaches Tactical Unit in the UK:

The convoy escort game described below has been designed to exercise Commanding Officers of Escort Vessels and their teams in dealing with attacks on convoys. It has been played successfully in England and is recommended as an interesting and valuable means in improving efficiency and team work of convoy escorts.

The game can be played either in a ship or ashore, being organised on a day when several ships are in harbour.

You’ll find a transcription of the brief instructions here (courtesy of Sally Davis, who has also kindly removed the former WWII classification markings so that they won’t cause problems with government firewalls).

What is not not made clear is how adjudication is undertaken—that is, how target spotting or the effects of torpedo attacks or depth charges were determined.So far there is no evidence of dice or other stochastic methods being used in the WATU game, so it all may have been free kriegsspiel dependant on the judgment of expert umpires.

If you come across any information on WATU wargaming, do pass it on!

h/t Sally Davis

Wargaming the Atlantic War: Captain Gilbert Roberts and the Wrens of the Western Approaches Tactical Unit

Western Approaches war museum, Liverpool.

PAXsims is pleased to provide an early Christmas/holiday present to our readers: namely,  the longer version of Paul Strong’s article on one of the most important examples of operational wargaming during World War II: Wargaming the Atlantic War: Captain Gilbert Roberts and the Wrens of the Western Approaches Tactical Unit (pdf).

The piece is important both for shedding light on the role of WATU during the critical Battle of the Atlantic, but also in highlighting the key—and heretofore largely unrecognized—role that women wargamers played in the Allied war effort.

I took a special visit to the recently-revamped Western Approaches war museum in Liverpool during my last UK visit. I’m pleased to report that they are planning a major display and activity focused on the role of WATU.

100% being planned on a massive scale. https://t.co/C5RZ9iSaXo

— Western Approaches (@WestApproaches) December 1, 2017

Western Approaches war museum, Liverpool.

 

 

The wargaming Wrens of the Western Approaches Tactical Unit

In the latest issue of the Women in War newsletter (Autumn/Winter 2016), Paul Strong outlines the crucial role that members of the Women’s Royal Naval Service (WRNS, better known as Wrens) played as anti-submarine warfare operations analysts and wargamers in the Western Approaches Tactical Unit during Battle of the Atlantic. I’ve excerpted some sections below, but you really should read the whole thing.

Sir Charles summoned Captain Gilbert Roberts, an experienced officer who has been invalidated out of the service due to tuberculosis, to the Admiralty to discuss options for resolving Churchill’s concerns with Admiral Sir Cecil Usborne, the First Sea Lord’s adviser on Anti Submarine Warfare (ASW).

Usborne believed that there was a chronic lack of escorts but that the tactics they used were probably sub-optimal. Roberts was to form a new operational analysis team, to be called the Western Approaches Tactical Unit (WATU) to explore and evaluate new tactics and then to pass them on to escort captains in a dedicated ASW course.

…

The WATU facility was primitive, with tactical tables, a tactical floor divided into squares, basic ship models and a lecture theatre, but Roberts quickly got to work. A basic set of wargame rules was developed with processes to represent real-time decision cycles, tactical doctrine, and communications issues. Then the room was re-designed so that players representing escort commanders could only see the gameplay through a restrictive screen to represent the limited information that they would have in a real battle. The U-Boat track was invisible to players and shown as a brown chalk line so the umpires could follow its progress.

Roberts was assigned a small staff, Chief Petty Officer Raynor was the first then the Wrens appeared. Four Wren officers, Elizabeth Drake, Jane Howes, Jean Laidlaw and Nan Wailes, described as ‘real gems’ by Roberts, all brimming with enthusiasm and delighted to be doing serious work. In addition, four Wren ratings appeared, two were only seventeen.

…

A sceptical Sir Percy Noble arrived with his staff the next day and watched as the team worked through a series of attacks on convoy HG.76. As Roberts described the logic behind their assumptions about the tactics being used by the U-Boats and demonstrated the counter move, one that Wren Officer Laidlaw had mischievously named Raspberry, Sir Percy changed his view of the unit. From now on the WATU would be regular visitors to the Operations Room and all escort officers were expected to attend the course.

Interestingly, out of the 5,000 officers who attended the school, none had the slightest problem with being instructed by young Wrens – particularly as they proved extremely skilled at guiding their students through the more complex manoeuvres without hurting their feelings (there is an amusing but highly technical example in Mark William’s excellent biography Captain Gilbert Roberts RN and the Anti-U-Boat School).

Each of the courses looked at ASW and surface attacks on a convoy and the students were encouraged to take part in the wargames that evaluated potential new tactics. Raspbery was soon followed by Strawberry, Goosebery and Pineapple and as the RN went over to the offensive, the tactical priority shifted to hunting and killing U Boats. Roberts continued as Director of WATU but was also appointed as Assistant Chief of Staff Intelligence at Western Approaches Command.

…

When Roberts accepted his award as Commander of the British Empire at the end of 1943, he took a Wren Officer and Rating with him to Buckingham Palace, intentionally sharing the honour with the team of remarkable young women that helped the Western Approaches Tactical Unit win the Battle of the Atlantic.

 h/t Colin Marston

 

UPDATE: A longer version of Paul Strong’s research is can now be found here.