Wargaming the

01 August 2018 UK OFFICIAL © Crown copyright 2017 Dstl Paul Edward Strong Supplying War • Britain’s war effort required the constant flow of Allied cargo ships to be maintained

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL ASWThe LessonsTechnology of WWII

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL The Fall of France

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL The First ‘Happy Time’ Convoy Formation • Admiral Karl Dönitz needed more U-Boats to starve the UK into submission but the Mid Atlantic Gap enabled him to concentrate his limited forces

HMS Vimiera

RAF Short Sunderland

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL Western Approaches Command - Liverpool

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL Extending Protection: The Mid-Ocean Escort Force

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL The Second ‘Happy Time’

• ?

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL New Allies, New Challenges Admiral Sir Percy Noble

Admiral Ernest J King

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL “Find out what is happening in the Atlantic, find ways of getting the convoys through, and sink the U-boats!” Churchill - January 1942

Commander Gilbert Roberts

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL The Western Approaches Tactical Unit

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL ‘The Game’ – Understanding the Enemy

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL ‘The Game’ – Orders

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL ‘The Game’ – Processing the Turn

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL ‘The Game’ – Briefing the Turn

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL Nicholas Eugeniusz Plawski Monsarrat

‘Johnnie’ Walker Peter Gretton

Prince Philip Pierre de Morsier

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL The Game – ‘Analysis’ • Wren Officer Jean Laidlaw

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL The First Test • How were U-Boats making their attacks?

Stricken Type IX

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL ‘Chasing Shadows’ - The Beta Search Janet Okell

Sir Max Horton

HMS Vidette

01 August 2018

© Crown copyright 2017 UK OFFICIAL Dstl New Technologies & Tactics

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL Getting to the Church in Time Walker on HMS Starling (2nd Support Group) Escort and Support Groups in Action

HMS Duncan (Convoy HX-231)

HMS TAY (Convoy ON-5)

01 August 2018

© Crown copyright 2017 Dstl UK OFFICIAL Dönitz Plots Revenge

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL The T5 Acoustic Torpedo

Wolfpack Leuthen gathers in the Mid Atlantic Gap

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL They are going for the escorts!

Flower Class

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL Tooley Hawkings Reports…

HMS Orchis

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL Analysis in Action

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL Step Aside

A U-Boat shadowing the convoy looking Late 1942 range for a target was approximately 4,000 Yards

Convoy Course

Corvette spots a U-Boat and fires a star shell

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL Step Aside

Position C is the A optimum safe distance C U-Boat fires a T-5 from its stern tube B and dives

B Approx 1 mile C

60º The escort’s move to C means A that she evades the torpedo’s acoustic detection array

The Corvette turns as the U-Boat dives

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL Step Aside

At C the Corvette returns to C The submerged U-Boat a course that places her heads for a new position close to the U-Boat’s that enables her to continue predicted position to monitor the convoy and prepare a new attack

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL 01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL The End of ‘The Game’

01 August 2018

© Crown copyright 2016 Dstl UK OFFICIAL