To maintain secrecy, most of Markham's workers had been given the day off (📸 Google). Just six men battled for two hours using jacks and timber packings to get the wagon back onto the rails, with trains on the mainline, held to maintain secrecy, backing up all the time. /🧵

X-23's earlier move by rail from Chesterfield to Faslane had started badly. Loaded onto a rail wagon on tracks that ran inside Markham's yard (🗺️ National Library of Scotland), a bogie jumped the track as the train moved off towards the mainline.

Built by Markham's in Chesterfield, X-23 is named (📜 own collection) by Joyce Hallitt, wife of general manager Bill Hallitt of rival firm Broadbent in Huddersfield. The firms have been enjoying friendly rivalry over who can build X-craft quickest.

COPP 10's George Talbot later wrote: "Our battledress uniforms were very similar in appearance to those worn by the Greek government forces.

"A loss of one of our members in the civil war of a country we had been sent to help was a turn of fortune which we found hard to accept."

Broadbent's is told to remove modifications already incorporated into X-21 for COPP ops. It's the latest change in ever-shifting Admiralty requirements that led one construction worker to pen "The Little Ship Builders' Litany" to the Lords of the Admiralty (📜 own collection). /🧵

With only two teams using X-craft, COPP no longer needs both the two subs currently under construction that are earmarked for them. X-23, being built at Markham's in Chesterfield, will still join COPP but X-21, being built at Broadbent's in Huddersfield (📸 own), won't be needed.

Five teams are needed as it's planned recce will happen right up to D-Day (scheduled for early May). Tide and moon conditions only allow a 1-week window per month for ops. That dovetails nicely with ~2 weeks after each recce to write reports and 1 week to prep for the next op. (📸 Adobe Stock)

Forced ashore, they 'lie low' until after the landings have taken place on 22 January (📸 IWM NA 11387) and then make their way south, aiming to get through the frontline.

They're just yards from success when captured by German troops in early February 1944. 2/2

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Between Campbell's visits, Willmott and his men are frantically gathering more suitable equipment to Hayling Island.

Willmott envisages 3 months of training – but within weeks the first two teams are being rushed to the Med for recce of Sicily (🗺️ via McMaster University). /🧵

But his latest version is no use for covert ops: it lets out a loud 'bang' when firing a rod into the beach surface to see how far it penetrates (though it's later used by scientists investigating UK beaches comparable with the Normandy landing beaches). (📸 D-Day Story/NMRN)

Over coming months his enthusiasm becomes somewhat tiresome for COPP as they fend off ideas that have limited practical use. His 'beach tester' is developed from devices that he'd used to check the firmness of American salt flats (📸 Adobe Stock) before his land speed record.

At today's meeting is land and water speed-record holder Sir Malcolm Campbell (📸National Portrait Gallery, London). He's attached to COHQ developing 'Bond style' gear, including treated seaweed attached to concrete 'sinkers' that might be used to mark beaches on infrared photos.

But until James Cook is ready for them, they'll be based temporarily in southern England.

In the end the move north never happens (James Cook is pushed for space) and they remain based on Hayling Island near Portsmouth.

The plan is that COPP will be based at HMS James Cook, the newly opened Combined Operations navigation school in Scotland (📸 IWM A 29904). There they will be able to take their pick of the best naval officers who are going through James Cook's training courses.

Nigel Willmott is put in charge. He's already done beach reconnaissance in Rhodes (April 1941) and led a 'prototype' COPP unit dubbed Party Koodoo–Inhuman during the recent Operation Torch landings. (📸 via Special Forces Roll of Honour website)

After their arrival, ongoing tensions between the British and local communists result in them being briefly detained by Partisan forces. (🗺️ via McMaster University) 2/2

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