Identity of aircraft that mined the approaches to Holyhead port in July-August 1940?

[Sid Guttridge]

A merchant ship and two navalized fishing vessels were sunk by mines at the approaches to Holyhead port on 22 July and 16 August, 1940.
No U-boats laid mines in the Irish Sea, so it must have been an aircraft. It seems most likely that it was a Ju88.
Does anyone know what Luftwaffe unit laid these mines, what type the mines and aircraft were, and when?

Many thanks

Sid.

[Chris Goss]

It all depends on when these mines were dropped

[Nick Beale]

AFAIK most or all of the mining during the Battle of Britain was being carried out by units of the 9. Flieger Division but the Luftwaffe's daily sitreps don't go into detail, usually just referring to aircraft of the Division carrying out "special operations".

Here's one ULTRA from 5 August 1940:

At 0745 Seefliegerhorst 12/1 informed 9 Flieger Division that 50 air mines (Luftminen) type B and 40 air mines (LM) type A had arrived with escort detachment of Stabsfeldwebel Stefan. They were to be stored 1600/6/8. (A)

The “air mine advanced HQ” had not yet arrived. (C)

At 0800/5/8 Ltn. Lindner reported to Fl.Div. 9 that LM Vorkommando (air mines advanced HQ), strength 2 officers and 10 men had arrived at Brest Harbour station. (A)

NOTE: (A) and (C) are reliability ratings for Bletchely Park's interptretation of parts of the original message. (A) was the highest.

Also, from a Bletchley Park special report on the Luftwaffe order of battle, dated 5 August 1940: the 9. Fl.Div. included KG 4, KG 40, KGr. 126 and Kü.Fl.Gr. 106.

[Andy Mitchell]

Sid,

You may find additional information in T-1022 R1756 - Berichte zur Luftaktivität. This is a DKM report.

An example would be:

Night of 5-6.8.40

9. Division

Cardiff, Pembroke, Fishguard, Blyth, Aberdeen, Dundee and Firth of Forth each with 2 LM.

Middlesbrough and the Humber Estuary each with 3 LM

Hartlepool, Swansea and New Castle each with 4 LM.

The report concludes by listing the units that took part -

10 He 115 from K.Fl.Gr.106; 8 He 111 from I./KG4; 4 Ju 88 from III./KG 4 and 3 He 111 from K.Gr. 126.

[Chris Goss]

KG 4 operated further east so maybe KGr 126 but again the mines could have been dropped days before. I./KG 40 also dropped mines but this task was taken away from them after they lost two Condors in July 1940 and started using the plane correctly!

[Nick Beale]

I./KG 40 also dropped mines but this task was taken away from them after they lost two Condors in July 1940 and started using the plane correctly!

Also worth noting that on 27 July 1940 (according to Bundesarchiv RL 2-III/708a) I./KG 40 had just 9 (3) Fw 200s so I'd be inclined to think that one or other of the He 111 units was responsible for the mining.