10 August 1942 Part 6

10 August 1942 Island defence priorities tunnels proposed garrison and protected utilities

Date note: The date is that of Seventh Army’s report. Earlier orders and proposals are quoted within it. The proposed total of 36,960 is a planning requirement, not an actual garrison strength return.

Annex A1

Secret command matter

Seventh Army Headquarters

Ia / Army Engineer Commander

No. 465/42 [first figure faint; confirmed by the cross-reference on scan 0027], secret command matter

Army headquarters, 10 August 1942

Seven copies. Copy number [not entered or unreadable].

Reference: Commander in Chief West (Army Group D), Ia / General of Engineers, Pi.1 No. 187/42, secret command matter, dated 24 March 1942.

Subject: Permanent fortification of the Channel Islands. Tactical and technical design.

Enclosures: 2.

To Commander in Chief West (Army Group Headquarters D)

Following receipt of the reports from LXXXIV Army Corps headquarters and Fortress Engineer Commander XIV, the following is reported:

For each individual question, the orders of Army Group, the reports of LXXXIV Army Corps headquarters and Fortress Engineer Commander XIV, and the comments of Seventh Army Headquarters have been brought together.

I. General

Regarding Part I 1(a) of the referenced order

Commander in Chief West orders: “Experience in East Asia shows that landings frequently take place precisely at locations that are difficult to approach tactically and technically, because the attacker expects the weakest defences there and believes that surprising the defender there offers the greatest prospect of success.

The order of priority for construction must take particular account of this, especially in view of the planned construction periods of 14 months and 7 years.”

LXXXIV Army Corps headquarters reports: “In accordance with the orders issued in OKH / Army General Staff / Operations Branch / General of Artillery / General of Engineers and Fortresses (L I), No. 1049/41, secret command matter, dated 2 December 1941, paragraph VII, the fortification of the stretches of coast that are difficult to approach was not included in the first construction phase. Their subsequent inclusion could only be at the expense of the other combat installations to be built in the first phase, whose construction has priority because of their tactical importance. Owing to the substantial reduction in fuel allocations—to one fifth of the quantity required, according to the figures announced so far—the construction of combat installations included in the first construction programme on account of their tactical importance has already had to be deferred. See also the report of Fortress Engineer Commander XIV concerning paragraph 2.” [Margin: Enclosure 1.]

“Almost all the islands’ artillery can deliver observed fire in front of the stretches of coast that are difficult to approach without changing position. The island commanders’ mobile reserves can be deployed to these stretches of coast in almost the same time as to the locations considered favourable for landings. Landing tanks and heavy weapons on the stretches of coast that are difficult to approach is impossible, or in some places requires a great deal of time. Uninterrupted observation of these stretches of coast is assured, and minefields have been laid on them.”

Comments of Seventh Army Headquarters: The experience emphasised above—surprise landings at locations that are difficult to approach—undoubtedly calls for appropriate defensive measures. These must primarily ensure adequate reconnaissance, observation and effective fire.

Here, strengthening the terrain is only a secondary consideration, because the natural character of the ground gives advantages over the attacker.

In the easily accessible parts of the islands, however, strengthening the terrain takes priority. Reducing construction here is all the less acceptable because the number of installations for infantry defence is already rather small. This applies particularly to Guernsey, where construction of the Mirus battery consumes most of the available building materials, etc.

See also the OKH order of 2 December 1941, paragraph VII, which calls first for the fortification of the particularly endangered locations, namely the north and northwest coasts of Guernsey, the northern part of Alderney, and the western part of Jersey.

It is therefore proposed that construction in the parts that are difficult to approach should not be included in the first construction phase.

The measures reported by LXXXIV Army Corps headquarters for protecting the parts of the islands that are difficult to approach, concerning observation, effective fire including mines, and the possibilities for deploying reserves, must suffice for the first construction phase.

Regarding Part I 1(b) of the referenced order

Commander in Chief West orders: “If an enemy landing succeeds and initially takes possession of part of an island—for example the eastern, western or northern part—the attacker must be compelled to defeat further defensive systems of considerable size, each self contained and independent of central supplies of every kind, by systematic action requiring the greatest expenditure of strength.

For these reasons, the supply installations for ammunition, provisions, fuel, etc. must be decentralised, protected, and arranged to supply individually the separate defensive systems referred to above (see Part I, paragraph 12 and Enclosures 2–17). The plans must be amended accordingly.”

LXXXIV Army Corps headquarters reports: “In view of the building material supply situation, the supply installations were planned for those parts of the islands where tunnelling is possible, because tunnelled installations require substantially fewer building materials than concrete structures. On Guernsey and Jersey, the areas around the airfields claimed by the Luftwaffe had to be left clear. The installations were also kept sufficiently distant from the bulk of our artillery positions and the likely main directions of attack, and their access roads concealed from observation from the sea. For these reasons, decentralisation of the installations is not initially possible. It must be provided for at a later date by concrete structures in other parts of the islands.

The supply installations are planned in those parts of the islands which, because of the configuration of the coast, are unlikely to be attacked from the sea and can be well defended against attack from inland.

To meet the requirement that parts of the islands cut off from the supply installations should be able to hold out for a prolonged period, it is intended to increase stocks of provisions and medical supplies in the strongpoints and batteries from 10 to 14 days. Two ammunition allocations are already stored there.”

Comments of Seventh Army Headquarters: In view of the reasons given by LXXXIV Army Corps headquarters, it is proposed to retain the present plans for the first construction phase and to provide additionally for the ordered changes in the second construction phase.

Regarding Part I 1(c) of the referenced order

Commander in Chief West orders: “The proposed total garrison strength of 36,000 men appears extraordinarily high (see Part I, paragraph 14). A review is necessary, particularly by the responsible Luftwaffe and Navy authorities for their requirements, and also of the strength allocated to supply and construction troops.”

LXXXIV Army Corps headquarters reports: “The formations listed below are considered necessary for defending the islands. Their strength corresponds to the instructions issued by OKH for the conduct of operations and the construction of defences. Their strength is calculated as follows:

I. Army

1. Headquarters: one divisional headquarters, also serving as island commander Guernsey; one island commander of brigade commander rank; one island commander of regimental commander rank; one signals battalion headquarters. Combined strength: 500.

2. Fortress troops: two regimental headquarters, 200; eight battalions, each with four mixed companies and a strength of 800, total 6,400; one company on Sark, 200; two motorcycle messenger platoons of 50 each, 100; three signals companies of 200 each, 600.

3. Field troops: one infantry regiment, partially motorised, with motorised headquarters, 13th and 14th Companies, 2,800; one engineer battalion without engineer and bridging columns, with three partially motorised companies, 500; one cyclist battalion with three bicycle companies, one motorcycle machine gun company and one heavy company, 800; one anti-tank battalion with one motorised company and two self-propelled companies, 500; one tank battalion of two companies, 400.”

4. Artillery: two regimental headquarters, 200; four heavy field howitzer battalions with twelve heavy field howitzer batteries, including [faint abbreviation] and motorised echelons for four batteries, 2,900; four motorised light field howitzer battalions, 1,900; one motorised light field howitzer battery on Alderney, 120; two assault gun batteries, 340.

Army total: 18,460.

II. Navy

Three naval artillery battalion headquarters, 150; three super-heavy batteries including anti-aircraft defence, 1,200; ten medium batteries of 15 cm guns including anti-aircraft defence, 2,500; two harbour barrier batteries of 12 cm guns, 100; additionally, three harbour commanders with personnel, 150. Total: 4,100.

The personnel strengths of naval forces to be stationed on the islands have not been included because they have not yet been fixed. Their numbers will, however, be insignificant in relation to the total garrison.

III. Luftwaffe

1. Anti-aircraft artillery: one brigade headquarters; two regimental headquarters; five battalions with fifteen heavy batteries, each with six 10.5 cm guns, and ten light 3.7 cm batteries; one searchlight battalion with four 200 cm searchlight batteries; one transport battery of three columns. Combined strength: 7,000.

2. Flying formations and ground organisation: two group headquarters with two observation squadrons, two dive-bomber squadrons and two fighter squadrons; two air stations with ground organisation. Combined strength: 2,500.

Luftwaffe total: 9,500.

IV. Construction troops

Five companies under one regimental headquarters and two battalion headquarters are required for maintaining the fortifications and carrying out minor works. Strength: 1,400.

V. Supply troops

In accordance with Part I, paragraph 12 of the tactical and technical design, the following have been included:

Three island commandants, 345; two territorial rifle companies, 320; two field police detachments, 70; one ammunition administration company, 120; one fuel administration company, 200; seven light motor transport columns, 210; three supply companies, 600; two workshop companies with two tank workshop platoons, 230; one provisions office, 40; one butcher company, 70; one bakery company, 150; two field hospitals, 150; three medical companies, 825; two motor ambulance platoons, 80; one field post office, 20; one supply staff on the mainland distributed between the ports of St Malo, Granville and Cherbourg, 70.

Supply troops total: 3,500.

Summary: I, 18,460; II, 4,100; III, 9,500; IV, 1,400; V, 3,500. Grand total: 36,960.

The excess of 960 over the tactical and technical design is explained by the inclusion of four light field howitzer battalions rather than the two calculated by 319th Infantry Division.”

Comments of Seventh Army Headquarters: On the orders of Army Headquarters, LXXXIV Army Corps headquarters has again examined the possibility of reducing the garrison strength envisaged in the tactical and technical design.

Corps headquarters reports that it cannot depart from the proposal in the tactical and technical design, since this is determined by the combat mission assigned by OKH and the fortification work ordered.

If a reduction in the proposed garrison strength is necessary, the tasks required and the fortification work must also be reduced correspondingly.

Regarding 2: The report requested by Commander in Chief West on what can be achieved by 31 July 1942 and 31 December 1942 is attached as Enclosure 1. At the same time, the report of LXXXIV Army Corps headquarters, Ia No. 1039/42, secret command matter, dated 16 June 1942, is submitted as Enclosure 2.

Regarding 3: The report of Fifteenth Army Headquarters was submitted to Army Group on 29 April 1942 under Ia / Army Engineer Commander, Pi.1, file reference 16, journal No. 274/42, secret command matter.

II. Technical report

Regarding Part II, paragraph 4 of the referenced order

Commander in Chief West orders: “Is it technically feasible and expedient to lay the water and electricity supplies in shellproof installations in conjunction with excavation of the trenches for cables to be laid with shellproof protection?”

LXXXIV Army Corps headquarters reports, on the basis of the review already carried out by Fifteenth Army Headquarters, that laying water and electrical lines together with telephone cables under shellproof protection is inexpedient.

Comments of Seventh Army Headquarters: Laying the water and electricity supply together with telephone cables under shellproof protection is technically impracticable and inexpedient, because water and electrical power adversely affect a telephone cable when laid together and ...

... continually cause disruptions to telephone communications. In the event of destruction through external causes, serious injury to personnel and damage to equipment can occur. Furthermore, the elimination of faults is made considerably more difficult and delayed.

Regarding Part II, paragraph 5 of the referenced order

Commander in Chief West orders: “Would it be expedient and quicker to enclose important existing supply installations, such as waterworks and power stations, in a manner similar to submarine pens, with bombproof roofs—pointed roofs like air raid protection towers to cause bombs to slide off—and, initially, at least splinterproof walls to be strengthened later?”

LXXXIV Army Corps headquarters reports: “Regarding paragraph 5, it is reported that pumping stations are distributed across the islands, so that the water supply remains assured even if individual stations are destroyed. The power stations—several on each island—are also situated so that a direct bomb hit is unlikely to paralyse the entire electricity supply. They also have strong anti-aircraft protection. Tactically important equipment has its own power supply. These installations will be given shellproof accommodation according to their priority. Further concrete construction for the supply installations is ruled out for the time being by the fuel situation itself.”

Comments of Seventh Army Headquarters: The statements of LXXXIV Army Corps headquarters are endorsed.

The Commander in Chief

[Signature indistinct.]

German Seventh Army records, T-312 Roll 1547, 28680/21, Army Engineer Commander. Supplied translation T312 Roll 1547 English translation DRAFT.docx. Local source scans: 0008.jpg, 0009.jpg, 0010.jpg, 0011.jpg, 0012.jpg, 0013.jpg, 0014.jpg, 0015.jpg, 0016.jpg.