19 June 1943

19 June 1943 Assessment of the defensibility of the west coast Annex 175

LXXXIV Army Corps, Ia 1244/43, top secret, to Seventh Army. Major enemy landings on the west coast of the Cotentin peninsula have hitherto been considered unlikely. This assessment rested on the following considerations. The flanking threat from the Channel Islands, especially Alderney, was regarded as sufficiently strong to prevent large naval formations passing through the strait between Cap de la Hague and Alderney. The distance from embarkation ports on England’s south coast is one hundred nautical miles, so commando operations using transport ships could not evade reconnaissance during the short summer nights. Water depths and offshore reefs would oblige transports to remain offshore and transfer troops into small landing boats. Tidal currents of up to six knots would greatly hinder those boats.

The existing force deployment, allocation of anti-landing weapons and plans for permanent construction reflect that assessment. Six companies defend the 110-kilometre west front from Cap de la Hague to the corps boundary. Four belong to the Georgian infantry battalion, holding the eighty-eight kilometres from south of Vauville Bay to Authie. A reinforced grenadier battalion with improvised motor transport and the operational formations of Mobile Brigade 30 stand behind the sector as corps reserves. Artillery support is possible only in front of Vauville Bay. South of the bay, the Georgian battalion’s eighty-eight-kilometre sector has one light, five medium and two heavy antitank guns and seven anti-landing guns—about one gun per six kilometres. No permanent construction is planned at all between Vauville Bay and the corps boundary.

This assessment of the danger to the west coast can no longer be maintained. The islands’ flanking effect can operate only through their long-range artillery against enemy warships and transports, or through German naval forces stationed there. In favourable visibility, artillery can cover the strait between Cap de la Hague and Alderney. Guernsey’s contribution is limited to Battery Mirus, which can just reach at its extreme range. Because of the great distance, very difficult observation and available ammunition expenditure, Jersey’s artillery can be rated only as providing harassing fire of limited duration; even in favourable circumstances this reaches only to within eight kilometres of the coast. No significant German naval forces are present in the islands area.

Enemy air superiority during the first days of any operation would allow the flanking threat from the Channel Islands, or at least Alderney, to be neutralised even if the batteries had strong antiaircraft protection. There is no doubt that the enemy could very quickly engage and tie down each island from the sea with superior heavy naval forces. Use of smoke must also be expected.

According to the latest information, the enemy’s landing craft can travel under their own power from the embarkation ports and reach the coast in six to seven hours. Their speed—up to eighteen knots for L.C.I.—makes tidal drift insignificant. At high water, offshore reefs and rocks are no longer insurmountable obstacles to the new shallow-draught craft. Pilots with local knowledge must be assumed. The craft carry artillery up to 4 cm and mortars up to 10.7 cm, allowing them to engage our anti-landing weapons, which have only field protection, from the sea.

With these vessels, the enemy could land approximately one division with tanks, light landing artillery and heavy weapons. Such forces could eliminate resistance-nest garrisons, spaced on average four to six kilometres apart, and penetrate inland with their mobile elements, possibly on a broad front, before the reserve battalion’s counterattack became effective. If the landing were combined with airborne troops, part of our reserves would initially be tied down as well.

The landing might be a powerful independent operation, for example a diversion, or part of larger airborne and seaborne landings elsewhere. It is particularly necessary to reckon with this because British instructions repeatedly advocate landing where the opponent least expects it; see also Commander-in-Chief West’s Fundamental Observations No. 26.

The navy’s previous view that the west coast was not endangered by landings did not take account of the enemy’s now improved opportunities. Once the 389th Division is fully formed, and provided it remains in its present area as army-group reserve, a prolonged enemy success is not expected. Even then, landing and penetration inland cannot be prevented: six companies are too weak a garrison, deployed artillery is lacking, and heavy anti-landing weapons of every kind are particularly deficient.

Reinforcement of the 709th Division by a third grenadier regiment and an artillery battalion will remedy this weakness only if the corps boundary is not extended southward and the Georgian infantry battalion remains with the corps. Without it, adequate coastal manning and the necessary reserves are impossible. LXXXVII Army Corps makes a similar assessment of the adjoining west-coast sector on either side of Granville and in Mont-Saint-Michel Bay.

Corps headquarters therefore requests: rapid delivery of a third grenadier regiment and an artillery battalion to the 709th Division; retention of the Georgian infantry battalion; retention of the present southern corps boundary; ten additional anti-landing guns, ten 5-cm tank guns and five 7.5-cm antitank guns for the Georgian battalion’s current sector; retention of Heavy Artillery Battalion 450 as corps reserve; and allocation of permanent artillery and infantry works following further reconnaissance. Distribution: Seventh Army; 709th Division and LXXXVII Army Corps for information; war diary; draft.

Original source image | Source PDF page 584 | Entry dated 19 June 1943

T-314 Roll 1604, T314_R1604_English_Translation.docx. 19 June 1943 | Source PDF pages 583–587. Selected island-related text; document or report date governs placement.