Four days later, Allied Expeditionary Air Force HQ gave its reply:
Extreme importance of denying air R/C to enemy fully appreciated. Frequent saturation of area at all heights by friendly aircraft makes tracking and identification complex and not completely reliable. Lack of need to make penetration [inland] also reduces time available for interception. In spite of these difficulties every effort now being made to prevent him reconnoitring concentrations in Isle of Wight area prior to “Overlord” and during exercise “Fabius”. In spite of all measures being taken however, complete immunity from enemy air R/C cannot be guaranteed.
The German naval situation report for the day noted that:
The Luftwaffe reconnoitred the various harbours in the Thames Estuary. Their occupancy is not out of the ordinary and suggests no special massing of landing vessel capacity. The photograph of Falmouth from 27 April shows an escort vessel 10 LST, 15 LCT or various sizes, 20 LCI, 23 small landing boats, 2 auxiliary landing boats, 3 steamers, 28 presumed landing bridges and various small vessels.
The Japanese Naval Attaché reported that “reconnaissance of Thames [on the 21st, presumably] showed nothing fresh. Landing operations being prepared for most part on West Coast of Britain. Speeches and broadcasts to French people all give impression second front close at hand”. An early morning mission (by 5.(F)/123?) was recalled and ordered to land at Denain-Prouvy, close to the Franco-Belgian border. Meanwhile in the Western Channel, NAG 13 dispatched a Rotte to Lyme Bay at 0745 and a second to the seas south of Plymouth at 1315. The latter mission reported an eastbound convoy 20 km south Rame Head, seven merchant vessels of 3–5,000 tons with a single escort. Allied fighters spotted on a reciprocal course did not attack although German radar had warned that they were looking for the interlopers. It appears to have been this shipping report which prompted the dispatch of E-Boats to Lyme Bay after dark (although they had already been active along the Channel convoy routes for several nights).
In the early hours of the 28th, the Germans were able to engage Convoy T-4 which was one element of Exercise Tiger, a practice landing at Slapton Sands in Devon. The E-Boats sank two LSTs and damaged two more, causing the deaths of almost 1,000 men and wounding 200 more. Analysts at Bletchley Park later noted that:
During a sortie by E-boats against LSTs off Portland [Kommando der Schnellboote] felt it necessary to report that LSTs sighted … did not justify the assumption that landing operations had begun …
The Kriegsmarine diary has this:
During the night 27–28/4, 5. and 9. S-Flotillas operated against a convoy in Lyme Bay and sank with certainty a landing ship (4,600 GRT), 1 landing ship (3,000 GRT) and 1 steamer (1,500 GRT) and torpedoed a destroyer and a landing vessel (200 GRT). All boats returned to Cherbourg.
Notably more active, NAG 13 sent pairs of fighters to Plymouth (0635–0759) and Penzance (0931–1046), two more Rotten made overwater sorties late in the afternoon; more unusually a group of three was up from 1506–1604. The Penzance mission was abandoned after an hour owing to cloud, the Bf 109s returning to base. There was no action reported elsewhere in the Channel but the coverage of Plymouth proved conspicuously successful. At 0707, radar tracked aircraft 80 km south of the city, heading north to make landfall at Stoke Point. In the harbour they were able to photograph three battleships, seven cruisers, 17 destroyers, two monitors, six escorts, 11 LST, 11 small landing craft, 13 freighters and numerous small craft. At RAF Mountbatten, Plymouth,there were 10 Sunderland flying boats. As a bonus, they were able to report 10 eastbound merchant vessels in the Channel. Although the Messerschmitts had been attacked from ahead by two fighters at very low level, neither side had opened fire. Acting on the photos obtained, 101 Luftwaffe bombers raided Plymouth on the night of the 29/30th.
A renewed attempt to get coverage of Penzance succeeded, two NAG 13 Bf 109s leaving Dinard at 1400 and an hour later photographing the coast from Gunwalloe to Newlyn from 7800 m. Only a handful of small ships was in port at Penzance but Newlyn accommodated 45 small craft and auxiliary landing craft; on the return flight they saw a rubber dinghy with about 10 dead bodies aboard. Why these smaller Cornish ports were prioritised over the major (and as yet unphotographed) docks and anchorage of nearby Falmouth and Carrick Roads is far from obvious. During an evening mission, an aircraft was warned by its controller of a “sailing boat” south of the Isle of Wight; the Y-Service took this to be some kind of code word.
On Guernsey, 1./NAG 13’s Fw 190 F-1, W.Nr. 013 0392, was 70% damaged in a crash and handed over to the local salvage unit.
Late in the afternoon, Stab NAG 13 mounted two overwater reconnaissances of two Bf 109 each without seeing any shipping. Both formations reported that defending fighters had been searching for them. FAG 123 also sent up a Bf 109 Rotte during the evening, with a similar absence of results; again the British overheard an “immediate recall” message.
As the month ended, Stab NAG 13 reported recently taking over five Bf 109s: W.Nr. 160876 (NT+_B), 161441 (NP+UL), 162067 (RW+DP) and 15648 (DR+CN), all with Rb 12.5/7 x 9 cameras; and W.Nr. 161429 (NP+ZC) which lacked both MW 50 boost and an Identification Friend or Foe set. Meanwhile, 4.(F)/123 was asking for a new DB 605 engine for Bf 109 G-4 W.Nr. 19401. An unnamed Staffel received Bf 109 G-5 W.Nr. 110346 from Guyancourt, this one properly fitted out with its radio gear, GM 1 boost, Rb 50/30 and an MG 151/20 cannon.
Assessing the month’s efforts, the British attributed the “particularly striking” increase in NAG 13’s sortie rate to the recent arrival of the 3. Staffel on the Channel coast. Meanwhile, 3.(F)/122’s night security reconnaissance had become “a routine operation” but had failed to secure any significant results.
to be continued …