31 October 1944 Part 8

Continuation: berthing memorandum; Cherbourg harbour assessment

18:00

Weather: wind north-east, force 5–6; sea state 2–4; visibility 6 nautical miles; cloud 9/10; cloud base 1,000 metres.

Since 10 October an investigation had been conducted into how far destruction of Cherbourg’s moles and harbour installations affected use of the port in bad weather. To supplement visual reports made when conditions were favourable, the Alderney naval radar stations were also employed when visibility was below 10 nautical miles and sea state 3–4 or higher.

The summary in Annex 3, compiled with allowance for wind, sea and visibility, records observed results and includes both warships and merchant vessels among arriving and departing traffic.

For days with winds of force 6 or more, the observations showed: (1) in onshore north-west or north-east weather, Cherbourg had more departures than arrivals on four of six observed days — 23, 24, 28 and 30 October. On 24 October, during a northerly gale, the ratio of 22 departing vessels to five arrivals most clearly indicated impairment of the harbour’s berthing capability. Only on 27 October were there slightly more arrivals; on 21 October the figures were equal. (2) In offshore south-west to south-east weather, more ships departed than entered on the three days for which records existed — 11, 12 and 13 October — but there were no revealing large differences.

T-1022 Roll 2423, PG 37998, Commander of Sea Defences, Channel Islands. Source scan 0030 — original page 222