A minor point - you wrote "The three RN escorts are painted in similar schemes ...", but the two destroyers appear (from what little can be seen) to be camouflaged in the Special Emergency Fleet Destroyer Scheme - for example, the photo at http://www.iwm.org.uk/collections/item/object/205161785 shows OPPORTUNE in this scheme the previous year. CALDER wears the scheme commonly worn at commissioning by most Buckley (not Evarts) class ships transferred to the RN.
: I came across this image at the US National
: Archives on a recent trip, which is cropped
: from a larger image. It showed an EVARTS
: class DE alongside USS PRAIRIE (AD-15).
: After I scanned this transparency, I
: realized that the DE was one of the RN
: lend-lease units, HMS CALDER (K.349). USS
: PRAIRIE was the USN station repair ship at
: Argentia until 23 September 1943. So this
: photo dates before then. I remembered that
: I had scanned some of USS PRAIRIE's War
: Diaries when I was researching HMS
: VICTORIOUS arrival at Argentia in September
: 1943. When I looked at USS PRAIRIE's War
: Diary it noted that HMS CALDER arrived at
: Argentia on her way to the UK from the USA
: on about 20 September 1943. So at that
: point, this photo had to date roughly from
: 20 to 23 September 1943.
: What is barely visible is that there is are
: TWO RN destroyers tied up between HMS CALDER
: and USS PRAIRIE. Again the War Diary enter
: for 19 and 20 September 1943 came in useful.
: It said that HMS OPPORTUNE AND HMS OBDURATE
: had arrived at about noon on 19 September
: and moored at buoys. Then early on 20
: September they moved and moored to USS
: PRAIRIE, with HMS OPPORTUNE next to USS
: PRAIRIE and HMS OBDURATE outboard of HMS
: OPPORTUNE. HMS CALDER then moored outboard
: of HMS OBDURATE. At 0835 USCG 707 moored to
: the dock ahead of USS PRAIRIE, which can be
: seen in this photo.
: The War Diary further states that all three
: of these RN escorts departed with HMS
: VICTORIOUS (which had only arrived on 19
: September with two USN Flush-Decker escorts)
: just before noon that same day headed back
: to the UK.
: So this photo firmly can be dated as being
: taken on 20 September 1943, sometime after
: 0835 and before noon.
: The three RN escorts are painted in similar
: schemes and USS PRAIRIE is painted in MS 18
: (5-N hull and 5-H topside) that is well
: faded in this photo.