This painting forms part of Norman Wilkinson's ‘The War at Sea’ series, depicting the work of the Royal Navy, Merchant Navy and RAF Coastal Command, of which 53 were exhibited under that title at the National Gallery in 1944, and the full set of 54 presented by him to the nation via the War Artists Advisory Committee (this item's WAAC number being LD 4323). For details of the slightly complex history of the acquisition see BHC1590, the start of the set by modern NMM catalogue number. Note that the present picture was the only one not included, possibly for space reasons, in the set's initial 1944 exhibition at the National Gallery and also that following painting by WAAC number( 'Convoy', LD 4324) is the one not in the NMM holding: it was allocated to the Royal United Service Institute, London, in 1947 and remains there.