Parece-me um Blackburn Skua, mas esse era britânico...
Não, é o sucessor do "Kate", o Nakajima B6N "Tenzan". Este é um B6N2 capturado depois da rendição do Japão em testes pela US Navy.
É aquele pseudo-país o Principado de Sealand?
Maunsell also designed forts for anti-aircraft defence. These were larger installations comprising seven interconnected steel platforms, five carried guns arranged in a semi-circle around the control centre and accommodation — the seventh set further out than the gun towers was the searchlight tower. Maunsell Sea FortsThree forts were placed in the Mersey.A further three were sited in the Thames estuary:Nore (U5), Red Sands (U6) Shivering Sands (U7). Each of these AA forts carried four QF 3.75 inch guns and two Bofors 40 mm guns. During the war the forts shot down 22 aircraft and about 30 flying bombs. They were decommissioned by the MoD in the late 1950s.