In addition, the Dutch had secured options for four more, she said.

Built of marine aluminium, the boats are almost identical to the three tough SWATH tenders Duhnen, Dose and Wangeroog which have been in pilot operation in German waters, mainly the Elbe region, for up to five years. They are 14.26m wide, draw 2.7m and have speeds of 18 knots.

Propulsion is via two MTU 12V 2000M70 diesels per ship of 788kW each, operating across two Reintjes WVS 430/15 gears onto two fixed Schaffran propellers. The two generators and e-motors on each ship are from Interschalt.

A&R has drawn attention to the excellent sea holding and manoeuvrability of SWATH tenders, which can operate in waves of up to 3.5m.

The Dutch newbuildings will serve incoming vessels off the Hook of Holland, and at Ijmuiden and in the Schelde Estuary and take over from existing pilot boats and their dinghies.

Rare criticism of the SWATH pilot boat concept came meanwhile from the German pilot group Weser 11/Jade, which said it was planning a mono-hull pilot system. The head of the German pilot group said the Weser/Jade area was a different kettle of fish to Holland and the Elbe, without withdrawal possibilities and that SWATH vessels were not suitable and also too costly.

He criticised German authorities who, he said, 'would like to plaster the coast full with SWATH tenders'.