Over the past 45 years I have had the pleasure of designing an unusually wide variety of boats of all sizes – both sail and power-driven (see https://nigelirens.com/), but right now we are concentrating on spreading the word about a particular kind of power-driven boat – the development of which has been an on-going passion of ours since 2003.

These designs are characterised by the fact that their hulls are unusually Long for their Displacement. From the outset we therefore adopted the term ‘LDL’ (‘Low Displacement/Length ratio) to identify this kind of vessel.

In the case of the ‘LDL’ hull our clear objective has always been to optimise a range of speeds that lie anywhere between slow speed (the easy bit…) up to ‘swift’ speeds up to about 12-14 knots – beyond which planing-hulled designs will be more appropriate – especially if these speeds are needed for much of the time afloat.

Totnes, UK