Sir, – In the recent Naval Review, your Chairman states, “there will be no planned conventional replacement for the Type 45.” But surely this does not mean to imply that the Type 45 is itself a ‘conventional’ design. The destruction of our latest Air-Defence Destroyer, HMS Sheffield, by a single air-launched Exocet missile, signalled the end of the slender ‘destroyer’ hull-form that had dominated warship hulls below cruiser-size for a century. It was suddenly overtaken by events, as I have sought to explain in the text and Appendices of my recently-published book The Falklands Factor – the Bat…