The YD-40, top, with a more traditional keel, appears in the 3rd edition, while the contemporary YD-41, designed for the 4th edition, was built, sailed, and photographed for the 5th.
For decades, Principles of Yacht Design (PoYD) has been the gold standard for practitioners in this line of work. Now in its 5th edition, the book has grown from 352 pages to 400 and from $60 to $90 in retail price, although it can be ordered from Amazon for $64.99. Anyone considering purchasing the 5th edition should be aware that the preface and dust jacket imply it is wholly revised, which is not completely correct. For instance, the YD-41 design example was not developed for this new edition as stated. Rather it is a carryover from the 4th but was built, sailed, and photographed for the 5th. YD-41 is state of the art with its high-aspect-ratio fin keel and a torpedo bulb extending forward of the fin, and twin rudders consistent with the wide stern. It results in a modern hullform that is not very practical for sailing in waters with a high density of crab pots or lobster traps, which could result in snags or wraps. Those interested in designing a hull with a more traditional keel should acquire a copy of the 3rd edition, featuring the YD-40 with its moderate-aspect-ratio fin and a swept-back leading edge.
The increase of 48 pages in the new edition is primarily due to the 35-page chapter on foiling. On the subject of powerboat design, there is a new chapter titled High-Speed Hydrodynamics, which is limited to planing hullforms. For further inquiry into any of the topics, PoYD helpfully mentions numerous sources and offers a reference section at the end that lists the 96 works cited in this edition (up from 71 in the 4th edition), ranging from current studies back to the books of L. Francis Herreshoff and Frank Kinney. The authors are to be congratulated in expanding PoYD and keeping it up to date.
Principles of Yacht Design, by Lars Larsson, Rolf E. Eliasson, and Michal Orych. Adlard Coles, 400 pp., $90, ISBN: 978-1-4729-8192-9.
