Talk:Extreme clipper

This article is extremely informative. But it does not address the question: Why deadrise was so important to clipper designers? I have read nearly all the books by David MacGregor, I have also read the book "search for speed under sail" by chapelle, This question was never answered in any of these books. They discuss page after page on how much a certain ship have deadrise, but never why.

It is well known that deadrise slightly increases the hydrodynamic resistance. So, lessening the resistance cannot be the answer. My guess is, it increases the ship's capability of going against the wind. But this also does not hold much water: clippers had square rig, so they had very limited capability of beating to wind, irrespective of the hull form.

Can anybody who knows the answer enlighten us?

Also, is it known how much a clipper can approach to wind? How much for a "normal" merchant ship? 88.238.217.218 (talk) 19:58, 17 January 2012 (UTC)mehmet

Rewrite needed
This article is sourced with Arthur H Clark's The Clipper Ship Era and a number of contemporary newspaper reports. The newspaper articles can be regarded as primary sources, written largely by people with no particular expertise in naval architecture. Maritime historians have found many such articles to be error prone.

Clark is a problematical source. His book contains some puzzling blunders - for instance on page 320 he talks about the tea clippers: "The tea trade in the early '60s was comparatively small and did not require many vessels. ...... Only 25 or 30 of these vessels were built from first to last". This is a bizarre statement, when at least 60 tea clippers sailed in the 1867 to 1868 tea season, with similar numbers in other years in this decade. It is worth noting that the tea season I have picked as an example is before the final boom in building tea clippers (Thermopylae, Cutty Sark, etc., etc.) Clark's assessment of whether or not a vessel is an extreme clipper appears to be based largely on passage times, with some comment on hull form. Maritime historians such as Howard I. Chapelle prefer to use precise measures like the Prismatic coefficient, and David R MacGregor, whilst agreeing with Chappelle, additionally uses (more pragmatically) his coefficient of under deck tonnage. Both take a rigid naval architectural view of the measurement of hull shape. I suggest that much of that technicality might be lost on Clark. Whilst Clark appears to be correct in much of what he says, there are so many errors that his work cannot be used in isolation as the basis or an article.

This article therefore requires a total rewrite based on authoritative sources. Chapelle, with his Search for Speed Under Sail and MacGregor's wide range of books, but particularly Fast Sailing Ships would be a start. ThoughtIdRetired (talk) 20:10, 13 July 2021 (UTC)


 * It is worth adding that the article's statement: "The last extreme clippers were built in 1855" is totally wrong, as it ignores the tea clippers built in the second building boom of that type. The most extreme of these include Thermopylae, Leander, Ariel, Cutty Sark and several others. Ships such as Scawfell (1858) would also make the grade as an extreme clipper - and I would guess a good number of other examples could be found. ThoughtIdRetired (talk) 20:29, 13 July 2021 (UTC)