Editing Multihull (section)

== Performance ==
Each hull of a multihull vessel can be narrower than that of a monohull with the same displacement<ref>Most ships (excluding hydrofoils and planing hulls) stay afloat by displacing their weight in water.  A multihull can divide that displacement between multiple, narrow hulls.  A monohull must be deeper, longer, or wider to displace the same amount of water.  A single long, deep hull would be unstable and hard to maneuver, so monohulls are almost always wider than the individual hulls of a multihull vessel.</ref> and long, narrow hulls, a multihull typically produces very small bow waves and [[Wake (physics)|wake]]s, a consequence of a favorable [[Froude number#Ship hydrodynamics|Froude number]].<ref>The Froude number of any hull is calculated by <math>\mathrm{Fn}_L = \frac{u}{\sqrt{gL}},</math> where {{math|''u''}} is the relative flow velocity between the sea and ship, {{math|''g''}} is in particular the [[Gravitational constant|acceleration due to gravity]], and {{math|''L''}} is the length of the ship at the water line level, or {{math|''L''<sub>wl</sub>}} in some notations. It is an important parameter with respect to the ship's [[drag (physics)|drag]], or resistance, especially in terms of [[wave making resistance]].</ref><ref>{{Citation
 | first1 = Park
 | last1 = J.W.
 | first2 = Kim
 | last2 = J.J.
 | first3 = Kong
 | last3 = D.S.
 | editor-last = Wu
 | editor-first = You-Sheng
 | editor2-last = Zhou
 | editor2-first = Guo-Jun
 | editor3-last = Cui
 | editor3-first = Wei-Cheng
 | title = Numerical computation of ship's effective wake and its validation in large cavitation tunnel
 | series = Practical Design of Ships and Other Floating Structures: Eighth International Symposium - PRADS 2001
 | year = 2001
 | pages = 1422
 | volume = 1
 | publisher = Elsevier
 | url = https://books.google.com/books?id=ZHi3uG6ZgpUC
 | isbn = 9780080539355
 }}</ref><ref>{{Cite web|url=https://www.usna.edu/NAOE/_files/documents/Courses/EN400/02.07%20Chapter%207.pdf|title=Resistance and powering of ships|last=Instructors|website=US Naval Academy|pages=7–9|access-date=2019-03-09|archive-date=2020-04-08|archive-url=https://web.archive.org/web/20200408215122/https://www.usna.edu/NAOE/_files/documents/Courses/EN400/02.07%20Chapter%207.pdf|url-status=live}}</ref> Vessels with beamy hulls (typically monohulls) normally create a large bow wave and wake.  Such a vessel is limited by its "hull speed", being unable to "climb over" its bow wave unless it changes from displacement mode to planing mode. Vessels with slim hulls (typically multihulls) will normally create no appreciable bow wave to limit their progress.

In 1978, 101 years after catamarans like ''[[Amaryllis (catamaran)|Amaryllis]]'' were banned from [[yacht racing]]<ref name="ym">{{cite magazine |url=https://books.google.com/books?id=F_NOsIXtd14C&dq=%22Jay+Kantola%22&pg=PA84 |author=Randy Thomas |date=June 1985 |pages=84–87 |title=Multihulls Discovered: Part 1: Their origins, myths, magic, mana... and caveats that go along with these craft that have evolved from ancient heritage |magazine=[[Yachting (magazine)|Yachting]] |access-date=January 7, 2015}}</ref><ref name="Spirit">{{Cite web
|url=http://www.ulstc.org/Herreshoff.html
 |title=The Spirit of the Times, November 24, 1877 (reprint)
|author=L. Francis Herreshoff
|publisher=Marine Publishing Co., Camden, Maine |archive-url = https://web.archive.org/web/20080124161749/http://www.ulstc.org/Herreshoff.html |archive-date = 2008-01-24}}</ref> they returned to the sport. This started with the victory of the trimaran ''[[Olympus Photo]]'', skippered by Mike Birch in the first [[Route du Rhum]]. Thereafter, no open ocean race was won by a monohull. Winning times dropped by 70%, since 1978. Olympus Photo's 23-day 6 hr 58' 35" success dropped to Gitana 11's 7d 17h 19'6", in 2006. Around 2016 the first large wind driven foil-borne racing catamarans were built. These cats rise onto foils and T-foiled rudders only at higher speeds.{{citation needed|date=March 2019}}