Thursday, December 10, 2015


This is coolbert:

Critics of the tumblehome design of the DDG1000 Zumwalt abound:

1. "Will DDG-1000 Destroyers Be Unstable?"

“Is New U.S. Destroyer Unstable?”

"Are the critics prisoners of their preconceptions re: what ships are 'supposed' to look like, or sounding an early alarm before a very expensive ship and its crew are lost to Mother Nature rather than enemy fire?"

“Nothing like the Zumwalt has ever been built. The 14,500-ton ship’s flat, inward-sloping sides and superstructure rise in pyramidal fashion in a form called tumblehome."

“At least eight current and former officers, naval engineers and architects and naval analysts interviewed for this article expressed concerns about the ship’s stability . . .  'It [Zumwalt] will capsize in a following sea at the wrong speed if a wave at an appropriate wavelength hits it at an appropriate angle'… “

"Following sea . . . wrong speed . . . appropriate wavelength . . . appropriate angle".

And such an occurrence will happen how often?

2. "Instability Questions About Zumwalt Destroyer Are Nothing New"

"As the US Navy's newest ship puts to sea for the first time, old questions are resurrected"

"WASHINGTON — The advanced destroyer Zumwalt (DDG 1000) is scheduled to put to sea next week to begin a series of sea trials."

"The Zumwalt and her two sister ships are built with a tumblehome hull, where the sides slope inward rather than outward or at a straight vertical as in most ship designs. The configuration, part of the ship’s low-cross section or stealth characteristics, is reminiscent of some designs of more than a century ago, but the DDG 1000 takes tumblehome to a new extreme. Essentially, no one has ever been to sea on a full-sized ship of this type."

YES and NO! Some French warships of the Pre-Dreadnought era incorporated the tumblehome hull. EVEN FRENCH NAVAL ARCHITECTS PREFERRED THIS DESIGN! More correct to say that NO modern warship uses the tumblehome hull!

"Following sea . . . wrong speed . . . appropriate wavelength . . . appropriate angle".

A prudent commander, observing such conditions, will be alert to same and take measure to prevent his vessel from foundering? I might think so.


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