Stability Concerns. A 2007 engineering paper presented at the 9th International Ship Stability Workshop in Hamburg, Germany, shows that tumblehome designs are more prone to capsizing especially went the ship is hit from behind. “The number of capsizes for the most- probable sea state 8 [30 to 46 ft waves] conditions increased drastically for the tumblehome topside for following, stern-quartering, beam and head seas,” the report reads. “The capsize risk for the tumblehome geometry had a greater increase for small increases in KG [center of gravity] than the flared topside...Dynamic Stability of Flared and Tumblehome Hull Forms in Waves.pdf
BMD Lack. One thing the ship won’t be able to do is defend against ballistic missile attacks—which is one of the reasons the Navy ditched the design in favor of the older Burke-class design. While the ship’s AN/SPY-3 radar is capable, it does not operate in the proper frequency band for that mission.
That’s a major deal. There’s a rising threat of ballistic missiles in the West Pacific, where China is deploying such weapons [CSS-5 mod 5 DF-21D ASBM]. Ultimately, the changing threat and enormous price tag doomed the program and only three ships will be built at exorbitant cost.
History May Repeat Itself
USATODAY.com - World War II Pacific typhoons battered U.S. Navy
Two typhoons did major damage to the U.S. Navy’s Third Fleet in the Pacific, commanded by Adm. William Halsey late in World War II. The first hit on Dec. 17, 1944. This typhoon, which was informally named "Cobra," [inspiration for the Caine Mutiny] had sustained winds estimated at 145 mph and probable guest to 185 mph. Three destroyers capsized and sunk, but a few men on them survived to be picked up by other ships. Numerous other ships were heavily damaged and 146 airplanes were destroyed. The storm killed 778 men. The second hit the Third Fleet with 50- to 60-foot seas, sustained winds of about 115 mph and gusts probably up to about 150 mph on June 2 and 3, 1945 east of Okinawa. This typhoon damaged 33 ships and destroyed 76 airplanes, mostly on the flight or hanger decks of aircraft carriers after the airplanes broke free of the chains holding them down. The storm killed six men on U.S. ships. It died at sea without ever hitting land.
Zumwalt-class destroyer - Wikipedia, the free encyclopedia
Tumblehome wave piercing hull
A return to a hull form not seen since the Russo-Japanese War in 1905, the Zumwalt-class destroyer reintroduces the tumblehome hull form. Originally put forth in modern steel battleship designs by the French shipyard Forges et Chantiers de la Méditerranée in La Seyne in Toulon, ...On the down side, the tumblehome battleships experienced losses in watertight integrity and/or stability problems (especially in high speed turns).[54] 21st century tumblehome is being reintroduced to reduce the radar return of the hull. The inverted bow is designed to cut through waves rather than ride over them.[49][55]
Radar BMD - TSCE software limits
A study to place the AMDR on a DDG-1000 hull was done with the 22-foot (6.7 m) aperture primarily for Ballistic Missile Defense (BMD) purposes. In that the DDG-1000 does not have an Aegis combat system, as does the DDG-51 class ships, but rather the Total Ship Computing Environment (TSCE) Infrastructure, the Radar/Hull Study stated:
...that developing a BMD capability "from scratch" for TSCE was not considered viable enough by the study team to warrant further analysis, particularly because of the investment already made in the Aegis program. The Navy concluded that developing IAMD software and hardware specifically for TSCE would be more expensive and present higher risk. Ultimately, the Navy determined that Aegis was its preferred combat system option. Navy officials stated that Aegis had proven some BMD capability and was widely used across the fleet, and that the Navy wanted to leverage the investments it had made over the years in this combat system, especially in its current development of a version that provides a new, limited IAMD capability.[67]
Phisical Psience ΦΨ - US NAVY - DDG 1000, Tumblehome Hull - Zumwalt Class Destroyer
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Defense News: Will DDG-1000 Destroyers Be Unstable?
“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. Its long, angular “wave-piercing” bow lacks the rising, flared profile of most ships, and is intended to slice through waves as much as ride over them…”“…Brower explained: “The trouble is that as a ship pitches and heaves at sea, if you have tumblehome instead of flare, you have no righting energy to make the ship come back up. On the DDG 1000, with the waves coming at you from behind, when a ship pitches down, it can lose transverse stability as the stern comes out of the water – and basically roll over.”
“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. Ken Brower, a civilian naval architect with decades of naval experience was even more blunt: “It will capsize in a following sea at the wrong speed if a wave at an appropriate wavelength hits it at an appropriate angle”… “
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