Table of Contents (Click to Navigate)
- A Brief Primer On Stability
- WATCH: A Sail Boat Stabilize Itself At Launch
- WATCH: Raw Video of Badën’s Capsizing
- The History of Northern Marine
- Official Statement
- Extra Photos and Videos
A Brief Primer On Stability
A floating vessel is considered “stable” if it tends to remain in an upright position, or return to an upright position after being heeled by an external force, whether wind, or sea or something else. Hydrostatic (buoyant) stability is the result of two interacting forces, gravity and buoyancy.
Gravity pulls a vessel down into the water, while buoyancy works to push it up out of the water. In a heeled vessel that displays positive stability, these two forces are located at a distance from one another, and they form a couple that works to return the vessel to a position of upright equilibrium.
Gravitational force is related to a vessel’s total mass, which by mathematical averaging, can be considered concentrated at a single point known as the vessel’s center of gravity (CG). This point is located in three-dimensional space by longitudinal, transverse and vertical coordinates. When considering a hull’s transverse stability, we are concerned primarily with the vertical coordinate of the center of gravity, commonly designated as VCG.
Buoyancy is generated by the pressure of the water surrounding the submerged portion of a vessel’s hull. Put crudely, the water displaced by the submerged volume of the hull stubbornly attempts to reoccupy the space from which it has been displaced and thereby applies an upward force to the hull. The sum total of this buoyant force is considered to be concentrated at the geometric center of the vessel’s submerged volume, and is known as the center of buoyancy (CB).
Again, this point is located in three-dimensional space by three coordinates: longitudinal, transverse and vertical. When considering transverse stability, the most important of these is the transverse coordinate, commonly designated as TCB.
It is important to understand that, barring mishaps like tanks rupturing or major weights tearing loose, the CG remains fixed when a vessel heels. However, while submerged volume remains constant when a vessel is heeled, the shape of that submerged volume does not. Instead, as the vessel heels over, the three-dimensional shape of that submerged volume changes, and the three-dimensional coordinates of the geometrical center of submerged volume shift. In particular, the CB moves outward from the vessel’s centerline toward the downward heeled side.
As a result, a force couple develops between the downward gravitational force centered at the CG, and the upward buoyant force centered at the CB. This force couple works to return the vessel to an upright position of stable equilibrium.
Figure 1 of the top image illustrates how the CG and CB are aligned, cancelling out one another when a vessel is in upright equilibrium. Figure 2 shows how, as the vessel heels, the position of the CG remains fixed but the changing shape of submerged volume results in a shift of the CB outward toward the heeled side. As long as the relative positions of the CG (which does not shift) and the CB (which does shift) remain such that the force couple formed between them works to right the vessel, she is within her “range of positive stability.”
However, as shown in Figure 3 of the top image, if external forces continue to heel the vessel further, there comes a point at which the relative positions of the CG and CB reverse, with the result that the force couple formed works not to right the vessel, but to capsize her.
The point at which a vessel is beyond her maximum range of positive stability is usually delineated as a maximum angle of heel, in degrees from upright. Thus, if a vessel reaches her maximum range of positive stability at, say, a 70-degree angle of heel, when she heels past 70 degrees, she will lose any inherent tendency to return to an upright position.
Adding ballast low down in a vessel, along her keel, lowers her CG and increases the force of her righting couple and her range of positive stability. That is why the question of whether sufficient ballast had been installed in Badën at time of launch is pivotal.
The History Of Northern Marine
Although New World Yacht Builders is not a large shipyard by world standards, the Northern Marine marque is without doubt a major one on the custom yacht building scene. Northern Marine was founded in the mid-1990s by Richard “Bud” Lemieux, who previously had built yachts and small commercial vessels for more than two decades at Delta Marine in Seattle.
Beginning with Spirit of Zopilote, which Northern Marine completed for well-known TV producer Bruce Kessler in 1997, Lemieux successfully built and launched some 28 handsome and exceptionally rugged yachts, from 35 to 152 feet LOA, before he left the firm in 2006. Many of these were expedition yachts in the genre of some of the small, very stout fishing trawlers that Bud had built during his Delta years; but several, like Lia Fail, were solidly in the class of highly styled and finished luxury motor yachts. I was aboard the Lia Fail (renamed Sorcha) about a year and a half ago, and I can attest personally to the fact that she was built and finished to world-class standards.
While the Northern Marine marque has maintained pretty continuous visibility in the custom yacht market for nearly two decades, it has actually been owned and/or used serially by a chain of legally distinct companies whose ownership, although sometimes overlapping, has changed over time.
Richard “Bud” Lemieux formed NM, Inc., in 1995, and registered to do business under the trade name Northern Marine. In 2003, Lemieux took some partners into the business. Then, in 2006, Lemieux left the Northern Marine operation. Four years later, in May 2010, Northern Marine Co., LLC filed for voluntary Chapter 11 bankruptcy, from which it did not emerge. And at that time, Lemieux reacquired ownership of the marque and various hard assets of Northern Marine from bankruptcy. Around that time, Andy McDonald formed New World Yacht Builders LLC and reopened doing business as Northern Marine, using hard assets leased from Lemieux.
According to a June 2011 press release by New World, it was the beginning of “a new generation at Northern Marine.” The press notice explained that the owner of an in-process 64-footer that was caught up in the 2010 bankruptcy of Northern Marine Co., LLC had contracted with the new firm to complete his yacht. The release also heralds the fact that the new firm had contracted to build an 80-foot expedition yacht for an East Coast owner, and a 90-footer for the owner of the Northern Marine 74 Atlas. To everyone, it appeared that custom yacht building in Anacortes was again on the upswing.
What New World Yacht Builders Said
On May 29, New World Yacht Builders issued a statement, which was sent to all marine magazine media. The highlights of that statement are as follows.
Video And Photo Links
Original video footage of the launch mishap can be viewed at:
http://www.passagemaker.com/articles/web-extras/10-million-dollar-baden-capsizing-video/
Photos of Badën being towed while being supported in upright position by crane:
Video of a sail training ship being side launched down ship’s ways shows how a vessel with a high range of positive behaves after being laid on her beam ends:
https://www.youtube.com/watch?feature=player_embedded&v=P5dmOZW2QZI
