Boat Design

New designs from our drawing board, and assorted thoughts on boat design in general.

Risk mitigation philosophies from the radiation world

Quite a few issues of safety, in the yachting world, come down to the preferences of the skipper and crew. There will never be universal agreement on how (or if) to use tethers, or on where a life raft should be kept, or on whether an extra EPIRB is a better investment than an AIS-B transponder upgrade.

We can, however, apply some general principles of risk analysis and risk mitigation at the design stage. The maritime world already has some ways of figuring this out, but for today, I think I'll shake things up a bit with some principles from a different field: ionizing radiation.

Starwind 860 design logic

"Why that?"

It has to be among the most common questions I get about the Starwind 860 trimaran. Why a tri-hull? Why that size? Why is it a powerboat?

Here's the short version of the design logic.

Dynamic Stability of a Monohull in a Beam Sea

The last post in our series on yacht stability looked at the static case. We saw that a yacht's response to heeling forces can be described by a stability curve, the shape of which tells us a lot about the boat's purpose, sailing characteristics and seaworthiness.

A real yacht in a real situation is of course far from being a static case. The static stability curve is one of our best tools for quantitatively comparing different designs, and I don't mean to denigrate its importance. In practice, though, dynamic factors can often have a bigger effect on the actual stability of the boat as it relates to safety, seaworthiness and comfort.

Engine technology to watch for

With the recent release of the final report of Nigel Calder's HyMAR project, marine internal combustion / electric hybrid powertrains are making waves once again- and not necessarily in a good way, as Calder's team found that the benefits of the expensive hybrids were limited to a relatively narrow, low-speed operating regime. We've known for quite a while that the major advantages of gas/electric and diesel/electric hybrid cars- namely, instant start/stop and regenerative braking- don't apply to boats. We've also known for quite a while that hybrid systems only make economic sense aboard ship if the house loads are comparable to, or larger than, the power required for main propulsion.

Tech addicts need not fear, though: There are many other fuel-saving and pollution-reducing technologies waiting in the wings, and hybrids aren't quite out of the running yet.