Rik van Hemmen's blog

When I wrote the blog on SWATHs I decided to see if I could locate my Virginia Tech research partner, Mark Tesh. With LinkedIn this was not all that difficult. He enjoyed hearing about the Monoform all these years ago, and remembered having taken photos back in 1981.

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Rik van Hemmen's picture
Thursday, February 11th, 2016

SWATH, the Art of Compromise

M&O has worked on both the implementation and the failure analysis on quite a number of SWATH (Small Waterplane Area Twin Hull) projects in the last decades. SWATH vessels hold great promise and continue to intrigue naval architects and potential ship purchasers. When we first became involved in SWATHs, as far back as 1981 with the Monoform concept, SWATHs were described as: “The best solution for small ships in big waves”.

 

That truism has not changed, but it is clear that not all small ships in big waves are SWATHs today, and so how can that statement be true?

 

The truth of the statement is related to the disconnect between physics and design. Anything can be most efficient for any one condition, but that does not mean that it will be most efficient once it is turned into a real life object.  

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I am almost certain that I learned more from popular culture than the classics (whatever the classics may be).

 

For example, the TV series M*A*S*H provided me with two philosophical bits that I still recycle on a regular basis. The first warns me to never drink when I need a drink, and the other restricts the need for tattoos by noting that it makes no sense to permanently inscribe something on your body if the art is not worthy of hanging on your wall.

 

These two bits came up during separate M*A*S*H episodes that I had only seen once many years ago when they originally aired. I had a very distinct memory of the scenes, but when I recently replayed the episodes on the internet, I found that the actual scenes were different from my memory.

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My list of big maritime things for the year may not look much like maritime at first, but, believe me, it is. To begin with, spaceflight’s closest real life cousin is nuclear submarine operations. Next, maritime is synonymous with international cooperation and, last, all technologies interbreed, whether up or down. Nothing is more difficult to design than a good space toilet, or a good small craft head and it takes dedicated individuals to make it happen.  

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Rik van Hemmen's picture
Monday, December 21st, 2015

The Search for Oil Spill Data

The September 2014 issue of the US Navy Institute Proceedings had a one page article named “The Biggest Oil-Spill Culprit? Mother Nature”.

 

This article indicates that the sources of oil pollution in the ocean can be divided as follows:

 

Air pollution 4.2%

Run off 11%

Transportation Accidental Spills 9.8% (Marine)

Transportation normal operation 24.1% (Marine )

Natural Oil Seeps 47.3%

Extraction of Petroleum 2.9%

Jettisoned Fuel 0.6%

 

The article has a nice looking graphic and it provided me a chance to ponder this data.

 

In looking at this, most oil pollution occurs on the ocean. Air and land initiated pollution accounts for only 16%. This seems low to me. Mostly because non-point pollution is so difficult to capture and the world’s coastlines are very, very, long with the majority of the world’s population living near the coasts.

 

That made me wonder as to where this data came from, and I called in our present intern Jose Ramirez. It would be a perfect high school intern job to perform a little detective work on this graphic.

 

Jose performed a tremendous amount of sleuthing in trying to establish the source of the data and this information is provided below.

 

Since the story is long, I will provide the conclusion first:

 

There is no reliable quantitative data on ocean pollution, even in order of magnitude estimates, and don't believe any estimates unless you have been provided solid data

 

The above graphics represents a mishmash of data that is no more recent than the year 2001 and actually is an average of data going back as far as the 1970's. As such, it is disturbing that there is a 2015 article that references a graphic based on a 2003 report that is no better than orders of magnitude correct. So who is at fault here? The scientists attempting to make an estimate of oil polution in 2003? The fact that there is no more accurate more recent information? Or that authors recklessly cite inaccurate 2003 research results in a 2015 article on a subject that is in rapid flux.

 

Bottom line:

 

With regard to quantifying oil pollution in the oceans we are groping in the dark.

 

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Over the years I try to write a blog around Christmas time that deals with the spirit of Christmas.

 

I have posted poems, art and stories, but this year a pass-it-forward present was dropped right into my lap.

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In a prior blog I commented on ignorance and how easy it is to jump to incorrect solutions. In that blog I made reference to Boyan Slat and his Ted Lecture as an example of an incredibly awful Ted lecture.

 

In his lecture Boyan Slat proposes a method for removing plastic trash from oceans. The lecture is presented by an enthusiastic young man in front of a basically ignorant audience. With universal approval he makes a moving appeal for doing something we all want to do: Save our environment.

 

A friend sent me link to this lecture knowing that I am one of those seaweed hugging engineers and hoping that I would enjoy this young man’s resolve. Instead I was horrified.

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Causal analysis is a surprisingly complex process that over the years has been subject to push and pulls from a wide variety of professional influences. When determining the actual cause of an accident or an incident, any number of stake holders would like to address the issue that “caused” the accident, whether to prevent a reoccurrence or, on the other side of the remedial spectrum, to punish the causal party.

 

In theory, there must be a cause for everything, but, in practice, finding the cause often involves a high level of judgment, and judgment is complicated and often deeply flawed. If judgment were to reside in one professional community, there is a possibility that some type of convergence on the determination of the cause of an incident could be developed. And once the cause is established, we can give that cause a name. It apparently is too simple to simply call it “the cause” of an incident, and that makes sense, since all too often there are multiple causes of an incident.  And because there can be multiple causes, different terms for causes have started to emerge.

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A recent Wall Street Journal article named The Myth of Basic Science by Matt Ridley makes a fascinating argument that government spending on basic science does not result in technical innovation. The article argues that, instead, most innovation results from tinkering, and only after the tinkering results in new technology, will science catch up to fully explain it.

 

It uses steam as an example where it notes that the science of thermodynamics did not mature until after basic steam engines were invented and operating. In other words, the article argues that science simply fills in the knowledge gaps of innovative ventures.

 

It then goes on to argue that therefore government sponsored basic science is a not an effective investment.

 

As often is the case, Wall Street Journal and its writers raise an interesting point but jump to conclusions rather than fully working through the problem.

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As noted in an earlier blog, we love loadouts, they are a uniquely satisfying engineering exercise and often bring out the best in all participants.

 

Loadouts are complex projects that need to be designed and guided by experienced personnel, but even the highest level of experience cannot always prevent a mishap.

 

For a number of years we have been involved in the resolution of such a mishap and our involvement resulted in the discovery of a potential loadout failure mode that needs to be further disseminated in the industry to prevent a reoccurrence.

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