Your last paragraph ["From The Bridge" Tuggers Spring Issue No. 63 - ed.] in discussing the placement of ballast causes me concern. In it you say, "Using engineering principles, Jim wanted to make his boat's motion more comfortable. Using time-tested manufacturing practices, Tommy wanted to make his boat safer." From that it could be inferred that I put comfort above safety. Nothing could be further from the truth.
Placing the ballast on centerline when the design is a powerboat does nothing for the design other than add weight. With the ballast on the centerline it as no value as a roll deterrent. Simple proof of that is that Robert Beebe and Steve Dashew both use "flopper-stoppers" to combat roll and both place the weights (ballast) outboard and at a location about 65 -70% aft where the maximum waterline beam is usually located. Sailboats place the ballast on centerline to offset the load forces on the mast. If the ballast was split on a monohull it would have less force to compensate the pressures on the sail.
I divided the ballast between port and starboard and placed equal amounts high up to maximize the moment arm and thereby maximize the foot pound forces in countering any waves wanting to make the boat roll. This is similar to adding bilge keels but much better looking.
I think to have people believe that I set the ballast outboard for comfort reasons at the cost of safety (implied) is completely inaccurate. The fact that the boat was designed to SNAME and ABYC standards indicates that the design had safety as first consideration during the entire building process. For that very reason a weight study to determine the longitudinal, transverse and vertical center of gravities, taking nearly a week to develop, was used to insure proper location of the centers of each. I still stand by the design and the method used to control the roll based on knowledge available in 1982. Unfortunately, if the ballast is indeed on centerline it may be difficult to realize the difference it would have made to build the design to the plans.
[From an email dated 10 May 2015]
Before people start wondering why the boat(s) was built differently than the plans require, understand that the role of the yacht designer is not to inspect the progress of the design; that can be done but is separate of the design fee and contract. Loren was the importer and was also the inspector of record (self appointed) and he decided what would be acceptable regarding changes. My design firm was unaware of most of the changes made. Loren did not provide information on changes he made or approved, although the design contract required such to occur.
As designer, I adhered to the standards of that time going so far as to hold conversations with SNAME (Society of Naval Architects and Marine Engineers) regarding the designing of the freeing ports due to boat size and calculated freeing port size. If anything, the design is over built as designed (emphasis on designed). Since the first tug was launched I am unaware of any accident caused by improper design that resulted in injury or loss of life.
What owners need to remember is the design was done in 1982, before hull fairing programs, before righting moment and laminate calculation computer programs. Weight studies were done by hand, took over forty hours to do and were done using HP's 41C hand held calculators. No one had 3D CAD and what computers we could afford were floppy disk driven with memories too small to run engineering programs.
One thing that designers were full aware of was safety. Designing boats required that a designer accept the moral responsibility that people would use his design and therefore those peoples' lives were dependent on the designer working to a standard that most people would not be required to achieve. We worked in three axis, horizontal, longitudinal and vertical center of gravities, and to standards as thick as two typical books and were subject to inspections by the US Coast Guard.
The easy part was making the design look like a tug.
[From an email dated 18 May 2015]