January 2006
Table of Contents:

Southwest Section

Chesapeake Section

Greek Section

Northern California Section

Southwest Section
by George Sidney

September 20, 2005

The Southwest Section held a technical Section meeting on September 20, 2005 at Qwiggs. The first order of business was to inform attendees of current goals for the Section, which are: improving membership, presentation documentation, and diversification to attract the various segments of SNAME membership. In addition members were informed of plans to hold a Symposium in Las Vegas, Nevada in 2006.

The meeting continued with a presentation on "Use of Field Monitored Data for Improvement of Existing and Future Offshore Facilities" by Dr. Igor Prislin. The presentation gave us some insight on the various types of offshore facilities that exist in the Gulf Coast, and water depths in which some of these platforms work. All data pertaining currents and weather are analyzed to maintain these platforms in good working order. After the presentation was completed, Dr. Prislin was presented with a certificate of appreciation.

November 22, 2005

The Southwest Section met on November 22, 2005 at Fiddlers Green Restaurant. The first order of business was to inform attendees on the success of SNAME's annual meeting, which was held in October of 2005, and the steps being taken by Headquarters to improve membership dues receipts through the SNAME website.
In addition It was reported that the CCDOTT conference in Long Beach was a great success with significant attendance. Also, the final arrangements for the Las Vegas Symposium are underway, and will be held April 20- 22, 2005.

The meeting continued with a presentation on "Analysis, Fabrication, and Testing of a Composite Bladed Propeller For a Naval Academy Yard Patrol (YP) Craft " by Ensign Christopher Wozniak, United States Navy. Ensign Wozniak gave an excellent description and view of the process taken through the analysis, design and fabrication of a carbon fiber composite propeller, and the final test that took place by installing the propeller into the Naval Academy's Yard Patrol craft. The highlight of the night came when Ensign Wozniak described the cumbersome task of removing the existing propeller, which took hours to rig because of the propeller’s weight. However, re-installation of the composite propeller took only 15 minutes because two people could pick it up.

After completion of the presentation Ensign Wozniak was presented with a certificate of appreciation.

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Chesapeake Section
by Steven Milne

November 21, 2005

More on the not so simple “inclining test”

On Monday, November 21st, the SNAME Chesapeake Section held its second “full house” Section meeting at the Eastport Yacht Club. Over 50 members and guests who attended the meeting, participated in a lively discussion following the technical presentation given by John Womack of St. Michaels Ship Design.

The presentation was on a SNAME T&R funded project, designed to evaluate alternatives to the traditional inclining pendulum device and to provide guidance on selection and use. . It is difficult to rig long enough pendulums for small vessels, which typically have 14-16 foot GMs. The inclining experiment is also a larger part of a smaller vessel's budget, resulting in cost constraints and placing a premium on reliability and accuracy to avoid repeating an experiment. Alternatives to the classic pendulums with oil-filled trough dampers will be evaluated, including water tubes, digital levels with data logging and tilt/clinometer sensors. A "teeter-totter" test rig was devised, driven by a rotating castor wheel (or cam) to simulate low (up to 1.5 degree) and high (up to 3 degrees) angles of dynamic wind and wave influences. "Crew effects" on measurement accuracy will be evaluated using yard personnel under typical inclining experiment conditions, training and preparation. Investigation topics were static angles, motion effects and functional ability (i.e., ease and cost).

There are no known comprehensive statistical error studies for inclining experiments. The results are typically treated as absolute values. A companion (follow-on) T&R project was proposed that covers different vessel types, as different types will have different error statistics. Why is this new study necessary? For three reasons:
1) A measure of merit is needed to know if a is satisfactory;
2) If the test was not satisfactory, ways it can be salvaged; and
3) The Australian Transportation Council has prepared a new stability test standard that replaces the traditional tangent plot with a statistical analysis using standard deviation. There is a need to go further, to establish a confidence level for inclining experiment results.

The results of such a study will consist of guidelines for inclining experiment method selection and guidance on inclining experiment accuracy.

A written discussion was submitted by Chris Barry (chair of Small Craft Committee) that covered the following points:
1) Inclining experiments are analogous to celestial sites in terms of measurement accuracy
2) There is a need to upgrade the technology, as happened with celestial navigation.
3) There is only anecdotal evidence that more than two pendulums and alternative measurement techniques are improvements; he expressed appreciation to the investigators for the real progress the project team is making.

Comments following the presentation, covered practices at Newport News Shipyard, the challenges for small vessels, draft mark versus freeboard reading accuracy, and the role of inclining experiment in weight and VCG validation as well as stability. The project team (John and Bruce Johnson) provided responses to both written and verbal discussions. Verbal comments were made by Matthew Collette, Wenonah Hlavin, Jean Kazinsky, Bob vom Saal, Gene Haciski and Bill Peters.

In addition to the technical presentation, Jaideep Sirkar, Chairman of the SNAMET&R Steering Committee, provided an overview of the T&R Program. In Chesapeake these short, but informative presentations are the "warm-up act" for the technical program. He announced current T&R news, including greater SNAME/ASNE co-operation in T&R, and highlighted recent T&R work on the crashworthiness of ships, oily water separators, and the stability of small passenger vessels. Jaideep impressed the members with his proposals for student member involvement, and directed all to the website: www.sname.org/technical_committees.htm.

John summarized the numerous comments by describing the project team’s plans for 2006. They will submit another proposal to T&R (speaking directly to Jaideep we might add) to complete the project, which will include a paper for the November 2006 Chesapeake meeting at Eastport YC, and we anticipate this paper will appear in Marine Technology.

Just a final few words to express Chesapeake Sections appreciation to our host Eastport Yacht Club. Baltimore and Annapolis have been selected as host cities for the only U.S. stopover of the Volvo Ocean Race, 2005-2006. Their website has links to the Volvo Ocean race updates and the restart of the race, leg 7 is in April. The EYC website is at: http://www.eastportyc.org/

The Eastport Yacht Club sets a good buffet, but it does get pretty cozy with 50 in the meeting room; note the photos of yachts and sailboats around the walls.

December 6, 2005
by Pat Naughton

Constant Friendship – voyage to Maryland – 1670

On Tuesday December 6th, nearly 50 SNAME members and guests and 16 student members attended a Chesapeake Section presentation by Mr. John Wing describing the voyage of a 17th Century sailing vessel engaged in supply of Colonial settlements in the Chesapeake Bay area. The meeting was held at the Washington Navy Catering and Conference Center.

In his presentation Mr. Wing indicated that he had been able to reconstruct details of the three-masted sailing ship Constant Friendship, and one of her typical voyages to the New World, from a 19 page navigator’s log from that period which had been preserved in Oxford University in England. Mr. Wing noted the historical significance of this document; it contains more ship-information than other sources – of the fleets of sailing ships that supported early colonization of North America.

Based on the details in the log, and assistance from other naval historians, Mr. Wing had a model of the Constant Friendship commissioned to show how a typical vessel of that period would look.

As described in the navigator’s log, the Constant Friendship was fairly large for her time, with three masts, displacing an estimated 215 tons with a length on deck of about 85ft and a beam of about 26ft. Additionally, it was deduced that she had a “ship rig” (similar to that of the Mayflower) with no staysails or topgallants.

Mr. Wing noted that during the period between 1670-1700 voyages to the Chesapeake Bay region exceeded not only the number of voyages to the New England Colonies, but also those to the West Indies as well. The reason for this was the harvesting of tobacco, which was an important crop of that period. Mr. Wing noted that typically most of the vessels making voyages to the New World at this time were either two or three masted vessels, but if freight rates were high, even smaller single-masted vessels would sometimes brave the harsh Atlantic weather to make the voyage.

Based on the data recorded in the navigator’s log, upon leaving England the vessel sailed a SSE course to the known latitude of the Virginia Capes and then sailed due west. Upon arrival in the Chesapeake Bay region the vessel would spend at least 2 to 4 months discharging passengers, stores, and merchandise and then loading tobacco for the return trip to England. Eventually the ships would leave before warm weather set in (to avoid the threat to the crew of disease and damage to the vessel from ship worms). For the return journey, the ship would sail a more northerly route to take advantage of prevailing winds of the Gulf Stream. As described in his presentation, the voyage could typically be harsh, with the threat of disease, war and other hardships always present.

In all, the author was able to provide a fascinating insight into an interesting period of nautical history as well as the history of the U.S. and the Chesapeake Bay region. We are encouraging John to turn this outstanding historical presentation into a Marine Technology article, as the MT Committee is seeking varied articles for the journal.

The Chesapeake Section was pleased to welcome student members from Virginia Tech and the Naval Academy to a “student event” held before the evening technical meeting. This event was a direct result of the successful Student Summit held on at the SMTC & Expo 2005. Credit for initiating this event goes to the active chair of Virginia Tech student section Justin Stepanchick. This section was pleased to have President Compton introduce the afternoon’s program. Please follow the links to the student event agenda/timetable and President Compton’s report on the event in the January issue of eNewsLetter.

http://www.sname.org/sections/chesapeake/papers/students.html

http://www.sname.org/newsletter/news0106.htm

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Greek Section
by Nikos Dionissopoulos

December 8, 2005

The second technical meeting of the Greek Section for the season 2005-2006 was held on December 8th, 2005 in the presence of more than 90 members, non-members and students, during which Dr. Bjorn Johan Vartdal, Senior Engineer at the DNV Machinery and Propulsion Systems Department of the Maritime Technology and Production Center presented his paper on the topic ‘State of the Art Shaft Alignment ’.

Historically, shaft alignment has been treated using purel static analysis with fixed boundary conditions. The increase in the number of damages due to shaft misalignment, experienced in the 1990s, led DNV to look into the complexities of shaft alignment. Two effects that could affect the alignment of the shaft were selected for in depth analysis. These were static variation of boundary conditions due to hull deflections, and dynamic variations due to hydrodynamic loading on the propeller. Two major joint industry research projects were launched in order to investigate these effects. The ‘Flex’ project investigated the effects of draught variations and tank filling on the deflections of a flexible hull and its effect on the alignment of a stiff shaft and on the main engine. The ongoing ‘Flex 2’ project investigated the effects of the hydrodynamic loads generated by the propeller on the alignment of the shaft. The presentation highlighted the way that these projects have changed the way DNV looks at shaft alignment and indicated the main findings of the projects so far.

Interesting details were presented about the sophisticated instrumentation used, which included lasers and measurements made on board the new Kristen Navigation’s 320.000 t dwt tanker M/V Aquarius Voyager. These included shaft and bearing deflections, loads stresses, slopes etc… Design trends were also discussed and statistics were presented on the frequency of stern bearing damages since 1975.

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Northern California Section
by Tom Mader

December 14, 2005

Cal Maritime Propulsion Plant Simulators

On December 14, 2005 members of SNAME Northern California Section and ASNE Golden Gate Section gathered at the California Maritime Academy for tours of its Diesel and Steam Plant Simulators. Cal Maritime is a unique and specialized campus of The California State University. One of seven degree-granting maritime academies in the United States, Cal Maritime offers students a specialized education combining classroom instruction, experiential learning, and professional development in preparation for successful careers in the maritime industry. In addition to the operational and maintenance training students receive during summer cruises, the Diesel and Steam Plant Simulators on campus provide a comprehensive hands-on experience in the application marine propulsion plant technologies. In these full-mission simulators Cadets engineers gain an understanding of integrated plant operations, learn fault analysis techniques and develop their communication and management skills in routine operations and casualty scenarios. Operational demonstrations of the Diesel and Steam Plant Simulators provided attendees a close-up view of the cadet learning experience. Following the simulator tours members of the professional societies, and students from the University of California, Berkeley and California Maritime Academy who were in attendance, socialized and enjoyed dinner in the Academy Wardroom.

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