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Minutes

August 6, 2009 Minutes

DATE / TIME:        August 6, 2009, 1:00 p.m.

LOCATION:        DOT Headquarters
            1200 New Jersey Ave, SE, Conf. Rm. #2
            Washington, DC    

ATTENDEES:        Rich Sonnenschein (MARAD), Ch.
            Chris Bassler (NSWCCD)
            Bill Cleary
            Bruce Johnson
            Tapan Mazumdar (NAVSEA)
            Bill Peters (USCG)
                                    
    by telecom:    Chris Barry (USCG ELC)
            Geof Fuller (NSWCCD)
            Jane Louie (Gibbs & Cox)

Old Business:

1.    Introductions – Rich Sonnenschein welcomed the members in attendance, and those participating via telecom.  Dr. Bruce Nerling contacted Rich Sonnenschein, to inform the Panel of his retirement from the Naval Academy and formal resignation from Panel SD-3; the Panel wishes Bruce Nerling all the best in his retirement.  Rich Sonnenschein was also informed that LCDR Jason Smith has taken a new position locally with the Coast Guard, and been replaced on the Stability Panel with LT Sean Peterson.  There were no corrections to the minutes from the Panel’s previous meeting, held on May 28, 2009.  

2.    SLF-52 Developments – Bill Peters reviewed major SOLAS and SLF plans and activities:
SOLAS – Next SLF meeting is set for January 2010.  The new subdivision and damage rules entered into force on January 1, 2009.  An intersessional correspondence group is investigating whether there are any “gaps”, concerning RO/PAX ships with large, open holds.
New Generation Intact Stability Criteria – The intersessional correspondence group has submitted Part 2, addressing four ship vulnerability criteria, based on stability failure modes.  The next phase, concerning procedures for direct assessment (model test), is scheduled to be completed by mid-October 2009.
Guidance for the Safety of Fishing Vessels <12 m in Length, and Undecked at any Length – These voluntary standards are expected to be approved in 2010.
Adoption of 1993 Torremolinos Protocol – In efforts to help advance this protocol, questionnaires have been sent to nations with substantial fleets of fishing vessels greater than 24 m in length.
Passenger Ships – Ongoing issues include time-dependent survival (“time to flood”), return-to-port criteria, and the need for guidelines on watertight doors normally left open.
Tonnage Convention Update – Amendments to the 1969 tonnage rules are needed in order to apply the tonnage rules in a uniform manner to ship types which were rare or non-existent when the Convention was adopted.
Subdivision for General Cargo Ships – This new set of criteria applies to some ships, not covered by the 2009 probabilistic damage rules.

3.    Dynamic Stability Task Group (DSTG) – DSTG coordinator Chris Bassler discussed recent and future planned DSTG activities:  
•    The group’s seventh meeting took place on the morning of August 6, 2009.
•    The DSTG will lead a T&R Session and Presentation during the SNAME Annual Meeting in October 2009; the group’s efforts are being spearheaded by nine technical teams.
•    Next two DSTG meeting are scheduled for the morning of September 3 [later rescheduled], at NSWCCD, in Bethesda, and at the SNAME Annual Meeting on the afternoon of Wednesday, October 21.

4.    Stab 10 Conference Highlights – Chris Bassler discussed the June 2009 STAB 10 Conference in St. Petersburg, Russia, which he attended in June.  Impressively, out of a total of 85 papers presented, DSTG members were involved in 20.  STAB, an international standing committee, has workshops scheduled for 2010 at Marin and 2011 at NSWCCD, and in 2012, a conference in Athens, Greece.

5.    Review of Stability-Related PNA Draft Chapters –
•    Chapters 1 (Ship Geometry) and 2 (Intact Stability) have gone to publication and are available on the SNAME web.
•    Rob Tagg is revising the appendix to Chapter 3 (Damage Stability) per the new SOLAS rules; US Navy damage stability criteria, furnished by Tapan Mazumdar, et al, will also be incorporated.  Hopes are for a final draft by September 2009, and publication by the end of 2009.  Action:  Tapan Mazumdar will forward a copy of the approved Navy Damage Stability Criteria portion to Rob Tagg.  Chapter 3 will be published alone.

6.    Panel O-49, Small Working Vessels Operations & Safety Activities –
•    [Nothing to report]

7.    Panel SD-3 and SNAME Web Page developments -
•    Jane Louie discussed the ongoing progress with SNAME’s new web site.  Initially, this will include “group” sites - for committee discussions - and “micro” sites – to handle files of committee interest.  More files have been added to the Stability Panel’s microsite, which can be accessed at

   http://www.sname.org/SNAME/SD3Stability/Home/Default.aspx.

8.      Proposed Stability Guidance for Small Craft Designers -
•    Chris Barry prepared a brief write-up (see attachment, below) on the background and purpose of the proposed stability guide, which could increase SNAME’s presence in the small craft community.  
•    A major source for the evaluation of small craft stability, ISO 12217, presents copyright issues to overcome.  New Australian rules for small craft stability are also to be considered.
•    Spreadsheets for the stability analysis of small craft can be combined for an effective training module, but their development entails complications – particularly, in making the hydrostatic adjustments to account for trim – which are more easily handled by computer software.  
•    The high cost of user-friendly software, however, is a deterrent to its potential use by small craft designers, who generally have very limited training in ship stability, and limited resources for the purchase of ship modeling and stability software at the going price.  
•    It was suggested that vendors such as Rhino and others be contacted, to explore possibly ways to reduce the software price, for training purposes. One other concern: how much training of small craft designers is required, in order to assure that they use the software properly?

New Business:

•    The capsize of the RO/RO vessel, FINNBIRCH, due in part to a failed cargo securing system, was briefly discussed.  Bruce Johnson suggested this incident as another example of “impaired stability”.

Action Items:


•    Dynamic Stability Task Group – A T&R presentation and meeting are scheduled during the SNAME Annual Meeting.
•    Tapan Mazumdar will forward the approved US Navy ship damage stability criteria to Rob Tagg, for inclusion in PNA, Chapter 3 (Damage Stability).
•    Jane Louie will continue adding materials to the Stability Panel web page as needed, and keep the Panel members apprised of major developments.
•    Chris Barry and anyone assisting his efforts are encouraged to contact multiple vessel modeling and stability analysis software vendors in conjunction with the proposed project development for Guidance for Small Craft Designers.

Adjournment / Next Meeting - The meeting was adjourned at 3:15 pm; the next Stability Panel meeting is scheduled for 9:30 – noon on Wednesday, November 4, 2009, at the DOT Building.

ATTACHMENT

Project Proposal:  Stability Guidance for Small Craft Designers (Chris Barry)

1) Background:

Until relatively recently, there were only very limited criteria for the stability of craft under 65 feet, especially recreational boats.  The requirements applicable to small craft were:

46 CFR 178-179 (small passenger vessels under 65 feet/100 gross tons/150 passengers): Must pass a "simplified stability test" comprising moving a weight producing a moment equivalent to either a specified shift of passenger weight to one side, or a specified wind force.  Under this moment, there is a minimum required residual freeboard on the low side.

33 CFR 183 (most motor recreational boats under 20 feet): Passenger and weight capacity (posted on a mandatory label) is determined by the ability to pass tests comprising a fraction of the deadweight when evenly loaded such that the freeboard to downflood is zero, by a passenger weight shift such that the freeboard to downflood on one side is zero, and the maximum weight that can be floated in the flooded condition (by fixed foam flotation), including a shift of weight to one side.  No standards are required of craft over 20 feet.

2) Recent Changes

More recently, however, ISO 12217 has been accepted for compliance to the Recreational Craft Directive (RCD) of the European Union. This has a fairly complex set of criteria based on the exposure of the craft and similar issues.  The exposure criteria range from Category D (sheltered waters) to Category A (long open ocean voyages).  Category A and B include "Terremolinos" type righting energy area criteria and "severe wind and wave" energy criteria, both of which involve detailed calculation of righting arms and are explicitly required to correctly assess trim on the righting arm, etc.  These standards also have fairly complicated additional standards for sailing craft.

There is also growing interest in the quasi-military/police small craft market, which increasingly imposes some stability criteria as part of their procurement requirements.  However, many of the builders of these craft are not experienced naval architects, either.

3) Need

As a result of this change, and based on increasing availability of computers, CAD software, and so on, (and with recent stability related accidents in small passenger craft), small craft designers are becoming increasingly interested in stability assessments beyond just single waterline hydrostatics.  Unfortunately, many small craft designers have limited education in naval architecture, having either "learned by doing" without formal training or having taken mail order courses or other limited training (see, for example www.westlawn.edu and http://www.macnaughtongroup.com/school.htm).  

This means that here is an opportunity to provide training and/or material on stability issues focused on small craft designers, independent students of small craft design and others in the recreational boat industry.  However, doing so practically requires more than just explaining the concepts, rather, there should be some means for a designer to actually perform at least intact stability analyses, which in turn implies the availability of basic software that could do upright hydrostatics and righting arm curves free to trim.  These capabilities are included as part of a number of other packages that are primarily hull surface definition packages, but these latter may not be accessible to all students, (since they are quite expensive) and SNAME should not be in the position of endorsing just one.

There is a project in the small craft committee to develop a bulletin on small craft stability, but it would be nice if there were also a training module that included exercise problems and a minimal software package.

It may be worth figuring out if there was some way SNAME could help make something like this available, especially because this would help SNAME improve its presence in the small craft community.