07/24/2009, Providence
AIS Chartview Showing Name, Course, Speed of Commercial Traffic
A chance encounter with the cruise ship Jubliee as we were sailing north from Newport in the East Passage recently got us again thinking about AIS (Automatic Identification System). We were sailing north "wing on wing" approaching Red 26 near Mount Hope Bay. We could see a southbound cruise ship bearing down on us, but could not determine it's intentions. We were both constrained by R26 and had limited maneauverability, and it appeared that a risk of collision existed.
Wing-on-Wing With M/V Jubliee Dead Ahead
We hailed the other vessel on the bridge -to-bridge channel 13. "Southbound Cruise vessel approaching R26 this is the sailing vessel CEILI approaching off your starboard bow."We could not make out the name of the vessel, or its precise course or speed. Fortunately, the other captain was paying attention, and quickly responded. He indicated that we could take him starboard to starboard, and we were able to pass close without incident and without a sudden jibe, which would have been our only other option.
Had we been equipped with AIS, we would have been able to hail the vessel by name, or call the vessel directly using it's MMSI identifier. Most commercial vessels are required to transmit AIS signals, which include at least the vessel's name, present position, course, speed, and other information. If we were also transmitting on AIS, the cruise ship would have the same information about us. In fog, or reduced visibility, the advantages are multiplied. In this circumstance, an unknown radar target can be quickly identified as a large commercial ship early enough to avoid a close encounter.
Class A transponders have been required on most commercial vessels since 2003 and transmit on VHF frequencies at a power of 12.5 watts, with a practical range of 20-30 miles. Class B transponders have just recently been approved for small commercial and recreational boats, transmit at 2 watts power, and have an effective range of 5-10 miles.
New generation chartplotters from manufacturers such as Furuno and Raymarine can accept AIS signals (with the appropriate hardware) and overlay AIS information on the chart. Older generation chartplotters, such as the Raymarine RL series on Ceili, cannot process AIS information in this way. Because of this, the AIS options for those with older generation chartplotters are more limited. One solution is a stand alone AIS receiver paired with an onboard computer (generally placed at the nav station).
Example of Computer/AIS System (Fugawi)
Another solution is a stand alone AIS transponder with it's own screen, suitable for helm mounting.
One such stand alone unit is manufactured by Simrad, the AI50. This unit features a color screen, and is small enough to be unobtrusive at the helm. No doubt, other maufacturers are racing to bring similar units to market.
Simrad AI50 stand-alone Class B AIS transponder
For a real-time example of AIS, check out MarineTraffic/AIS in the Links.
The transmission of AIS signals by recreational vessels has generated some controversy, especially among commercial operators. A recent article in Soundings August 2009 issue titled "AIS Could Save Your Life" discusses some of these concerns.
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07/19/2009, Newport
Coronet
On Sunday morning, we explored the restoration shed at IYRS (International Yacht and Restoration School) where the Coronet is undergoing restoration.
This grand sailing vessel was built in 1885, and featured an oppulent interior complete with a grand piano. It won the Transatlantic Race in 1887 in a little over 14 days.
The ship went through a series of owners, and was involved in world and scientific exploration, as well as missionary work until it was acquired by IYRS in 1995.
The restoration project has proceeded slowly, and in 2006 ownership of the project was transferred to Coronet Restoration Partners, with work planned to continue at the IYRS Newport location.
Coronet Under Full Sail
Coronet is a 131 foot Gaff-Rigged Schooner
Interior of Coronet prior to disassembly, showing intricate mahogany interior
Removal of bow hull planking reveals extensive deterioration of structural ribs
Stern of Coronet Showing Last Hailing Port (Portland, Maine)
At the time of her construction, internal combusition engines did not exist. She was eventually fitted with twin engines. Port side prop and shaft are shown.
Deck Dorades Removed and Stored in Restoration Shed
Wooden Sailing Blocks
All interior furniture and fittings have been removed, cataloged, and await restoration
Shop on site makes restoration parts; shown here are ribs under construction
For more information, see Coronet/IYRS in the Links
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07/19/2009, Newport
Nose Art on Sleighride
On a dinghy tour of Newport Harbor, we spotted this interesting nose art.
Sleighride is a Goetz-built racer/cruiser. She was designed for speed by Sparkman and Stevens. This 77 foot carbon-fiber boat has cruised at speeds over 24 knots.
See Sleighride in the Links for more information
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