The United States Coast Guard (USCG) ‘Sentinel-class Fast Response Cutter’ Bernard C. Webber, was commissioned recently in the Port of Miami, the first in a new class of cutters from the Louisiana-based Bollinger Shipyards. Part of the USCG’s Deepwater programme, the Webber will based in Miami to conduct migrant and contraband interdiction missions throughout the Caribbean Sea and Gulf of Mexico; the Coastguard chose a tried and tusty propulsiion system and a well-proven ship design fot these new patrol boats.Sentinel-class Propulsion System
The Sentinel Class is powered by two 20-cylinder MTU marine diesel engines with a patrol boat or light duty rating well in excess of 4,300 kW at 2,100 rpm driving twin propellors through ZF Marine 23560C transmissions. A bow thrust gives 75 kW power for manoeuvring.
ZF Marine 23560C Transmission Unit: Photo credit ZF Marine
Interestingly, ZF Marine has a long record of providing the USCG with propulsion machinery, and... [More]
Most fires on board ships start in the engine room. One of the built-in safety features increasingly found compromised by U.S. Coastguard Port State Control Officers are malfunctioning fuel Quick-Closing Valves (QCVs). Some QCV’s are espied deliberately blocked by a variety of means according to Marine Safety Alert 01-11 putting the vessel and its crew at greater risk in a fire emergency.
QRV Wedged Open: Photo credit US Coastguard
Perhaps an overzealous application of the recommendation by the USCG that routine checks of QCV systems be carried out led to the following incident reported in the October 2011 edition of MARS (the Nautical Institute’s voluntary and confidential ‘Mariners’ Alerting and Reporting Scheme’) which again focussed attention on the operation of QCV’s. Blackout, Propulsion & Steering Shutdown Follows QCV Test at SeaA loaded small-sized gas tanker nearing the end of a coastal voyage had on board a company superi... [More]
Results of an extensive atmospheric research project carried out in 2010 have now proved California’s clean-fuel regulations (applied within 24 miles of the coast since July 2009) have been effective in reducing Sulphur Dioxide air pollution from ships. In a recent press release, Chairman of California Air Resources Board, Mary D. Nichols declared this as good news for California, and for the nation. But there is a downside to that good news; the procedure of fuel-switching from heavy fuel (HFO) to low-sulfur distillate fuel oil (LSDFO) carries a risk of engine shutdown or malfunction, and the frequency of these incidents is on the increase.Spearheaded by scientists aboard NOAA research ship Atlantis the composition of emissions from more than 70 ships over 24 days was analysed during the ARB federal-state research project, and within that timeframe researchers also found that all ships were burning low-sulfur fuel. Assuredly, for economy, the majority had switched fu... [More]
America's oldest commissioned warship, USS Constitution, and indeed the oldest such combatant in any navy, still gets underway, as it did yesterday to salute the U.S. Navy's victory at Midway Island during World War II with 200 Gold Star families aboard as guests. Although the ship does not operate without tug assistance, it does get underway, and on occasion will unfurl sails. Her Sailors must learn their sailing skills aboard the U.S. Coast Guard's training bark USCGC Eagle, home ported about two hours away at New London, Ct.Seeing the ship underway serves to remind us of a day when canvas and wind were the means of propulsion for virtually all ships, in trade or armed for war.Constitution’s crew today is very much a team of contemporary surface warriors in a high-tech Navy, but has the honor of perpetuating naval customs and traditions, not to mention technology. This is evident not only from her sails, but from her gig crew's participation in a recent boat r... [More]
Polar Star: USCG photograph
USCG icebreaker Polar Star, one of the world’s most powerful non-nuclear fuelled, will continue in service with well-proven Thordon (of Canada) seawater lubricated propellor shafts by the time she returns to service in December 2012 after a USD 62-million refit and upgrade program in the Todd Pacific Shipyard in Seattle. Why a seawater lubrication system when most ships rely on a conventional oil lubrication system to protect stern-tube bearings?Icebreaking Stresses the Propellor ShaftForging a passage through polar pack-ice of necessity causes the propellor to impact with chunks of ice that cause bending moments in the propellor shaft, which in turn stress the stern tube bearings and shaft seals; when the outboard stern tube seal fails, lubricating oil leaks out to pollute pristine polar waters. (So-called ‘biodegradable lube-oil’ fails to deliver its promise in such sun-starved high-latttitudes and toxic substances in the lubrica... [More]