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January 2011 www.sname.org/sname/mt interpreting ice pressures measured dur- ing ramming tests r 4 I J Q J D F G S J D U J P O G B D U P S 5 I J T Q B S B N F U F S aects ship resistance. It has been mea- sured during some detailed ship resistance test programs, such as those intended to evaluate the performance of a low-friction coating over time on an icebreaker r ( F O F S B M J D F D P O E J U J P O T 5 I J T J T C B T J D information that is useful for practi- cally all ship trials in ice. Often, video cameras are installed on the ship (for example, on the mast and/or on the sides of the ship) to document the ice conditions seen? by the ship. Photos taken from supporting helicopters are very valuable, and this is an integral part of nearly all ship trials in ice. Looking ahead Ship trials in ice have played a key role in the development of the improved designs that are todays icebreaking ships. As naval architects continue to produce improved designs, pro- gram-specic eld testing will be required to evaluate them, and the large body of knowl- edge that has been gained from eld work done to date will serve us well in planning and executing ecient programs targeted to provide the required information. It is worth noting that, in contrast to open-water testing for ships, detailed test manuals for ship trials in ice are not gen- F S B M M Z B W B J M B C M F ? B M U I P V H I F G G P S U T I B W F been made towards this goal. See Further Reading? for details on this work. With the multitude of factors that need to be consid- ered in planning an ice trials program in ice, the development of a SNAME T&R bul- letin focused on ship trials in ice could be a useful step forward. George Comfort is the leader of BMT Fleet Technology Ltd.s Cold Regions and Materials Technology Group. Andrew Kendrick is vice president, operations of BMT Fleet Technology Ltd. Claude Daley is director of the BMT Ocean and Arctic Structures Research Program. Peter Noble is a chief naval architect at ConocoPhillips. FURTHER READING | A report prepared by BMT Fleet Technology Ltd. in 1987, for the Government of Canada, oers more information on ship trials in ice. The report is entitled Canadian Coast Guard Fleet Manual, Post Acceptance Performance Assessment (PAPA) Manual , and its available from Ottawa: Director General , Fleet Systems, Canadian Coast Guard Headquarters. ABOVE: Ice core samples are taken for ice temperature and salinity measurements. RIGHT: A cantilever beam test is conducted to measure ice ?exural strength. BOTTOM RIGHT: Among other things, measuring the ice-hull friction factor of a vessel can help determine performance of low-friction coatings over time on an icebreaker.