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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Barrels was DR thread from Nov-Dec '04
From: Bill B
Date: 2005 Jan 28, 17:37 -0500
From: Bill B
Date: 2005 Jan 28, 17:37 -0500
Doug George posted a plausible explanation of the cube method, but I have not seen your posting on how a merchant marine would solve the problem. Any hope I will see another way to skin the cat from you? Bill > As for Bill's question about turns and fuel consumption the easiest way for > me to show how much fuel these larger,laden vessels consume would be to take > a question out of the C.G. exam for 3rd mate,unlimited as an example. > > Q: The speed necessary for reaching a point at the designated time is 18.0 > kt.The pitch of the prop is 23.9 ft.How many rpm will the shaft have to turn > with a - 2 % slip to reach the point in the given time? > My calculated rpm = 77 rpm > > If the fuel consumption at the above shaft rpm is 215 barrels/day what will > be the fuel consumption if the vessel's speed is reduced to 14.0 kt.? > My calculated consumption = 102.3 BBLS/day > The correct answer = 101 BBLS/day > > Close enough to pick the correct answer out of the supplied answers but my > calculated rpm is apperantly high as shown by the 102.3 barrels instead of > 101 barrels.So,in real life, you can see that a fair amount of money would > be lost if calculated incorrectly.