Boat Design Forums  |  Boat Design Directory  |  Boat Design Gallery  |  Boat Design Book Store  |  Thanks to Our Site Sponsors
  #1  
Old 01-08-2017, 10:07 AM
stlamont stlamont is offline
 
Join Date: Jan 2017
Rep: 10 Posts: 1
Location: Kingston Jamaica
can someone please help

1. Need urgent help in how to calculate total cargo weight a ship carry.

2. A ship is expected to sail a distance of 3,200 n.m. at an average speed of 12

knots. Calculate her expected time of arrival if she departed on December 28,

2014 at 2200 hours.
Reply With Quote
  #2  
Old 01-08-2017, 12:03 PM
Olav's Avatar
Olav Olav is offline
arch. nav.
 
Join Date: Dec 2003
Rep: 460 Posts: 277
Location: Filia pulchra Lubecę
1:

Payload = Total displacement - light ship weight - provisions (fuel, lube oil, food,...) - ballast water

2:

Distance travelled: 3200 nm
Avg. speed: 12 kts = 12 nm/h

--> Time en route: 3200 nm/(12 kts * 24 h) = 11.11111 d.

Since 2014 was no leap year, the time of arrival is on

March 11th, 2014 (Feb 28th + 11 d), at 0.11111 d - 2 h (remaining two hours from Feb. 28th), thus at 0:40 in the morning (assuming the vessel stays within one time zone).

Was this your homework, stlamont?
__________________
All the best, Olav GER-1045 ____/)_/)/)___
Reply With Quote
  #3  
Old 01-08-2017, 03:55 PM
Heimfried's Avatar
Heimfried Heimfried is offline
Senior Member
 
Join Date: Apr 2015
Rep: 37 Posts: 154
Location: Berlin, Germany
Quote:
Originally Posted by stlamont View Post
[...] she departed on December 28, 2014 at 2200 hours.
Quote:
Originally Posted by Olav View Post
[...] the time of arrival is on March 11th, 2014 [...]

Was this your homework, stlamont?
No, no, the homework is: doublecheck the results of your friendly helper.
__________________
Gruss, Guenter
Reply With Quote
  #4  
Old 01-08-2017, 04:59 PM
Olav's Avatar
Olav Olav is offline
arch. nav.
 
Join Date: Dec 2003
Rep: 460 Posts: 277
Location: Filia pulchra Lubecę
Oops!

Correction: January 8th, 2015 at 0040.

Don't know why I read February instead of December...
__________________
All the best, Olav GER-1045 ____/)_/)/)___
Reply With Quote
  #5  
Old 01-08-2017, 07:31 PM
Mr Efficiency Mr Efficiency is online now
Senior Member
 
Join Date: Oct 2010
Rep: 677 Posts: 5,246
Location: Australia
Question 1 looks tricky to me !
Reply With Quote


  #6  
Old 01-08-2017, 08:24 PM
kilocharlie2 kilocharlie2 is offline
Junior Member
 
Join Date: Nov 2016
Rep: 20 Posts: 22
Location: Left Coast, North America
Compliments to Olav, who makes the answers seem simple!

Question 1 involves a technique known to mathematicians as subtraction. Question 2 involves a method known as division.

Of course it leaves out choice of route, time of year, winds, current, coriolis effect, and error.

On the ocean, we do not plow through distance, we plow through moving water and wind. It's a blasted good ship design that makes 12 knot in all weather and current, and a phenomenal skipper who stays on course around 1/8th of the planet, although our GPS / computer combo is making solid inroads into this last part.
__________________
Measure twice, cut once. It prevents "Damnit! I've cut it 3 times and it's still too short."
Reply With Quote
Reply



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.

All times are GMT -5. The time now is 03:32 AM.


Powered by: vBulletin Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Web Site Design and Content Copyright ©1999 - 2017 Boat Design Net