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ddiplock
10-14-07, 09:31 AM
I've tried searching the forums for tips on how to properly use it, but i'm not quite sure i fully know how to use it correctly. I've just taken a 3 minute reading of a Japanese Merchant, and its done 0.4 miles in 3 minutes, so, how exactly do I use the nomograph to measure the speed??

I know its a case of drawing a line through the graph, but I think i'm doing it wrong.

Any help guys? :)

cheers

ddiplock
10-14-07, 12:22 PM
Anyone? Please?? :)

Rockin Robbins
10-14-07, 01:17 PM
The nomograph! Fun and games for sure. I don't have a screenie to demonstrate with so we'll wing it with words. Your nomograph has 3 lines, time, speed and distance. Using it, knowing any two will let you figure out the third. In your example, your ship went .4 miles in 3 minutes. Take your ruler line drawing tool and draw a line from .4 miles on the distance scale, connected with 3 minutes on the time scale. Extend the line if you have to so it crosses the third scale. Where it crosses on that will tell you the ship is going 8 knots. Good enough or should I cook up a screenshot?

mrbeast
10-14-07, 01:19 PM
No Problem ddiplock.:up:

So you have timed a ship and in 3 minutes it has travelled 0.4 nautical miles. To find the speed:

1. Simply draw a line, anchoring it on the 3 minute mark on the time scale.

2. Extend it so that it crosses through the 0.4 miles mark on the distance scale.

3. Finally extend the line so that it crosses the speed line, where that line crosses should indicate the calculated speed.

It might not give a round figure, for example, if the line crossed roughly half way between say 5 and 6 knots then put in down as 5.5 knots etc something like that.

ddiplock
10-14-07, 01:58 PM
The nomograph! Fun and games for sure. I don't have a screenie to demonstrate with so we'll wing it with words. Your nomograph has 3 lines, time, speed and distance. Using it, knowing any two will let you figure out the third. In your example, your ship went .4 miles in 3 minutes. Take your ruler line drawing tool and draw a line from .4 miles on the distance scale, connected with 3 minutes on the time scale. Extend the line if you have to so it crosses the third scale. Where it crosses on that will tell you the ship is going 8 knots. Good enough or should I cook up a screenshot?

No that's fine thanks, it just so happens that I got 8 knots when i used the nomograph too, so i'm guessing I was using it the right way :) its just 8 knots seemd a bit fast to me for a freighter :S lol :)