"Trinidad to Mid Atlantic ridge" chart limits

Roberto

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BA 4407 chart is named "Trinidad to Mid Atlantic Ridge": does it include the Açores islands (at least one of them) on the NE corner ?

I tried the BA catalogue but the image of the chart is so small that one can clearly see the Caribbean islands to the SW, while on the rest of the chart there are some scattered dots but it is very difficult to see if they are the Azores or not...

I searched "Mid atlantic ridge" and indeed it passes through the Azores, volcanoes etc, but as it meanders E-W-N-S in the middle of the Ocean it does not give any indications..


Does anyone know this chart ?
Or a way of finding somewhere the coordinates of the four corners of the chart ?


thanks
 

AndrewB

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BA4407 does NOT include any part of the Azores. The extremities of this chart are 41°22'30"N to 10°35'00"N; 63°35'00"W to 42°09'18"W.

Mine is the edition of 1979. Sometimes different editions of BA charts cover slightly different areas.

P.S. This chart is so empty I wonder why you need it. I used it for convenience for plotting sextant sights across the Atlantic - back in the days when one plotted sextant sights!
 
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Roberto

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thanks a lot for checking Andrew :)


btw I followed your trip on the sentinel web site since you were on the NE Brazilian coast, I went back there a few days ago to re-read your sail north from Salvador (tough) and the places you have been into on the NE coast, very interesting, next march is my turn


thank you, and fair winds :)





thinking of it, what' the use of an ocean chart having a few islands on one corner and just water on the rest of its surface ? Mid atlantic range... is it a chart for submarines only ?


addition: I see you added the same kind of thought :)
 
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Roberto

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Yes I bought it already

Gnomonica.jpg



though with that weird projection I have a lot of difficulties in getting used to such a non-Mercatorian view of the world: the UK at the latitude of Florida ? :cool:

The next Mercator chart of the Atlantic covers from northern Canada to halfway down south america, daily positions might be one mm apart, a most discomforting sight...
I would actually like a chart covering say the central third of this one...

4013.jpg



From the Acores to Channel/France/Gib this one looks good, plenty of alternative destinations to choose from in case weather is really bad :)

6623.png
 

tri39

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All you have to do is rotate it anticlockwise! And straight lines are great circles, ideal?!
I am following your trip since I'm planning something similar altho NA rather than SA.
 

AntarcticPilot

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The charts on this thread demonstrate very clearly one of the major disadvantages of the Mercator projection - the scale of the chart varies wildly with latitude. Over the span of latitudes from the equator to 50 N, the scale changes by 50% (scale factor = 1 at the equator, 1.55 at 50N). However, it's major advantage (that lines of constant bearing are straight lines) is not really useful for ocean navigation; we have long since passed the point where you have to sail along a bearing to get from A to B!
 
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