I've been baffled with these for a while. On the Long Island Sound, Eastern Part chart 12354TR, there are diagonal gridlines that go from SW to NE, and again from NW to SE. These are marked with numbers like 43910, 43920, 43930, 43940, 9960-Y-43950, and so forth. Are these some kind of LORAN lines? And, since LORAN has gone away (yes?), I assume I should simply disregard these lines, and that they no longer have any purpose.
Thanks for clearing it up for me!
Yes, those are lines that was once used with the Loran system. And as you know that system is no longer in use. so, for the purposes of this course simply disregard them as they have no functionality.