Night Coastal Navigation

[gyork]

Has anyone observed and/or utilized the "sector" light projections from beacons/lighthouses, whilst nighttime navigating? Refer to the white sector emanating from Goose Rocks Light, at Fox Island Thoroughfare, Vinalhaven. http://www.charts.noaa.gov/OnLineViewer/13305.shtml

Gary

[EEL]

Has anyone observed and/or utilized the "sector" light projections from beacons/lighthouses,

I have seen them, but that is about it. After all, I never figured out the identity of the various flashing lights to the south of Jewell and one of those is supposedly sectored as I recall. Maybe on this year's trip.

Ed Lawson

[PeterB]

Has anyone observed and/or utilized the "sector" light projections from beacons/lighthouses, whilst nighttime navigating? Refer to the white sector emanating from Goose Rocks Light, at Fox Island Thoroughfare, Vinalhaven. http://www.charts.noaa.gov/OnLineViewer/13305.shtml

Gary

I have. What do you need to know?

[gyork]

Just wondering, Peter, if you found them to be accurate, as best as you can deduce from the chart.

Gary

[EEL]

Just wondering, Peter, if you found them to be accurate, as best as you can deduce from the chart.

Since they are used to warn of dangers or to delimit fairways for vessels, they must be sufficiently accurate for navigation. The Goose Rocks Light, which has a 3 degree white sector, is the means of finding the fairway for the eastern approach to Fox Island Throrofare. FWIW, check out the Brown's Head Light which is a sectored light (RWR) for the western fairway and Portland Head light which is three sectored (RWG) for the fairway to the main channel into Portland.

Here is a cautionary point from Coastal Pilot: "Where lights have different colored sectors, be guided by the correct bearing of the light; do not rely on being able to accurately observe the point at which the color changes. On either side of the line of demarcation of colored sectors there is always a small arc of uncertain color."

This navigation stuff is great fun to explore in winter. Thanks for giving me a chance to open up the Coastal Pilot...creates dreams of summer adventures.

Ed Lawson

[PeterB]

Since they are used to warn of dangers or to delimit fairways for vessels, they must be sufficiently accurate for navigation. The Goose Rocks Light, which has a 3 degree white sector, is the means of finding the fairway for the eastern approach to Fox Island Throrofare. FWIW, check out the Brown's Head Light which is a sectored light (RWR) for the western fairway and Portland Head light which is three sectored (RWG) for the fairway to the main channel into Portland.

Gary,

I didn't cross check for accuracy: I was passing across the white sector (not using it to be guided into a harbor) so it was one more cue as to where I was along my course. I assumed it to be accurate, as Ed says, since its used to warn of dangers and delimit fairways. Since lighthouses are fixed objects on land, unlike buoys, it would be reasonable to assume they're set up accurately and remain so.