It’s hard to capture the angle of the bow in tight quarters, but I’m looking for opinions as to whether or not the angle of the hull points down too far for shark eye nav lights to be effective here at the bow.
What do you all say?
Shark Eye Nav Lights
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Re: Shark Eye Nav Lights
You'll need to fab a shim to meet the distance rules for that.
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Re: Shark Eye Nav Lights
To angle the beam up rather than pointing at the water?fallguy1000 wrote: ↑Tue Sep 13, 2022 6:02 pm You'll need to fab a shim to meet the distance rules for that.
That might not be the end of the world. Best before paint I suppose.
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Re: Shark Eye Nav Lights
The distance rule is forward. So, consider a 10 degree angle, for semantics.
If the light is rated for one mile...the beam is on the 10 degree down angle for a mile, but it can't make it a mile because the boat is say 3' above the water, so the beam angle is constrained.
Cos (80) = 0.17365
0.17365 = 3/beam constraint
beam constraint is 3/0.17365 or 17' only
Of course light never travels in a straight line, but hopefully the graphic will help. You are getting a fine or warning if I'm the CO because the beam will be really, really weak on the rating requirement. It won't be good.
If the light is rated for one mile...the beam is on the 10 degree down angle for a mile, but it can't make it a mile because the boat is say 3' above the water, so the beam angle is constrained.
Cos (80) = 0.17365
0.17365 = 3/beam constraint
beam constraint is 3/0.17365 or 17' only
Of course light never travels in a straight line, but hopefully the graphic will help. You are getting a fine or warning if I'm the CO because the beam will be really, really weak on the rating requirement. It won't be good.
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Re: Shark Eye Nav Lights
I am mounting mine there and used the gasket for template to cut hole in the side, then tapered the hole with a backing to get the required side/aft angle view correct. They are LED and are designed to be mounted on the side of the hull.
"that it isn't just an ordinary sort of boat. Sometimes it's a Boat, and sometimes it's more of an Accident. It all depends." "Depends on what?" "On whether I'm on the top of it or underneath it."
A. A. Milne
A. A. Milne
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Re: Shark Eye Nav Lights
My navs are a bit concerning for me. They are a bit far apart. An oncoming vessel would be able to miss both and come right in under.
Shark eyes are really at risk in smaller boats...the distance above docks and posts is not great..
I had second thoughts on these. Mine are angle a bit in, but hoping that would reduce oncoming hit.
Shark eyes are really at risk in smaller boats...the distance above docks and posts is not great..
I had second thoughts on these. Mine are angle a bit in, but hoping that would reduce oncoming hit.
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Re: Shark Eye Nav Lights
Most nav lights are designed to accommodate different angles the bow will be from a trolling speed to getting on plane to planning speed. They use multi-faceted reflectors so the light can be seen at a lot of different angles.
"that it isn't just an ordinary sort of boat. Sometimes it's a Boat, and sometimes it's more of an Accident. It all depends." "Depends on what?" "On whether I'm on the top of it or underneath it."
A. A. Milne
A. A. Milne
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Re: Shark Eye Nav Lights
Fallguy, why wouldn't yours be correct? A lot of large boats have the nav lights mount on the sides of the cabin. A boat coming head on towards you will see all 3 lights and know he is headed straight at you. By the time he gets close enough see the distance the nav light are apart, there should already be corrections made in course.
"that it isn't just an ordinary sort of boat. Sometimes it's a Boat, and sometimes it's more of an Accident. It all depends." "Depends on what?" "On whether I'm on the top of it or underneath it."
A. A. Milne
A. A. Milne
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Re: Shark Eye Nav Lights
Well, mine are technically over zero degrees, say 3-5 degrees in. The surveyor said technically I could get called on it, but I like it because a vessel far away should be able to see both. At 636' away, using 3 degrees, both lights should be visible, then one would vanish, on a course one way or the other.OrangeQuest wrote: ↑Tue Sep 13, 2022 6:28 pm Fallguy, why wouldn't yours be correct? A lot of large boats have the nav lights mount on the sides of the cabin. A boat coming head on towards you will see all 3 lights and know he is headed straight at you. By the time he gets close enough see the distance the nav light are apart, there should already be corrections made in course.
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Re: Shark Eye Nav Lights
ps...I doubt 636' accurate...a theory and sorry Dan, I'll shut up now
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