PeteAlbright wrote:
On ships with "all around" lights mounted close on the mast, it is common to
have two lights mounted on each side of the mast. Two lights mounted 12"
apart should not be confusing, and while a sail may block a light, it would
also be illuminated by it.

Pete Albright
Tampa, FL

I'd be careful on this. Although I won't disagree that on some ships,
this is true, due to considerations of construction, this requires
regulatory agreement and is not the norm.
Also, it is quite possible that some may see various signal light
"trees" on either side of a ship mast, which they may mistake for
duplication, wherein reality, they are separate signals for some
specific locale or function.

otn

Both Pete and otn are right. On the one hand, most large vessels have
spare lights, at least for the major functions (stern, masthead,
sidelights, towing), so what might appear to be a pair of lights are
actually not used at the same time.

But, the US rules, at least, (I can't find an International Rules
citation for this) permit two lights to be used for one all around
light where there's a mast in the way, see 84CFR17 Annex I, paragraph
9 http://www.access.gpo.gov/nara/cfr/w...3cfr84_99.html

Basically, you have to ensure that the two lights appear as if they
are one at a distance of one mile or more by using screens or mounting
them close together.

Jim Woodward
www.mvfintry.com

otnmbrd wrote in message ink.net...
PeteAlbright wrote:
On ships with "all around" lights mounted close on the mast, it is common to
have two lights mounted on each side of the mast. Two lights mounted 12"
apart should not be confusing, and while a sail may block a light, it would
also be illuminated by it.

Pete Albright
Tampa, FL

I'd be careful on this. Although I won't disagree that on some ships,
this is true, due to considerations of construction, this requires
regulatory agreement and is not the norm.
Also, it is quite possible that some may see various signal light
"trees" on either side of a ship mast, which they may mistake for
duplication, wherein reality, they are separate signals for some
specific locale or function.

otn

I went through this same thought process a few years ago. What interested me
was the ability to have lights that would be visible, at the same time, both
down low for boats and up high for ships.

I have seen them used on a few training ships and tall ships. Usually there is
just one light mounted on a strut a few inches forward of the mainmast, one or
two meters apart, which would give a blind spot for a few degrees aft. This
might seem like a concern, except that the stern light is still visible directly
aft, so it's not like the boat has no aft lights showing at all. And as for
sail vs power, ANY boat behind you is a give-way boat, so all that matters is
that they see you.

In my case I could't readily come up with a good design for struts to mount the
lights away from the mast a few inches, so that's where I left it. But I still
think it's a good idea, and may get back to it some day.

Steve Christensen

When I was refering to "ships", I meant commercial ships, usually well over
60 M. Most of the lamps are 120 Vac. The ships are under IEEE-45, USCG (Code
of Federal Regulations), and ABS (or other certification organization)
rules.

On ships and tugs ("ocean going tug/barge"), the port, starboard, stern,
masthead, and range lights are redundant, with two lights in a vertical
assembly. Both lights have the wiring and filement monitored, and if the
primary light fails, the spare can be switched on.

On smaller masts, 6" to10" pipe, the "upper red", "middle white", and "lower
red" NUC lights are usually sigle, and mounted off the mast to the side.
Anchor lights are also mounted off the side if there is not room on top.
Where the mast is large, mounting two lights is theusual method.

Most of the ("ocean going tug/barge") barge lights are powered from local
batteries with solar panels, and have six lamps with automatic lamp
changers. One light that is not in the rules, is a small directional blue
light, facing aft at the bow (usually behind the range light). The tug pilot
uses this light to locate the boy of the barge at night.

Whether Red over green is necessary, on a sailboat, is up to the master. I
had not though of doing it on my '77 Hunter 30, But I do have all Aqua
Signal series 40 lights, the brightest 12 volt light commonly available.

Pete Albright


"Jim Woodward" wrote in message
om...
Both Pete and otn are right. On the one hand, most large vessels have
spare lights, at least for the major functions (stern, masthead,
sidelights, towing), so what might appear to be a pair of lights are
actually not used at the same time.

But, the US rules, at least, (I can't find an International Rules
citation for this) permit two lights to be used for one all around
light where there's a mast in the way, see 84CFR17 Annex I, paragraph
9 http://www.access.gpo.gov/nara/cfr/w...3cfr84_99.html

Basically, you have to ensure that the two lights appear as if they
are one at a distance of one mile or more by using screens or mounting
them close together.

Jim Woodward
www.mvfintry.com

otnmbrd wrote in message
ink.net...
PeteAlbright wrote:
On ships with "all around" lights mounted close on the mast, it is
common to
have two lights mounted on each side of the mast. Two lights mounted
12"
apart should not be confusing, and while a sail may block a light, it
would
also be illuminated by it.

Pete Albright
Tampa, FL

I'd be careful on this. Although I won't disagree that on some ships,
this is true, due to considerations of construction, this requires
regulatory agreement and is not the norm.
Also, it is quite possible that some may see various signal light
"trees" on either side of a ship mast, which they may mistake for
duplication, wherein reality, they are separate signals for some
specific locale or function.

otn

I think your 60M estimate is high. When we were looking for Fintry,
almost all of the 75-100' vessels we considered had dual masthead,
stern, and side lights with a control box that sounds a buzzer when
one goes out. Fintry's lights have dual supplies, as well -- the
primary light is 220V and the secondary 24V from the emergency
batteries. (These were all ex commercial, military, fishing, and
government vessels -- see www.mvfintry.com/boatsnotbought.htm for some
of them).

I agree that many "all-around lights" on working vessels are provided
by single lamps on a stalk away from the mast. Many of them appear to
violate Colregs Annex I 9(b) which requires the obstruction from a
mast be limited to six degrees (tangent 6 degrees is about 1/10, so a
six inch mast would require a sixty inch stalk -- the filament is a
vertical line source, so the width of the lens doesn't count). Note
that this does not apply to an anchor light, which must be placed
"where it can best be seen".

Fintry's NUC lights are pairs on either side of a 4" mast (see
http://www.mvfintry.com/pix/plymouth800.jpg -- they're below the
spreaders). They're 360 lights and don't have any screens. Since they
were installed for the use of the Royal Navy to meet the requirements
of the MCA, I would guess that they're probably legal, at least in the
UK.

While we're on the topic, have any of you noticed that many yachts
above 20 meters don't have legal lights -- the sidelights are often in
front of the steaming lights? While this is perhaps understandable in
the case of sail boats -- there's no good way to meet the rules when
you have an overlapping genoa -- it's also common in power yachts.
Fashion is more important than safety.

Jim Woodward
www.mvfintry.com

"PeteAlbright" wrote in message . com...
When I was refering to "ships", I meant commercial ships, usually well over
60 M. Most of the lamps are 120 Vac. The ships are under IEEE-45, USCG (Code
of Federal Regulations), and ABS (or other certification organization)
rules.

On ships and tugs ("ocean going tug/barge"), the port, starboard, stern,
masthead, and range lights are redundant, with two lights in a vertical
assembly. Both lights have the wiring and filement monitored, and if the
primary light fails, the spare can be switched on.

On smaller masts, 6" to10" pipe, the "upper red", "middle white", and "lower
red" NUC lights are usually sigle, and mounted off the mast to the side.
Anchor lights are also mounted off the side if there is not room on top.
Where the mast is large, mounting two lights is theusual method.

Most of the ("ocean going tug/barge") barge lights are powered from local
batteries with solar panels, and have six lamps with automatic lamp
changers. One light that is not in the rules, is a small directional blue
light, facing aft at the bow (usually behind the range light). The tug pilot
uses this light to locate the boy of the barge at night.

Whether Red over green is necessary, on a sailboat, is up to the master. I
had not though of doing it on my '77 Hunter 30, But I do have all Aqua
Signal series 40 lights, the brightest 12 volt light commonly available.

Pete Albright

Subject: Red over green mast lights for sailboat
From: "PeteAlbright"

On ships and tugs ("ocean going tug/barge"), the port, starboard, stern,
masthead, and range lights are redundant, with two lights in a vertical
assembly. Both lights have the wiring and filement monitored, and if the
primary light fails, the spare can be switched on.

On smaller masts, 6" to10" pipe, the "upper red", "middle white", and "lower
red" NUC lights are usually sigle, and mounted off the mast to the side.
Anchor lights are also mounted off the side if there is not room on top.
Where the mast is large, mounting two lights is theusual method.

What you describe above, is RAM, not NUC.
On ships, you will frequently find the anchor lights mounted on seperate
"poles" (sometimes portable) where the light will be at the top of the pole
.....normally a single light. BG try picking out the anchor lights on a ship,
nowadays ..... where they also use all decklights, the anchor lights tend to
just blend in with the others.

Most of the ("ocean going tug/barge") barge lights are powered from local
batteries with solar panels, and have six lamps with automatic lamp
changers.

Interesting .... never seen one with any kind of lamp changer.

One light that is not in the rules, is a small directional blue
light, facing aft at the bow (usually behind the range light). The tug pilot
uses this light to locate the boy of the barge at night.

Called a "steering light", it's frequently found on most ships, in a centerline
position as far forward as possible.
BTW, it seems nowadays, that most have stopped referring to Masthead and Range,
just using Masthead. The Range light was always the after of the two lights,
when it's usage was common.

Shen

Pardon my grammer, I ment that the ships I work on are usually all over 60
M, not that the light configuration applied to ships over 60 M.

Pete

"Jim Woodward" wrote in message
om...
I think your 60M estimate is high. When we were looking for Fintry,
almost all of the 75-100' vessels we considered had dual masthead,
stern, and side lights with a control box that sounds a buzzer when
one goes out. Fintry's lights have dual supplies, as well -- the
primary light is 220V and the secondary 24V from the emergency
batteries. (These were all ex commercial, military, fishing, and
government vessels -- see www.mvfintry.com/boatsnotbought.htm for some
of them).

I agree that many "all-around lights" on working vessels are provided
by single lamps on a stalk away from the mast. Many of them appear to
violate Colregs Annex I 9(b) which requires the obstruction from a
mast be limited to six degrees (tangent 6 degrees is about 1/10, so a
six inch mast would require a sixty inch stalk -- the filament is a
vertical line source, so the width of the lens doesn't count). Note
that this does not apply to an anchor light, which must be placed
"where it can best be seen".

Fintry's NUC lights are pairs on either side of a 4" mast (see
http://www.mvfintry.com/pix/plymouth800.jpg -- they're below the
spreaders). They're 360 lights and don't have any screens. Since they
were installed for the use of the Royal Navy to meet the requirements
of the MCA, I would guess that they're probably legal, at least in the
UK.

While we're on the topic, have any of you noticed that many yachts
above 20 meters don't have legal lights -- the sidelights are often in
front of the steaming lights? While this is perhaps understandable in
the case of sail boats -- there's no good way to meet the rules when
you have an overlapping genoa -- it's also common in power yachts.
Fashion is more important than safety.

Jim Woodward
www.mvfintry.com

"PeteAlbright" wrote in message
. com...
When I was refering to "ships", I meant commercial ships, usually well
over
60 M. Most of the lamps are 120 Vac. The ships are under IEEE-45, USCG
(Code
of Federal Regulations), and ABS (or other certification organization)
rules.

SNIP

Pete Albright