Author Topic: navigation lights  (Read 3894 times)

0 Members and 1 Guest are viewing this topic.

Terence

  • Newbie
  • *
  • Posts: 37
navigation lights
« on: October 27, 2014, 09:03:30 »
I'm confused a bit by the standards for mast lights, despite going through quite a few Forum Posts.  I have a Billings 1:33 Nederland plan and a Medcalf plan for the same tug, and the lamp colours given for the mast are different.  And the regulations stipulate different lighting for different lengths of vessel, and different again when towing another vessel etc.  I understood that the mast would show white all round for the Nederland, but Medcalf gives red to the stern lamps, white to the bow. (I thought all lights facing the stern were white ...)

ixion

  • Full Member
  • ***
  • Posts: 245
Re: navigation lights
« Reply #1 on: October 27, 2014, 09:50:55 »
On a tug there is a amber towing light above the white stern navigation light. This is only lit when towing.

Calimero

  • Sr. Member
  • ****
  • Posts: 268
    • Calimero's RC shed
Re: navigation lights
« Reply #2 on: October 27, 2014, 10:09:51 »
I found this site pretty helpful when setting up the lights on my Odin: http://www.bosunsmate.org/seamanship/lights.php

You may want to split lights in different groups so that you'll be able to switch them on/off by function: nav light, towing lights, restricted maneuverability, deck lights, bridge/wheelhouse light, search lights. Even if at first you don't switch them as separate groups, you might install a "multi switch" later on.

des

  • Sr. Member
  • ****
  • Posts: 408
Re: navigation lights
« Reply #3 on: October 27, 2014, 15:10:18 »
The only lights that should show "white all round" should be anchor lights (fore and aft), and the centre NUC light - all others should be screened in such a way as to limit visibility to certain specific arcs.

If your Nederland prototype is more than 150 ft in length, then you need two masts, with a masthead light on each, which must have a vertical separation of (I think, off the top of my head) 4m.  Otherwise you only need a single mast.  These masthead lights are screened so they only show from right ahead to 22.5 degrees abaft the beam on each side.

You also need two towing lights facing forward.  These are generally on the fore (lower) mast;  they must be spaced 2m vertically apart and 2m below the masthead light.  (Ixion is correct - you also need a yellow towing light facing aft, and located above the white stern light - these are not usually on a mast, but may be if no other location is suitable considering the working aft deck on a tug.)

You also need NUC lights - red / white / red, all round lights, spaced 2m vertically, and usually mounted on the main mast, but which can also be hoisted on a pennant halyard - depending on the original ship designer's intentions.

If your (prototype) vessel is also used for purposes other than towing (eg, fire fighting, dive support, pilotage, customs & border protection, air / sea rescue, shooting or recovery of nets, etc) then there also a host of other light combinations that your vessel may be required to show.  These may or may not be permanently installed on the vessel's mast, or may be hoisted on signal pennant halyards as the need arises.

Hope this helps.

Des.

des

  • Sr. Member
  • ****
  • Posts: 408
Re: navigation lights
« Reply #4 on: October 27, 2014, 15:50:52 »
For many of us, the required navigation lights for tugs is fairly straightforward;  but for others they seem to be quite confusing.  Here's a few other issues relating to navigation lights under different conditions, to give the "old salts" something to think about - I don't know the answers myself, so no prizes for any answers.

1 - Does a Dynamic Positioning Ship, holding a fixed position at a particular location, show anchor lights or under-way lights?  A non-DP vessel held in a fixed position by a 3- or 4-anchor bridle would clearly show anchor lights, so why wouldn't a DP vessel?

2 - Does a vessel operating an ROV beneath the surface show "Diver Below" flags as she clearly would if using divers instead of an ROV?

3 - Does a vessel slowly towing scientific instruments along a fixed course above the ocean floor (for example, for ocean floor mapping) show towing lights, or NUC lights to indicate a restriction in manoeuvrability?  (Clearly there is no such restriction in manoeuvrability - changing course or speed is possible, but highly inconvenient.)

4 - Does a submarine, operating on the surface (during peacetime) show any lights at all?  And if so, how does it raise the lights to the required elevation to achieve required visibility range?

Des.

Calimero

  • Sr. Member
  • ****
  • Posts: 268
    • Calimero's RC shed
Re: navigation lights
« Reply #5 on: October 27, 2014, 16:12:44 »
Not Under Command (Red over Red) and Restricted Ability to Maneuver (Red / White / Red) are two different things, according to COLREGs. I assume the same all-round lights could to be used (with middle white being on or off), making it even more painful to wire.

des

  • Sr. Member
  • ****
  • Posts: 408
Re: navigation lights
« Reply #6 on: October 27, 2014, 17:49:36 »
Yes, you are correct.  I only used the NUC term to group the RWR lamps for convenience, as they do form a group or pattern when mounted on the mast.  They do indeed indicate different conditions when in use.

Des.

Wishkah

  • Site Supporter
  • Jr. Member
  • *
  • Posts: 94
Re: navigation lights
« Reply #7 on: October 27, 2014, 18:09:18 »
Quote
4 - Does a submarine, operating on the surface (during peacetime) show any lights at all?  And if so, how does it raise the lights to the required elevation to achieve required visibility range?


I can speak for part of the submarine question. A submarine does display running lights. Port and Starboard lights are on the sail (fixed), the stern light is located on top of the rudder(fixed), A masthead light (location varies by class, on the radar mast on the boats I served aboard), and May show a Submarine ID beacon (Flashing Amber light 1 per second for 3 seconds then off for 3 seconds).

Cheers
Barry
Barry

Terence

  • Newbie
  • *
  • Posts: 37
Re: navigation lights
« Reply #8 on: October 28, 2014, 01:02:53 »
Thanks to all for information on navigation lights.  Since I'm new to model boats, I wanted to get the detail right, but it is clear that there are many variations possible.  So I'll stick to white mast lights with a yellow light facing aft.
Thanks
Terence

Capt.Towline

  • Site Supporter
  • Jr. Member
  • *
  • Posts: 81
Re: navigation lights
« Reply #9 on: October 28, 2014, 15:47:19 »
Terence, don’t bog yourself down too much; the various light configurations can be confusing but are also reasonably logical as they are there to indicate a vessels status to other seafarer’s. However, the responsibilities of vessels under the complexities of the collision avoidance regulations – or “Rules of the Road” – take considerable time to learn and master and there in lies the confusion of what lights to display and when. It would take some time to fully detail all configurations but I’ll try to simplify:
SECTORED LIGHTS
All power driven vessels when underway (not at anchor or made fast to the shore or aground) must show:
i) A white masthead light forward – sectored from 22.5degreees abaft one beam through ahead to 22.5 degrees abaft the other beam
ii) A second white masthead light – sectored as above – abaft and higher than the forward one for all vessels over 50m length (can chose to exhibit if <50m)
iii) Side lights – sectored from right ahead to 22.5 degrees abaft the beam; red on port side, green on stbd side.
iv) white stern light – sectored from 22.5 degrees abaft one beam, through astern to 22.5 degrees abaft other beam.
You’ll appreciate that no matter what angle you view the vessel from you’ll be able to work out the aspect of the vessel; whether you’re looking at it’s bow, port side, stbd side or stern. And that’s the importance, in order to determine your responsibilities in relation to your own vessel to avoid collision – is it a head on, crossing, overtaking etc situation. And because all vessels underway can move they have a responsibility  to act as either a ‘stand on vessel’ or ‘give way vessel’ and this is determined by the relative aspects of each vessel.

Towing Lights are only there to indicate the relationship between towing vessel and towed object. They also show the length of the overall potential hazard to other vessels so that if they are the give way vessel they can provide sufficient sea room to not cause concern to towing/towed vessels.
These lights are also sectored to maintain the ability to determine the aspect of the towing vessel:
i)   instead of the main white masthead light – two white masthead lights in a vertical line  with the same sectors for overall tow length  up to 200m
ii)   instead of the main white masthead light – three white masthead lights in a vertical line with the same sectors for tows of over 200m
iii)   side lights - as for vessel under way
iv)   stern light - as for vessel underway
v)   yellow towing light above the stern light and sectored the same as the stern light

Towed vessels/objects also need to display lights but this is a bit more complicated due to the various different compositions of tows/pushers/partly submerged objects.

ALL ROUND LIGHTS
They are all round to show a particular special condition, to any vessel, from any angle, to indicate a restriction of some sort:

At Anchor – not underway. Should show where can best be seen
i)   all round white light in fore part of vessel
ii)   at or near the stern an all round white light lower than the forward one.
iii)   For vessels less than 50m, instead of above, a single all round white where it can best be seen.
iv)   All can but over 100m shall also use deck lights to illuminate the vessel.

Aground – in addition to above two all round red lights in a vertical line where best can be seen – essentially Anchor and NUC combined

Not Under Command – a vessel which through some exceptional circumstance is unable to maneuver as required by the rules and is therefore unable to to keep out of the way of another vessel – shall exhibit:
i)   two all round red lights in a vertical line where best can be seen
ii)   when underway AND making way through the water, in addition to i), side lights and a stern light.

Restricted in her Ability to Manoeuvre – a vessel which due to the nature of her work is restricted in her ability to manoeuvre as required by these rules and is therefore unable to keep out of the way of another vessel – shall exhibit:
i)   Three all round lights in a vertical line – red over white over red
ii)   If making way through the water, additional to i), masthead lights, side lights and stern light

Constrained by her draught – power driven vessel which because of her draught in relation to available depth and width of navigable water is severely restricted in her ability to deviate from her course – In addition to lights for power driven vessel underway, three all round red lights in a vertical line where best can be seen.

In answer to Des:
1.   DP vessel is underway and should therefore show lights for this, but would show it’s Restricted in it’s Ability to Manoeuvre if necessary to demonstrate it’s limitations as defined above.
2.   ROV – no persons in the water so, not so restricted to take avoidance action. But if necessary and in accordance with the definition above could also exhibit RAM
3.   Long slow tow – Rule 27 states that a power driven vessel engaged in towing such as to severely restrict the towing vessel and her tow in their ability to deviate from there course, shall exhibit RAM – this would be in addition to the towing light requirements. But of course you are right, not all tows will be restricted in such a way.
4.   Barry’s answered this – it’s still a power driven vessel but as it’s low to the surface uses a flashing yellow to make it more visible

I hope I haven’t gone into too much detail to overburden you and certainly the light diagrams that Calimero has linked should make more sense with the above

Kind regards,
CT

des

  • Sr. Member
  • ****
  • Posts: 408
Re: navigation lights
« Reply #10 on: October 29, 2014, 14:31:10 »
Thanks Cap'n - there's stuff in your article that I hadn't picked up from reading the COLLREGS re lighting.

Des.