Adding second set of side navigation lights

[Montanan]

Originally Posted by FabioC

I have a 2016 SO 349, but the new ones have the same configuration and the SO 41 is also the same (at least until 2019, which is the most recent I saw).

The mast-mounted nav lights are mounted approximately at mid height of the mast.

It is an undesirable location, not only because they do get hidden by the head sails and spinnakers, but also because they get knocked off by the halyards (if you secure the lazy halyards at the base of the mast - I talked to other Jeanneau owners, everyone I talked to has lost those lights at least once...), or if you have an overlapping genoa, it may get hit by the sail during a tack, or if you hoist the spinnaker in the shadow of the main, or... This latter issue can be partially resolved by installing a light guard around the fixture, but even the guard does not completely eliminate the possibility of a halyard hitting it just the right way to knock it off. The thing is that often you realize they are gone when you need them, you go to turn them on, look up, and there is nothing there... I guess this is one of those things in life, you just have to accept it... still, a PITA, not sure why it was designed like this.

Okay, so mystery partially solved as to where the sidelighting is placed on the OS boats.

Definitely an inappropriate [and illegal] location given it is obscured by any and all headsails.

And yeah, readily prone to be damaged.

Your SO 349
Length overall:
10.34 m / 33'11"

As to the SO 41
Length overall:
12.34 m / 40'6"

And if that light depicted in the images I linked in my prior post that is about halfway up the mast is a combination of masthead light and navigation sidelights then the white steaming light is definitely not placed vertically high enough up above the navigation lights, hence illegal at least for US Federal Code.

I do not see in the Jeanneau pictures two distinct sets of lights on the mast of the OS boats, just the one which I though was a combination masthead light for use when motoring and a deck illuminating light.

Specifically, US.C.F.R. 84.03 Vertical positioning and spacing of lights

(d) The masthead light, or the all-round light described in Rule 23(c), of a power-driven vessel of less than 12 meters in length shall be carried at least one meter higher than the sidelights.

Oddly the C.F.R. has specific rules for boats larger than 20 meters and also for less than 20 meters but no specific rules for 12 to 20 meters.
. . .

anyway, the following applies

(g) The sidelights of a power-driven vessel shall be placed at least one meter lower than the forward masthead light. They shall not be so low as to be interfered with by deck lights.

[Montanan]

Originally Posted by jacktheflyer

I helped a friend sail his new purchase to his home port. This has been the only sailing catamaran I've seen with side lights which were just forward of the shrouds on the topsides. I found the glare of the red and green off the topsides ruined my night vision.

The catamarans shroud mounted sidelights were not properly inboard screened. That would be hazardous and annoying.

There is a law for most everything that is of ill consequence, including such misattribute.

US C.F.R.

84.09 Screens


(a) The sidelights of vessels of 20 meters or more in length shall be fitted with mat black inboard screens and meet the requirements of � 84.17. On vessels of less than 20 meters in length, the sidelights, if necessary to meet the requirements of � 84.17, shall be fitted with mat black inboard screens. With a combined lantern, using a single vertical filament and a very narrow division between the green and red sections, external screens need not be fitted.

(b) On power-driven vessels less than 12 meters in length constructed after July 31, 1983, the masthead light, or the all-round light described in Rule 23(c) shall be screened to prevent direct illumination of the vessel forward of the operator's position.

[KP44]

I had deck-level navigation lights.
I installed an additional tri-color LED at the mast top and added a set of LED nav lights near the original nav lights.
Of course, all three sets of nav lights are wired separately and only one set is used at any time. I kept the original lights because they have less radio interference than some LEDs. If radio or radar is critical, I can turn off LEDs and still have legal and good nav lights.

[The Perfessor]

I have experience using battery operated nav lights: once, when a wire broke in heavy weather, and another time when the bulb filament broke in heavy weather. I have a set that I use for the dinghy and found that I've used it more in emergency for my big boat, then I ever have for the dingy. They're inexpensive, but work great.

And as you can see from other postings, running two sets of nav lights is a big No-No.