Any Issue(s) with Installing Arch for Solar at Stern

[NaClyDog]

Are there any concerns or issues with respect to ocean sailing safety / stability for vessels that have a solar arch at the stern?


Long story short, looking at a couple of older heavy displacement 45'-ish sailboats which have no solar. Considering them will be out of the question if I cannot add a fair amount.


Thanks in advance.

[GreenWave]

Certainly doable as many have done it. Just need a good design and fabricated arch coupled with quality install.

[NaClyDog]

Originally Posted by GreenWave

Certainly doable as many have done it. Just need a good design and fabricated arch coupled with quality install.

Right, just because people do it doesn't necessarily mean it's safe or advisable.


That's just what I'm trying to figure out.


Thanks.

[Searles]

Stability has verry little to do with displacement of a vsl ,a targa for solar panels plus the accumulation of ariels etc will generally effect a smaller vsl say between 20 to 25 ft than 30 ft plus as a general rule check design and stability first if in dought .⛵️⚓️

[Tetepare]

In general you’re OK. You can do it with 1” tubing bolted to the rails, which is flimsy but works. Or 2” bolt to the deck, with backing plates. Or use a 3” welded frame through the deck and fixture to the subframe. Or a combination. That’s where I am, trying to determine how I want to do it.

[Bobby Lex]

“Stability” as in: will an arch make my boat tippy? No, not if your boat is a 45 ish foot displacement sailboat as you describe it to be.

As has been pointed out — despite your dismissal of the point — arches on sailboats are very common. They wouldn’t be so common if they were problematic as a rule. Search these forums and see whether a significant number of folks are saying they are a bad idea.

Aesthetically I’m not fond of how they detract from the lines of a pretty boat. But from a functionality perspective they are invaluable. Obviously they need to be designed, engineered and installed well.

I sure wouldn’t give mine up.

Bob

[ItDepends]

There are very few cases where "stability" would be affected by a properly designed and built arch. Especially if it is built out of aluminum instead of stainless steel. But...

(There is always a but, right?) There ARE issues. How those issues affect YOU depends on how you are going to be using your boat.

An arch adds a lot of windage. Not enough to seriously affect the sailing capability of the average cruising yacht, but in the case of extremely severe weather, the arch becomes a obvious liability. In tropical storm force or stronger winds, the drag added from the arch structure is significant. Solar panels mounted to the arch might not survive.

The weight might not effect the roll stability of the boat, but it can have a significant impact on the trim, and the boat's pitching motion. I have seen a lot of boats with so much crap added to their arches that they sit many inches down at the stern. That's BAD. Altering the fore and aft trim of a well balanced boat in that way can significantly affect helm balance, and turn a well mannered sailor into one with significant lee helm.

Any weight added to the ends of the boat can cause the boat to "hoppy-horse" in waves by greatly increasing the rotational momentum around the pitch axis.

Now, in MOST cases the excess weight is from a dinghy hanging on davits from the arch. Do NOT do that.

All that aside, I DID add simple aluminum arch (90 lbs) to my 53 foot boat just to carry solar panels. I know what my tradeoffs are. On a smaller boat the tradeoffs get bigger.

[Rohan]

I installed flexible panels on mine, so no need for an arch. You could go that direction instead.