8 People on Fly Bridge?

My GB 32 weighs, all up, close to 20,000 pounds. Next month, during the SF Fleet Week air show, I will have a total of 8 people on the boat, including me.
SF Bay can get a bit windy and bumpy, and I remember reading of a few cases where powerboats capsized, apparently due to top-heavy overloading. 8 adult Americans probably weigh a total of over 1,500 pounds

So, may have your knowledge and/or thoughts about whether or not I need to limit the number of people on the fly bridge?

Thanks in advance.
Oldersalt

Oldersalt said:

My GB 32 weighs, all up, close to 20,000 pounds. Next month, during the SF Fleet Week air show, I will have a total of 8 people on the boat, including me.
SF Bay can get a bit windy and bumpy, and I remember reading of a few cases where powerboats capsized, apparently due to top-heavy overloading. 8 adult Americans probably weigh a total of over 1,500 pounds

So, may have your knowledge and/or thoughts about whether or not I need to limit the number of people on the fly bridge?

Thanks in advance.
Oldersalt

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Definitely, you do. My boat is bigger than yours and weighs 11tonne = 11,000 kg = 24,200 ibs, yet the official Queensland (Australia) Maritine Safety sticker on the windscreen says no more than 3, repeat, 3, on the fly-bidge. There is a formula somewhere you could try Googling. Sorry, a fair number will need to just stay below.

It is likely occupying the flybridge will be uncomfortable due to lots of rocking, particularly if anchored. Deck-level occupation will be more enjoyable. Why the need to be seven-feet taller when the airplanes will be at least a thousand feet above? A flybridge is an annoyance in typical SF waters. Regardless, why have everyone on the flybridge anyway? Reach up and touch??

markpierce said:

It is likely occupying the flybridge will be uncomfortable due to lots of rocking, particularly if anchored. Deck-level occupation will be more enjoyable. Why the need to be seven-feet taller when the airplanes will be at least a thousand feet above? A flybridge is an annoyance in typical SF waters. Regardless, why have everyone on the flybridge anyway? Reach up and touch??

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Ummm...why would everyone want to be on the flybridge? For the very reason they were designed in the first place; to get a better view!
I'm detecting a little flybridge envy here.

I would say yes 8 people would be to much.


With 8 people on the fly bridge that is a great deal of weight that would be moving around.


Mark, brings up a good point!


Cheers.


H.

I'm not a marine architect and I didn't stay at a Holiday Inn last night. But I'd say this - It's like the question of, "When should I reef my main?"
Answer, "When it first crosses your mind."

Your gut's telling you 8 is too many. You're probably right.

boomerang said:

I'm detecting a little flybridge envy here.

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Oh geez....no....please no.... here comes the flybridge/no flybridge thread...

My boat is smaller than yours and used to have a decal limiting the flybridge to six people. The decal has faded away but that's irrelevant.

It's important to remember that "people" can vary greatly in weight. Also remember that sitting and all rushing to one side to see something can be two vastly different situations.

Eight people on the flybridge in a slip at a marina and eight people on the flybridge in an open bay are two different situations as well.

My opinion; don't do it. Put them in the cockpit or on the foredeck.

I don't think it would be a real problem. I've had more than that on the bridge of my old Mainship.

WesK said:

My boat is smaller than yours and used to have a decal limiting the flybridge to six people. The decal has faded away but that's irrelevant.

It's important to remember that "people" can vary greatly in weight. Also remember that sitting and all rushing to one side to see something can be two vastly different situations.

Eight people on the flybridge in a slip at a marina and eight people on the flybridge in an open bay are two different situations as well.

My opinion; don't do it. Put them in the cockpit or on the foredeck.

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Wes, I suspect that 6 people up on the fly-bridge of your boat, if smaller than the OP's, would be decidedly risky, as that is double that recommended for my 11tonne 34 footer. (see my post #2 above) Although I think the 'official' number of 3 for my boat is a bit conservative, and I would have no issue with 4 in smooth waters. But 8 on a 32 footer - no way.

Peter B said:

Wes, I suspect that 6 people up on the fly-bridge of your boat, if smaller than the OP's, would be decidedly risky, as that is double that recommended for my 11tonne 34 footer. (see my post #2 above) Although I think the 'official' number of 3 for my boat is a bit conservative, and I would have no issue with 4 in smooth waters. But 8 on a 32 footer - no way.

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The sticker said six. I had five or six up there on a short "ride" on the AICW behind Myrtle Beach, SC. It's basically a canal there. And they were "small" people. The rest were on the foredeck.

Other than the sticker, it's a judgement call. There's no way I would put six up there in open water and there are times when even I go below to run the boat.

As the captain, you are responsible for everyone's safety.

8 people probably weigh in the region of 1,250-1,500lb vs boat of 20,000lb.
I think the risk you run is primarily that the boat becomes unstable because all 8 want to see the same event moment from exactly the same position on the boat. 1,500lb moving suddenly to one side would be enough (IMO) to rock the boat seriously. While this might well not be enough to cause a rollover/capsize, it could well be enough to throw unsuspecting (older/weaker?) people into the water. Then all hell will break loose!!

Oldersalt said:

My GB 32 weighs, all up, close to 20,000 pounds. Next month, during the SF Fleet Week air show, I will have a total of 8 people on the boat, including me.
SF Bay can get a bit windy and bumpy, and I remember reading of a few cases where powerboats capsized, apparently due to top-heavy overloading. 8 adult Americans probably weigh a total of over 1,500 pounds

So, may have your knowledge and/or thoughts about whether or not I need to limit the number of people on the fly bridge?

Thanks in advance.
Oldersalt

Click to expand...

If you had a 50' boat with 15' beam then the FB would probably be spacious enough to comfortably [and safely] accommodate up to 8 people max. But you don't. In your case, I believe four persons should be max for many reasons. Have the passengers alternate position in boat.

Quote:
Originally Posted by markpierce
It is likely occupying the flybridge will be uncomfortable due to lots of rocking, particularly if anchored. Deck-level occupation will be more enjoyable. Why the need to be seven-feet taller when the airplanes will be at least a thousand feet above? A flybridge is an annoyance in typical SF waters. Regardless, why have everyone on the flybridge anyway? Reach up and touch??

boomerang said:

Ummm...why would everyone want to be on the flybridge? For the very reason they were designed in the first place; to get a better view!
I'm detecting a little flybridge envy here.

Click to expand...

I believe Mark would feel uncomfortable on a flying bridge. The unobstructed 360° sky-view and the complete bow to transom corners boat view for Mark seems to go past his plate of desires. Obviously due to his statement: "... flybridge will be uncomfortable due to lots of rocking, particularly if anchored." He enjoys stable footings while aboard a boat. Unfortunately boats have natural tendency to move around a bit. that's why you get what's called your "Sea Legs!"

Why he mentions... "A flybridge is an annoyance in typical SF waters. Regardless..." is a complete wonder to me. I'd like to hear Mark expound a bit on that remark. Mark - FB being "an annoyance in typical SF waters" - What do you really mean???

From our 20k lbs 39 ft boat


We've done around this many at the dock but I wouldn't out on the water.

8 folks up top would not bother me at all.

I would watch the movement of the folks and ask they would not all rush to a rail at once.

With the open viewing area , nothing would be gained by charging from side to side .

Sea conditions would count. The extra weight up top would slow the roll , but it would go further.

I think the folks would abandon the area as the roll became a PIA , when they had to hang on.

Be observant , but it should be a nothingburger.

15 years ago I checked with Krogen's architect and the weight limit for the upper deck was 750 lbs before stability was affected. I have frequently violated this limit (the dinghy, motor, gas and spares etc on the upper deck alone are 350 lbs) when at anchor in calm waters, but not underway.

A few years ago a Silverton rolled over on the East Coast during a fireworks display due to too many people on the fly bridge. A similar incident occurred off Vancover Island recently when a whale watching vessel rolled over. Lives were lost in both cases.

Ferries roll over when passengers rush to one side with alarming frequency. Up top weight transfer to a lower location during blue water cruising is normal procedure. Think moment arm. Sailing racers grasp the placement of weight, see all those bodies on the high side?

In SF Bay an unsettling stray current wave can appear pretty quickly. Especially when the skipper is watching airplanes.

Why don't you call your insurance agent?

Perhaps I'm incorrect with this thought... but, in a general engineering sense... it seems to me:

Regarding same length boat...


Fairly wide waterline berth, hard chine planning hull shape would have less "roll-over" tendency that a more narrow waterline berth, soft chine full displacement hull shape.

Art said:

Perhaps I'm incorrect with this thought... but, in a general engineering sense... it seems to me:

Regarding same length boat...


Fairly wide waterline berth, hard chine planning hull shape would have less "roll-over" tendency that a more narrow waterline berth, soft chine full displacement hull shape.

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Art me Irish Bro. I would agree with that.

Cheers Mate.

H.

Oldersalt said:

My GB 32 weighs, all up, close to 20,000 pounds. Next month, during the SF Fleet Week air show, I will have a total of 8 people on the boat, including me.
SF Bay can get a bit windy and bumpy, and I remember reading of a few cases where powerboats capsized, apparently due to top-heavy overloading. 8 adult Americans probably weigh a total of over 1,500 pounds

So, may have your knowledge and/or thoughts about whether or not I need to limit the number of people on the fly bridge?

Thanks in advance.
Oldersalt

Click to expand...

Your GB 32 is 11.0 ft wide. You have wide side decks, so your FB is ~8 ft wide. You will feel crowded with 8 avg size Americans up top. Let that feeling of a crowd be your guide.

With your wide side decks, there is less danger of having too much weight too close to one side, but the same narrow side decks prevent getting some of the weight far enough from the low side to compensate.

hfoster said:

Art me Irish Bro. I would agree with that.

Cheers Mate.

H.

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H me Irish Bud!

Of course you would! Being that we're Irish, nearly always on plane, gots wide berth arm reach and hard as heck to tip over. Besides... we're 100% self righting! - LOL

Double Cheers! - Art

How much permanent seating did the manufacture install? If this were a USCG inspected boat that would come into play. It’s not, but it’s still a clue. Non-permanent seating on the flying bridge seems inadvisable in a seaway.

None of us know without doing the stab calcs and knowing weights and sea conditions.

Gut feel is queasy with 8 up there. And crowded to boot. Keep half in cockpit or on foredeck.

I was there at the SF Fleet Week last year when the boat capsized with ~20 people aboard. Capsizing is a real risk and over- or misloading is a prime cause.

Somewhere I have a photo of Markpierce on my 34 LRC flybridge at the SF Fleet Week 2012. It must have been a traumatic experience for him to feel the way he says he feels. It was rolly that day on the bay.

My general rule with children is no FB access in the bay due to my concern for their safety while traversing the ladder and the exaggerated rolling motion up there. I would limit adults to 3-4 at the most under benign bay conditions.

Ask yourself, "What are the risks and what are the benefits? Do the benefits outweigh the risks?" If not, don't do it.

Rolly Polly! 3 on bridge!

Apart from other safety considerations already discussed, do not under estimate the risk from wakes thrown up by inconsiderate go-fast boats in your vicinity. This sounds like a boat "party" environment with drinking and horse play involved. Best be safety focused.

i'm in the minority here, but back in the day i had 8 on the bridge of my 32 GB many times on SF bay without a problem. you could be sure your fuel and water tanks are topped off for added stability.

2009 I was honored to take a small film crew into SF Bay... for a film-report preview about the then news worthy item of illegally harvesting shark fins.

We left San Rafael and went to East Brother Island area. They had 5 persons with film equipment. We spent a few hours all on the fly bridge of my 31' Uniflite.

Weather was calm. Didn't experience any tippy feeling.