What is the point of ribs?

[udihow]

Lately I've been searching a lot on google, looking through every relevant web page I could find but there doesn't seem to be any simple answer. There must be something I'm missing.

More specifically; what function do the tubes really have?

I get it that they offer buoyancy on smaller ribs. But with larger ones where tubes barely touch the water or often not at all, they cant possibly offer any flotation or stabilization? Unless they are filled with gas that is lighter than air. And, apparently, ribs tend to float even if the tubes are empty, as if they weren't really needed.

As an example, take a 5m+ rib with alu hull. If you then, theoretically, removed the tubes and just extended the alu hull to compensate, what difference would it make? Compared to a similar sized 'traditional' boat with a similar glass fiber/grp/alu v-shaped hull.


Only reason I could find after reading though tons of general information, is that they are a "shock absorber" when you bump into other boats.... That can't surely be the only reason to carry around complicated pressurized tubes that needs careful special maintenance.

Can someone explain this to an uninitiated and uneducated idiot?

[Andre]

Originally Posted by udihow

Lately I've been searching a lot on google, looking through every relevant web page I could find but there doesn't seem to be any simple answer. There must be something I'm missing.

More specifically; what function do the tubes really have?

I get it that they offer buoyancy on smaller ribs. But with larger ones where tubes barely touch the water or often not at all, they cant possibly offer any flotation or stabilization? Unless they are filled with gas that is lighter than air. And, apparently, ribs tend to float even if the tubes are empty, as if they weren't really needed.

As an example, take a 5m+ rib with alu hull. If you then, theoretically, removed the tubes and just extended the alu hull to compensate, what difference would it make? Compared to a similar sized 'traditional' boat with a similar glass fiber/grp/alu v-shaped hull.


Only reason I could find after reading though tons of general information, is that they are a "shock absorber" when you bump into other boats.... That can't surely be the only reason to carry around complicated pressurized tubes that needs careful special maintenance.

Can someone explain this to an uninitiated and uneducated idiot?

over the years there have been many like you with such questions and to be honest i feel it to be a waste of my time to explain to you all. So why don't you do your homework by doing a search in the forum then contact one of many rib seasafari companies which operate in Sweden and book your self a nice day cruise preferably when the sea is not flat. If after that cruise you will not see the advantages of a rib then best start looking for a new hobby. If you however learn anything from that trip then kit would be nice if you could share your experience with the forum.

[RoyP]

[breezeblock]

I went for a rib as I am shit at driving and would probably sink a hard boat

[GuyC]

Originally Posted by udihow

Lately I've been searching a lot on google, looking through every relevant web page I could find but there doesn't seem to be any simple answer. There must be something I'm missing.

More specifically; what function do the tubes really have?

I get it that they offer buoyancy on smaller ribs. But with larger ones where tubes barely touch the water or often not at all, they cant possibly offer any flotation or stabilization? Unless they are filled with gas that is lighter than air. And, apparently, ribs tend to float even if the tubes are empty, as if they weren't really needed.

As an example, take a 5m+ rib with alu hull. If you then, theoretically, removed the tubes and just extended the alu hull to compensate, what difference would it make? Compared to a similar sized 'traditional' boat with a similar glass fiber/grp/alu v-shaped hull.


Only reason I could find after reading though tons of general information, is that they are a "shock absorber" when you bump into other boats.... That can't surely be the only reason to carry around complicated pressurized tubes that needs careful special maintenance.

Can someone explain this to an uninitiated and uneducated idiot?

The shock absorber bit is true but it isn't the bumping into boats that is the prime reason for the tubes, it is for softening wave impacts. The tubes deform and absorb some of the wave energy making it a more comfortable ride.

The tubes add buoyancy. Whilst a larger RIB would still float without the tubes, the converse is also true. The RIB will remain afloat and stable even when the rigid hull is entirely flooded. If you suffer hull damage in a hard boat, it is probable that it will sink as there will be little in way of watertight integrity. If it doesn't sink, its stability will be severely compromised. In a RIB, and as long as a number of the tube compartments remain intact, it will remain afloat and it will remain stable.

[HDAV]

Time for a history lesson.....

Atlantic College students' RIB sea safety revolution http://www.bbc.co.uk/news/uk-wales-s...wales-13377377

[gtflash]

classic post on here or boatmad from Jon Fuller. Excluding all the ranting it convinced me it is the hull that softens the ride, not the tubes. Ive also been on some awful riding ribs and great riding hard boats. 2psi of tube pressure v's the sea at 40mph?

That said i love a rib, more to keep you afloat, soft to sit, stand or crash into things with.

[Maximus]

Knob.

[ShinyShoe]

Some people think you are trolling. I'm going to assume you are not and try to answer this respectably.

Originally Posted by udihow

what function do the tubes really have?

I get it that they offer buoyancy on smaller ribs. But with larger ones where tubes barely touch the water or often not at all, they cant possibly offer any flotation or stabilization?

Except on some exceptionally large RIBs 11m+ the tubes will at some stage be touching water. Possibly not in a straight line but hit a wave, take a high speed tight turn and the inside side of the curve tends to dip down and will then contact water. So you gain manoeuvrability without loosing stability.

If you need to bring things in over the side (people?) You can put three or four people on the tube and the boat remains stable. You can make the freeboard higher on a hard hull to do that but may not get as much stability (capsizing a rib in anything other than surf is almost unheard of) increasing freeboard in an attempt to achieve the same makes the height to lift from the water harder.

ribs tend to float even if the tubes are empty, as if they weren't really needed.

Yes but. You wouldn't drive one at 40kts with no tubes and expect to get away with it.

As an example, take a 5m+ rib with alu hull. If you then, theoretically, removed the tubes and just extended the alu hull to compensate, what difference would it make? Compared to a similar sized 'traditional' boat with a similar glass fiber/grp/alu v-shaped hull.

not sure I follow the comparison. Take a landrover, remove it's off road tyres, fit some mini 13inch wheels and say it's no better than a city car. ...

Only reason I could find after reading though tons of general information, is that they are a "shock absorber" when you bump into other boats....

Look at who uses them most:

• Lifeboats (1,2,3)
• Divers (3,4,5,6,7)
• Sailing club safety boats (1,2,3,5,6,7)
• Harbour masters (1,5,6,?7)
• Law enforcement(1,2,3,4,5,6,7)
• Hardy distance cruisers who want a challenge(2,4)
• Beach goers with Ringo's etc(2,3,4,7)

1. Tend to come alongside other boats in sometimes difficult conditions where fendering is helpful
2. Tend to perform high speed turns where stability may be helpful
3. Tend to pull people over side where padding may help and stability helpful
4. Tend to tow distances where lighter hull may save money
5. Tend to sit 'still' on water for periods of time where stability may be helpful
6. Tend to want open deck space for transportion of goods or casualties
7. Tend to transport groups of people (short) distances where a soft tube is not considered an uncomfortable seat (a typical 5m Rib is rated 8+ pax, a 5m rigid boat may not be)


There are people on here with 'hard tubes' (polyethylene hulls with polyethylene tubes but still air filled). They achieve 80% of what a rib does, compared to 65% of what a traditional hard boat does. But on the whole traditional hard boats tend to be more likely to have some form of cuddy so offer more shelter. Shelter might be a defining requirement for a line fisherman, but may be a hinderence to moving around on a small boat for people needing to do lots of movement...

The best way to compare this is to say 'do I need a 4x4 car' or 'do I need a luxury car for the motorway'

Most people make some compromise on their car. Most people make compromise on their boat.

[beamishken]

Has Bigplumbs sneaked back in [emoji1787][emoji1787][emoji1787]

[Nasher]

Stability at rest and the ease of recovery from the water are my reasons for having a RIB, but mine is actually used as a diving support boat at times.

However, all Boatmad types know that we Ribnet types go everywhere whatever the weather, fully prepared, and tooled up to the hilt.

I personally grip the Bowie Knife held between my teeth harder knowing that if I let go it might puncture a tube.

Nasher.

[jeffstevens763@g]

With the power of the internet I makes me wonder sometimes on here why these questions are asked

[SixtyNorth]

The tubes provide a lot of reserve buoyancy which is very useful. For example, if the boat gets swamped by a breaking wave. If you compare the loads that RIBs (and inflatables) can carry compared to similar size traditional boats you will see another benefit. One more... they can be lighter to tow than a similar sized GRP boat.

[GuyC]

Originally Posted by jeffstevens763@g

With the power of the internet I makes me wonder sometimes on here why these questions are asked

I agree but

a) it is his first post so I'm happy to cut him some slack;

b) you could apply the same thinking to almost any question on any subject.

[HDAV]

Originally Posted by GuyC

b) you could apply the same thinking to almost any question on any subject.

You could but you shouldn’t......and reading the internet is an increasingly pointless exercise as unlike traditional media there are basically zero controls (not that traditional media is perfect by any means)

But the amount of just wrong, misleading, fake and sales spiel is incredible.

The question may be pure trolling......but one person asked 500 read the answers.....100 will believe them , 100 disagree with them, 100 forget they ever saw them and 200 were bots which will do god knows what with the answers....

Simplest answer is why not.........why blondes, brunette, redheads and bald?

[jeffstevens763@g]

Originally Posted by GuyC

I agree but

a) it is his first post so I'm happy to cut him some slack;

b) you could apply the same thinking to almost any question on any subject.

Not being hard but under his own admission an uneducated person now just typing history of ribs would answer his question and educate him

[Highland Haggis]

Some people can't be educated Jeff [emoji23][emoji23][emoji23][emoji23]

[HDAV]

Originally Posted by Highland Haggis

Some people can't be educated Jeff [emoji23][emoji23][emoji23][emoji23]

Is it here or another forum where one member has the signature.

“You can’t educate prok”

[Pikey Dave]

Originally Posted by HDAV

Is it here or another forum where one member has the signature.



“You can’t educate prok”

Ahem, cough cough!

[MatFromPoland]

For me bouyance and stability. Can't find (or hard to find) 5,4m GRP boat dedicated for 7-9 people. I was able to drive so many in mine RIB on seats (in Greece you can't sit on tubes when boat uses engines to move).

And ... the same for girls (sorry cars) - sometimes you can't aswer why you like this type ... If I go for 7m with many seats - again it be RIB