how fast do outboards go?

[Boatlover]

Hi Guys,

I am new here

I am very glad that i found these forums

I got some questions that i hope you can please answer

If i want to move 10 people in an inflatable or RIB then how many HP outboard would i need? I want to move at maximum 15 MPH.

I heard you can now get electric powered outboards, are they any good, fast?

One other thing, with a RIB do you inflate them yourself? Or is that only with inflatables.

You know in whitewater rafting are those boats inflatables or RIBS?

Really, i only want either of these boats for moving in calm water, up and down a bay, probably max 30 miles each way.

If you can please get back to me with some answers, sorry if i asked a lot,

any help much appreciated

Many many thanks

[Nos4r2]

What exactly do you want to do with the boat? Where and why?

[willk]

Originally Posted by Nos4r2

What exactly do you want to do with the boat? Where and why?

or,

Hello Boatlover!

A first post is always a brave step! Your's asks a lot of questions and we'll (always!) have a lot of answers, often condradictory.... If you give us some idea what you're planning to do, we'll have more to go on. 30 miles is a fair lick in any craft. Many will be itching to inform you that RIBS/Inflatables have nothing in common with whitewater rafts, and they don't, despite superficial similarities (tubes). Let us know!

[Boatlover]

Hi

Many thanks for your replies guys

I am looking to just cruise a long the coast line, to be about no more than a quarter of a mile out from the shore. To go fifteen miles in one way and then refuel and come back another fifteen miles. I only want to go fifteen miles per hour and doubt i would be using it to pull a waterskier or wakeboarder. I would like to carry mainly five people on it, but some times would be taking 6, 8 or 10 people in total on board the boat. I would as well take some snorkel gear and a picnic box. The weight shouldn't be too much of an issue as i won't be carrying oxygen tanks for scuba diving as i'm only a snorkeler.

What can you suggest

Many thanks

[Polwart]

to get us started on the answers.

• outboards typically rotate at around 5000-6000 rpm
• the gear box ratio is typically somewhere beteeen 1.8-2.5 ish
• assuming the engine has sufficient power the top speed is then defined by the pitch of the propellor

most ribs (or sibs suitable for the people you want to put on it) will only start to plane [lift out the water] at 10-15 mph. Below that speed a rib may not be your best choice,

[karlT]

Welcome to rib.net

I think from your questions that maybe you should consider a level 1 or even a level 2 course before you even venture 100 yards from the shore. Speak to a school before booking the course and discuss the boats you may use on the course. They will cover the merits of many types of craft that may be suited to your needs.

The level 1 course will introduce you to a variety of topics you may have never thought of and will improve your chances of staying alive, not having to call the lifeboat, knowing how to declare an emergency and MOST IMPORTANTLY YOUR & YOUR FAMILIES ENJOYMENT!!!!

FYI divers don't generally use Oxygen tanks as it is poisonous at only a shallow depth

Good luck and happy boating

[willk]

Yup, that sounds like a nice way to spend an afternoon!

Any small RIB/Inflatable of around 5 metres or slightly smaller will cruise 5 up, with the minimal kit you list. 30 miles is fairly "do-able". I'm guessing, but a 50hp outboard should suffice to plane (ride over the water) at 15-20 miles an hour. 10 up is another matter and would require a larger craft of about 5.8m or more. Again, a disproportionately larger engine of perhaps 75 - 90hp would be needed, probably not worth your while?

Whatever kit you need, experience or training is even more important. The trip you mention is not a paddle in the kiddies pond. We can drown in 5 feet of water and proximity to the shore is not always a help - it's the thing we tend to wreck our boats on!

Best of luck with the plan!

[Polwart]

I would agree with Karl - a course will widen your boating choices up and let you decide what you need (200 quid on a course is better that wasting money on the wrong boat, and you will be less likely to damage the boat or yourself). If you only want to do 15 kts then probably a rib is not what you want/need.

It might hurt a few people here to say it - but a "hard boat" may be better suited. Either way a boat which can confortably sit 10 will be quite big for a first boat.

[willk]

Originally Posted by karlT

FYI divers don't generally use Oxygen tanks as it is poisonous at only a shallow depth

Bang on, but as the Press often insist on calling them just that, what hope the rest of the mere mortals?

[Pete7]

Originally Posted by willk

Bang on, but as the Press often insist on calling them just that, what hope the rest of the mere mortals?

Along with the other classics:

Bottles - something milk normally comes in.

Tanks - Used by Armies to keep troublesome civilians in check

Flippers - Name given to Dolphins

Pete