Planing Dinghy: Hp vs Dinghy type vs #Passengers

[Jon Hacking]

Originally Posted by Jammer

The life-cycle cost of having a 3.1m RIB+15hp outboard is large...

Jammer, this thread is an attempt to correlate dinghy length, type, & engine with planing ability. It's not really a place to justify your choice not to have a planing dinghy.

We've cruised for almost 30 years, including 7 in the eastern Caribbean, & we've never had a dinghy or an engine stolen. Your claim of needing to replace a dinghy every few years is gross exaggeration (possibly to justify your own decisions?)

Our alloy RIBs with outboards cost ~$5K in both 2001 & 2016 (bigger dinghy & bigger dollars in 2001). Our first lasted 15 years of pretty hard work, with little additional cost, & we sold it for $1,000, so it cost us about $280/yr. Our current alloy RIB is now 5 years old & has needed to be patched (which I did myself, with epoxy) but is otherwise in excellent condition.

We each make our own cruising decisions. Your Hunter 26 can't carry much dinghy, while our cat has built-in davits strong enough for us to leave our 25hp engine on while sailing.

But trying to put down other folks from using planing dinghies (on a thread specifically looking at planing dinghies) just because you choose not to have one isn't being helpful or supportive of the cruising community.

[chrisr]

Originally Posted by Jammer

The life-cycle cost of having a 3.1m RIB+15hp outboard is large. Theft is a huge problem. I didn't write down a source but in my notes is a comment that the average full-time cruiser has an outboard stolen once every two years; most of the time the RIB goes with it.

i beg to differ.

we are full time live aboard cruisers and we have never had a dinghy or motor stolen, nor do we know of anyone who has had a dinghy or motor stolen. very few of us even lock our dinghies up (unless being left overnight)

if this level of theft is your experience, i suggest you move somewhere else. it's certainly not that common a problem

cheers,

[chasfgr]

IMHO, if you can't remove the OB from the dinghy, when anchored, you have an insuperable problem, that you have to tow it evrywhere.
I found the biggest engine I could handle was a 4hp, on a 2.7m rigid hull.
This would just plane with one up and allowed carriage of 3 with luggage, safely.
It also fitted, over the forehatch, on deck, for longer trips, deflated if you needed to for sail handling.
My original setup was a 2hp on a soft-bottom Avon Redstart. Impossible to row,intended for paddling, and risky returning from a run ashore.

[wingssail]

Originally Posted by Jammer

The life-cycle cost of having a 3.1m RIB+15hp outboard is large. Theft is a huge problem...

Theft is a problem, I've heard of several. But in 35 years we've never had a dingy or motor stolen.

We haul our dingy each night (with spin halyard, takes three minutes) and drop it each day to use, (takes 30 seconds). The bridle is wire, you don't chop it with a machete.

The dingy is 12 years old and the motor 21 years old, total cost when new: $4700. Cost per year=$305 and counting.

We will always have a planing dingy, as large as we can fit on the boat, and no davits, ever.

[valhalla360]

Dux Hammerhead 13ft w/ 40hp outboard.

No problem planing up to around 600lb cargo. Beyond that about 10kts displacement speed (plenty of power but the hull shape has difficulty developing the initial lift with 6-8 passengers).

Top end planing around 60mph.

https://duxboats.com/product/dux-ham...d-model-pd-400

[Jammer]

Originally Posted by Jon Hacking

Jammer, this thread is an attempt to correlate dinghy length, type, & engine with planing ability. It's not really a place to justify your choice not to have a planing dinghy.

Adelie (who wrote the opening post) asked specifically about lower cost options upthread. Who are you, the thread police?

We each make our own cruising decisions. Your Hunter 26 can't carry much dinghy, while our cat has built-in davits strong enough for us to leave our 25hp engine on while sailing.

My Hunter 26 is for sale because I am purchasing something larger. This isn't about my Hunter 26 and what works for it. (If it were, my answer would be that there isn't really a usable dinghy that works on it, it can carry an 8' dinghy on the foredeck which isn't large enough, or various inflatable options that fully collapse for storage below decks)

But trying to put down other folks from using planing dinghies (on a thread specifically looking at planing dinghies) just because you choose not to have one isn't being helpful or supportive of the cruising community.

Sensitive, much? I didn't put down anyone's choices. Sail what you want. Use whatever dinghy you want. Adelie says he's doing research on lower-cost entry level alternatives, and a large cat with davits that can carry a rib and 25 hp motor isn't a lower-cost entry level alternative.

[MicHughV]

My first "cruise" was to the B'mas....most waterfront bars or towns have a "dinghy dock" to which could be tied umpteen dinks. Patrons often had to clamber over other dinks to get to theirs, often in an inebriated state, at night.....in the 6 months or so that I was there, never saw, heard or knew of anyone that had their dink stolen or otherwise messed with.
When I first got there, dink security was on my mind, especially at night. I was quite paranoid about leaving my dink unattended. This lasted about 2 weeks.

[Lazerbrains]

I currently have a 10'4" Avon rib - it's a heavy one at 154 lbs. With an 8hp 2 stroke with hydrofoils, it would easily plane one person (200lbs), but not two no matter how we tried. I switched to a 15hp 2 stroke and now easily planes with three people, 6 gallons of fuel, and supplies.

I used to have a Saturn Kaboat, very narrow iwith nflatable floor - could easily plane with a 3.5hp and was the easiest rowing dinghy I have ever owned. But the sun was not too kind to the PVC, so traded for the hypalon RIB. If they ever make the Kaboat out of hypalon I will buy one again.

[Cheechako]

Well, IF a dingy DOES get up on plane, we don't know how much of our HP it took!

From experience I can tell you:
-Weight of the dingy and load is the biggest factor.
-A heavy double floor 10+ ft Rib (~135# dry) with a 15 hp 2 stroke Yamaha would get up readily with two small people.
-A single floor 9 ft single floor RIB was overpowered with the same engine and very squirrely to control. More the shorter length than the 35# less weight I think.
-A 9 ft air floor light dingy would plane just barely with a 5 HP Merc and two small people. You had to help it get up on plane but then it moved well.
-A 10 ft Achilles plywood floor would plane readily and fine with an old Johnson 9.9 HP.
-The same Achilles would plane with a 4 hp Merc and one small person. Barely.... if you are lucky.

[wkearney99]

We've got an Avon R310 RIB with a Yamaha 15hp and it barely gets on plane with one person. Granted, I'm a big guy. With my kid with me it'll require both of us moving well forward and waiting a while before it pops up on plane. But even then it's a wild ride where one wrong move with the tiller will fling your ass overboard.

I'm looking to upgrade and considering a Highfield CL360 or AB 11ALX with a 30hp.

[Adelie]

Update new posts here and info from 2 more threads I found.
Not included was a KaBoat that would plane with 3.5hp but no indication of how many people. The KaBoats look interesting because are probably one of the few inflatables that row well.

[chris mac]

Originally Posted by chris mac

We had a highfield rib 2.9m with a 15 hp Yamaha 2 stroke. With 1 person it jumped up and planed almost instantly. 2 people took a while and we had to shift forward to get on plane. 3 people, no chance of plane.
We just bought an achilles rib 3.1m. Same outboard. With 1 person it catwalks and takes a few seconds to get the nose down and planing. With 2 people it gets on plane almost instantly. We have yet to try with more people or extra weight.
The weights are almost identical, The achilles is the ul version. so the extra length has made a significant difference.

Just adding new info as we have used the new 3.1 m Achilles more.
With 3 adults(roughly 550 lbs) it gets on plane fairly easily.
Same 3 adults plus additional 100lbs of gear in the bow, it did get on plane but struggled. I believe it would get up with 4 adults shifting weight as needed.

[Jon Hacking]

Originally Posted by chris mac
We had a highfield rib 2.9m with a 15 hp Yamaha 2 stroke. With 1 person it jumped up and planed almost instantly. 2 people took a while and we had to shift forward to get on plane. 3 people, no chance of plane.

Chris Mac, you should REALLY try fins on your 15. They're amazing.

After the kids left we downsized. We now have a:
Highfield alloy 2.9m RIB, 15hp Merc 2-stroke, 4 adults

When we first bought it, it would struggle to get up even just with 3, & with 4 we all had to crowd forward & it would take a long time (& they better be smaller adults). Then we added a pair of Duol-Fins to the motor. These are fabulous! It now jumps on the plane, & it stays flat while it does so. No more crowding forward unless we're 4-up.

[sailhand]

12 foot catamaran hard dinghy. 50kg boat 3.5hp four stroke tohatsu 2 large people 220kg total or three average people around same total planes easily at 9 to 10 knots. Rows really fast.

[Macdoug]

We have a high field 2.8 metre with an inflatable floor. 5hp two stroke. It just gets on the plane with two adults (up to around 160kg total weight), but it takes time and weight distribution to hit the plane.