Does a catamaran plane?

I remember them, vaguely. Last one I tried had a two stroke motor... ?!

 

A boat is planing when water breaks free from the transom, the transom is, basically, above the water.

 

He-he Meanz... you struck a cord here. Even Masalai posted longer than the usual 2 or 3 lines... I was shocked

Typical engineers... first things are all kinds of formulas and names calling to justify arguments. Even freud (the bloody sexist's) name came up

The answer to Meanz's Q was simple, yes or no

I guess it depends what you want. A planing boat is going to suck at low speeds. A displacement hull is going to suck at high speeds.

The Q should rather be, do you want to go fast or slow.

Fast - go for the planing. but it's going to suck at low speeds.
Slow - great for cruising. You may not get it on the plane unless there's a hurricane.

There is a compromise though. If you do go for the displacement hull, you can have all the advantages of a nice cruiser. If you want to go fast, start up the two 300 VMax Yammies and let rip. Sure you'll plane, no question about it. Just remember to reef the sails first though

 

I had the priviledge of sailing an older Australian designed off the beach cat called an Arrow cat. Raced it for about 6 years.
The design from the seventies was flat bottomed with moderate rocker. 1/8 " ply construction 14' long 6' wide and only weighed 130 lb rigged. Two sail, one man on trapeze.
One two occasions the cat planned.
This was in flat water and solid breeze on a reach. It "broke out" with my weight well back on trapeze and was definitely planning, typified by bow up not down attitude with less then half of the leeway hull in contact with the water and the boat speed was considerably higher that the normal reaching peak, i guese it at in the low 20's as opposed to around 15 knots. Anyone who has sailed a 14' skiff will know about planning.
I have also been on two different trailer yachts that have planned , both had little rocker and big fat bums, light hull weight and big winds.
I think it unlikely that a cruising cat would plan, two little water plan for the power/weight. But it doesn't matter they go well enough in displacement mode, I have seen a steady 15.5 knots on gps on my 38' bridgedeck cruising cat and peaked at 17.8 ,NOT swell assisted. That's fast enough for my home on water.

Cheers Bryan