Discussion of HP required to move sailboats....

[s/v Faith]

It seems like the trend is for more recommended HP than in the past. I recently read a recommendation for about 3 HP for every 1000 pounds displacement......

  Wow, that is overkill.  Maybe for a multihull, or a motorsailor... but not for a regular displacement hull.

[maxiSwede]

I feel like those people are truly missing something. I was told once- anybody can sail in 10- 15, takes a REAL sailor to sail in 2-3. :D

That's a good point taken.  ;D

[Amgine]

I rather think that refusing to have an auxiliary motor aboard is an admission of weak-mindedness, for there is no need to use it except in times of emergency; but I know perfectly well that if I had one I would seldom attempt to enter or leave harbour without its assistance, to the ruination of such seamanship as I may have acquired. I once believed that the solution of that problem would be to have an engine of such low power that it would be useless in anything except a calm; but that will not do for it is then useless in a swell also, and the sea is seldom smooth.

...

The internal combustion engine ... allows the owner who has but limited time to get much farther afield with the certainty of being able to return when he wants to, and it has opened up some of the more difficult creeks and anchorages which he might not have attempted to reach under sail alone.

In my very limited experiences, almost solely aboard boats with very small inboard diesels (the smallest being a lovely Lister AC1W, which survived sinkings and groundings and never failed to start for me) having enough horse power to move the specific boat at hull speed in calm water is enough. Somewhere between 1.5 and 2x that much gives great confidence when setting a hook, or pushing into a steep wet chop. More than this has little noticeable effect on either confidence or speed through the water, but does seem to cost more than the multiplier to run per hour. (Perhaps because when motoring I tend to push more rpms than beneficially turn into speed.)

The one boat I've owned which had an outboard, in a well, I swore at more often than not, and the outboards and I never got along well.