Discussion Ship's inertia

[smrtwhkd]

Maybe it's just me. Somehow I feel the modeling of ship's inertia is a bit inadequate. If you go directly against the wind, the deceleration is very rapid. I had a few experiences on board of a sailing ship. It feels that it takes a while for a ship's speed to go down to zero. It will slow down gradually, but not down to nil in a matter of seconds. Also, heavier ships can glide on even longer than lighter ships. It's my feeling, but I am not an sailing ship expert.

 

[Pieter Boelen]

@smrtwhkd: Which game mode are you on? Realistic or Arcade?
Or did you start a New Game on one of them; then switch to the other?

I had a few experiences on board of a sailing ship. [...] It's my feeling, but I am not an sailing ship expert.

That makes you more of an expert than I am.

 

[Grey Roger]

Also, @smrtwhkd: what sort of ship are you sailing in PoTC? If it has a lot of square sails, they're going to actively push you backwards when you turn against the wind. Try furling all sails before turning.

Modern sailing ships tend to have sharp bows, whereas the ships you're sailing in PoTC have rounded bows. The real ship on which you were sailing therefore probably had less drag than anything you'll be sailing in the game. (And it might also have been using an engine when the wind was against it. )

 

[Pieter Boelen]

Modern sailing ships tend to have sharp bows, whereas the ships you're sailing in PoTC have rounded bows.

Very fair point.

The real ship on which you were sailing therefore probably had less drag than anything you'll be sailing in the game.

That I wonder about.
Less streamlined hull with a heavy hulk; wouldn't that slow down faster?
Even on sheer friction?
Or would it be the opposite because the large mass would keep going longer?

And it might also have been using an engine when the wind was against it.

Heh; true.
They do that.

 

[Grey Roger]

That I wonder about.
Less streamlined hull with a heavy hulk; wouldn't that slow down faster?
Even on sheer friction?

So a less streamlined hull with a heavy hulk, such as a ship in PoTC, would stop almost at once; while a ship with a more streamlined hull, such as a modern real-life sailing ship, would slow down gradually.

 

[Pieter Boelen]

So a less streamlined hull with a heavy hulk, such as a ship in PoTC, would stop almost at once; while a ship with a more streamlined hull, such as a modern real-life sailing ship, would slow down gradually.

You would say so...
Wouldn't you?

Then why am I so confused?
Maybe it's because there's several factors that play with/against each other?
- Streamline of the hull
- Weight of the hull
- Wind drag of the superstructure, rigging and sails

Difficult to compare a galleon with a clipper, because not just the hull shape is different; but so is the weight.

I think, the heavier a ship (regardless of streamlining), the longer she'll take to change speed.
Which is why my own Atlantis is very forgiving to being mishandled in tacking.
She's almost twice the weight as certain similarly sized sailboats; so even if you mess up, you won't immediately be dead in the water.
And with the hull still shaped quite well and maximum speed a factor of waterline length, she isn't actually all that much slower as similarly sized sailboats.
My old Holland America LIne boss expected to sail circles around me... but the difference was FAR less than he thought it would be.
(He's got a sliiightly shorter but much more racerly-tailored sailboat almost right next to me in the marina.)

 

[smrtwhkd]

So a less streamlined hull with a heavy hulk, such as a ship in PoTC, would stop almost at once; while a ship with a more streamlined hull, such as a modern real-life sailing ship, would slow down gradually.

That can't be in the real life. If that's the case then you can't really tack into the wind. In order to tack into the wind, a ship needs inertia. If it stops almost at once then you won't have residue speed to tack across the wind to the other side.

 

[Grey Roger]

Indeed, tacking into the wind relies on inertia. It also relies on either having a fore-and-aft rig such as the sloop or xebec in the game, or furling all sails before making the turn. If you do that, so that the sails aren't actively decelerating your ship as you turn, you can turn a square-rigged ship such as a galleon across the wind and not lose all speed.