• PM_Your_Nudes_Please@lemmy.worldEnglish
      6·
      3 months ago

      “Fixed” refers to the fact that the keel isn’t removable. It’s either part of the boat’s hull, or it’s bolted on and can’t be removed without dry-docking the boat.

      There are some boat designs with removable keels. For instance, many small sailboats (called a dinghy) have removable keels, so you can remove the keel and beach them easily. The downside to having a removable keel on a sailboat is that it makes the boat prone to capsizing in strong winds; A fixed keel can have a built in ballast to keep the boat from tipping. But on a dinghy, you need to use a live ballast (literally your own body weight leaning out of the boat) to counteract the wind’s effects.

      • riodoro1@lemmy.worldEnglish
        2·
        3 months ago

        Isn’t a non weighted and removable „keel” on small sailing dinghies called a „dagger board” and is there only for mitigating drift?

  • grue@lemmy.worldEnglish
    17·
    3 months ago

    One neat unmentioned advantage of a bilge keel is that it often enables careening without having to tip the boat on its side or use stands to prop it up.

    I also feel like this cool guide should mention differences in draft between different styles of keel.

  • Ersatz86@lemmy.worldEnglish
    17·
    3 months ago

    The first entry “full or long fin keel” is technically a modified full keel with a cutaway forefoot. A true full keel would have the keel extending almost in a straight vertical line from the stem to intersect the horizontal line of the bottom of the keel.

    The modified full keel is a nice compromise between the comfort and stability of a full keel and the maneuverability of a fin keel.

    Both types of full keel benefit from having a fully protected propeller in an aperture and the additional safety and security of a fully hung rudder. Additionally, nothing beats a full keel for rock solid dependability as the keel is molded into the hull, whereas a fin keel is generally attached by bolts, a far less structurally reliable method.

    Neither can compete for speed or maneuverability with a fin or bulb keel for several reasons, not the least of which is far more additional wetted hull area and the water friction inherent therein.

    I could be mistaken, but I believe this is the first time I’ve ever seen “full” and “fin” used to describe the same item. I believe those are mutually exclusive terms.

      • Ersatz86@lemmy.worldEnglish
        5·
        3 months ago

        Lol, in that case, I regret for once not divulging the unsolicited full info dump for fear of growing preachy/pedantic. We might’ve achieved full arousal!

  • henfredemars@infosec.pubEnglish
    4·
    3 months ago

    Does having a keel imply that the ship is self-righting? Like, completely submerged, does it also guarantee that the ship floats back to the top, oriented?

    • electric_nan@lemmy.mlEnglish
      3·
      3 months ago

      Yes. They are weighted with lead, and help keep the boat topside-up. They are also a critical component to the functioning of sail propulsion. The keel works in a kind of opposition to the sail to propel the boat forward, similar to how squeezing an ice cube between your thumb and finger will ‘squirt’ it out in a direction perpendicular to those forces.

    • noughtnaut@lemmy.worldEnglish
      1·
      3 months ago

      But also no, if it’s capsized, the boat may right itself in time before it floods to a point where it sinks.

      A fully submerged boat will not bob to the surface. The keel adds stability and (counter)weight, but negative buoyancy - what keeps the boat afloat is the air in the hull.

      Once it’s fully submerged, there’s nothing pulling it up (unless you have some seriously good (and closed!) hatches…