Home grown Laser Hydrofoils

Discussion in 'Sailboats' started by Kevin Charles Rissell, Aug 1, 2019.

  1. Kevin Charles Rissell
    Joined: Aug 2019
    Posts: 16
    Likes: 6, Points: 3
    Location: Oakland, MD, USA

    Kevin Charles Rissell Junior Member

    It sails fine when not foiling, though not quite the same as a standard Laser. The foils having much less cord makes the sideslip more noticeable in low wind/low speed conditions noticeable.

    Tacking requires more ‘authority’. In other words you have to tack hard and quick to have enough momentum to avoid getting in irons at the end of the tack. It seems counter intuitive, but because of the increase in sideslip, a smooth arcing tack loses more momentum throughout the tack than shoving it over hard.

    For ver. 2.0 I intend to increase the cord of the rudder by 2 inches, and the cord of the daggerboard by 4 inches, roughly.

    Finally, there’s very little ‘underside anchor’ effect, and once you’re up to speed, most points of sail seem just as fast as a standard Laser. Sideslip affects the acceleration though, so getting up to speed takes longer, and beats and very close reaches are definitely a struggle to keep your speed up on. Definitely slower on those points of sail.

    Honestly, I was pleasantly surprised at the lack of ‘underside anchor’ effect. I really expected it to be a very large obstacle to successful foiling.
     
  2. J Smythe
    Joined: Jul 2019
    Posts: 20
    Likes: 3, Points: 3
    Location: USA

    J Smythe Junior Member

    That's great. Imagine taking that baby for a ride not knowing some madman had put foils on it, and the shock on your face when you start to "magically" float for some reason.....before eating it in the drink due to not realizing what was happening.
     
  3. Kevin Charles Rissell
    Joined: Aug 2019
    Posts: 16
    Likes: 6, Points: 3
    Location: Oakland, MD, USA

    Kevin Charles Rissell Junior Member

    I can imagine, and in fact have done almost exactly that.

    The first time it started to fly, I was frozen with surprise, excitement, and considerable anxiety about not knowing what exactly I should be doing, if anything, now that the foils were actually doing what they were made to do.

    Being frozen in place meant I didn’t shift my weight. Consequently, the increasing take-off angle of attack, due to the frozen, aft-weighting and completely overwhelmed designer, overcame any input from the wand to reduce lift, the main foil broke the surface of the water and immediately losing all lift resulting in the Laser landing back on the water hard and with a pronounced bow-down attitude.

    In other words, it porpoised badly and crashed down hard, taking about 3 inches of water over the deck....

    I was amazed that I wasn’t flung off, and how easy it was, under the right circumstances, to completely fill the foot-well in one swift motion....

    Still, you couldn’t have wiped the smile off my face with an angle grinder.
     
  4. J Smythe
    Joined: Jul 2019
    Posts: 20
    Likes: 3, Points: 3
    Location: USA

    J Smythe Junior Member

    You've got to figure out a way to be able to have it in the water for friends that don't know about it, and then take them for a ride and see what happens when you start flying.
     

  5. Kevin Charles Rissell
    Joined: Aug 2019
    Posts: 16
    Likes: 6, Points: 3
    Location: Oakland, MD, USA

    Kevin Charles Rissell Junior Member

    That would be interesting, though the white gap seals on the foils are kinda hard to hide even in murky lake water.
     
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