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Home Forums Community IRL GTGs Ephemerisle

This topic contains 6 replies, has 5 voices, and was last updated by Profile photo of SailorTrash SailorTrash 6 years, 6 months ago.

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    Profile photo of Patri

    We’re hoping to do the first Ephemerisle, a true offshore conference, in the summer of 2009, and bring Coaststead to it.

    Profile photo of Patri

    I’m thinking about having one of the conference workshop topics being to start planning Ephemerisle.

    Profile photo of SPyle

    Ah, only if I could actually attend. Not owning a boat, and being a poor student living in the UK don’t help. 😛

    I wish the best to you and really do hope it’s a great success.

    Profile photo of

    The choice of how the Ephemerisle is controlled will affect where it can happen and how boats/structures can be connected.
    Anchoring is a well understood approach that works well under some common conditions.
    One important disadvantage is that beyond some fairly shallow depth, standard equipment that comes with most boats won’t work. The anchor line often needs to be 7 times the water depth. Wind, waves, and characteristics of the bottom also affect how well anchors work. If every boat needs to find an unusually long anchor line, that’s going to reduce the number of people willing to attend.
    Having many boats connected to one anchor would presumably work, but it requires a larger than normal anchor (the typical boat anchor is chosen to handle one boat, and even then it sometimes doesn’t hold in the first spot you try).
    Having many connected boats each rely on their own anchor may have problems when the wind shifts. My recollection is that that isn’t important for 3 or 4 boats. I don’t know what happens with larger clusters.
    Mykolaj suggests running engines continuously on a few boats (presumably on the windward edge of a cluster). I have doubts about whether I’d trust typical boat engines to behave properly when everyone’s asleep. That’s assuming the engines will be quiet enough for people to sleep. I definitely wouldn’t enjoy trying to sleep near one. Could there be quiet, low power motors that would be more appropriate than standard ones? Even if there are, they’re unlikely to keep the boats in a fixed location without frequent supervision, as changes in the wind will alter the desired force.

    The approaches I consider most promising involve a combination of modest drifting and occasional use of engines.
    I assume Ephemerisle will be located where currents are weak, so that wind will cause most drift. If the wind turns out to be too light to be the dominant cause of drift, I expect we’ll have fewer problems than with strong winds.
    I imagine that we would drift most of the time, and about twice per day we would coordinate a powered upwind move.
    I’ll assume that we will prepare for winds up to about 25 knots, and will cancel the event if the wind is stronger (which is fairly rare in summer in California). I’d guess that would produce a maximum drift of 2 to 3 knots, which will move us more than we want if we’re trying to stay a few miles from shore, but would be less important if we’re aiming for 12+ miles. With normal daily fluctuations in wind speed, it’s unlikely that the average would be more than half the maximum.
    Sea anchors sound effective at slowing the drift, and may also provide a small force to help keep boats separated if the windward boats have larger sea anchors than the others. Presumably we’d want something else to keep boats apart when the wind is calm.
    If Ephemerisle is in the San Francisco Bay, the maximum distance we can safely drift before reaching land or a shipping lane appears to be about 5 miles. I’ll assume we hope to be able to drift unguided between about dusk and breakfast (10 to 12 hours?). That implies limiting our drift to about 0.3 or 0.4 knots, implying that we hope the sea anchors can slow the drift by a factor of 5 to 10. I haven’t been able to find good data confirming that this is possible, but the information I have found suggests we can at least come close.
    If Ephemerisle is a few miles from the southern California coast, we have more options and can probably pick an area where we can safely drift more than 5 miles. Possibly near Long Beach (near the Queen Mary, and the flight of the Spruce Goose). With the common WNW winds, we might be within 20 to 30 degrees of paralleling the coast that extends to the southeast. There’s no obvious way to handle Santa Ana winds, but they appear rare in July.
    Since we won’t be able to precisely calculate the drift rate in advance, we’ll need to observe it (with a gps?) once everything is connected. This may mean that it will be hard to allow late arrivals to connect, since that might increase the drift rate. In addition, we would need to research whether the drift is a linear function of the wind (I suspect not).

    Profile photo of

    I would recommend a floating breakwater to surround the boats or platforms. The open ocean is probably otherwise too unfriendly to a collection of unpowered (wind or motor) small boats or floating platforms otherwise. Engineering a floating breakwater effective in the open ocean is highly non-trivial.

    I would also recommend rescue divers or rescue swimmers in the water or on standby (they could practice rescues too) and full compliance with all Coast Guard and SOLAS regulations by all people at all times. Death by drowing (by a bunch of drunk, stoned and/or seasick people) may be slighly less likely if so.

    It would seem extrodinarily difficult to die at Burning Man or an SCA festival (though it does happen occasionally). Not so on the open ocean, or even a bay, epecially in drifting small boats or makeshift structures. A full seastead or very large ship, or small ship under sail or motor is probably much safer on the open ocean.

    Ephemerisle is an interesting idea for a lake or protected water, but it may not be very practical or safe on the open ocean.

    A problem with people living in the nanny state is that they increasingly expect other people to take care of them and become increasingly less aware of providing for their own safety and its real requirements. A truly free people need to learn to take full responsibility for themselves, including their own physical safety. Safety at sea is non-trivial under the best of conditions. It’s not incredibly different from safety in space: both are environments that can easily kill you.

    Profile photo of Patri

    Those interested in helping organize / run early Ephemerisles, I’ve created a mailing list:


    Profile photo of SailorTrash

    A lot of liveaboards/cruisers have a tender–a small dinghy of some sort–to carry them from their boat anchored way far out to shore, or another boat, or whatever.

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