Student_Driver

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Everything posted by Student_Driver

  1. Student_Driver

    Secret Hallberg-Rassy project

    Judging from the deck hatch, this is the HR 64/62 update...
  2. In the thread about lusting yachtworld boats, there's a mention of a 74 foot sailing yacht (SY Gefion) listed in northeast Europe which has a very interesting and esoteric system for controlling the boom swing in a gybe. There is what looks like a second, massive Vang structure that connects to a very beefy large steel shaft extending down to the bilge where there's a very large cog mechanism with a rack and pinion on either side attached to hydraulic pistons. It appears that the system is intended to slow down the motion of the boom and by all appearances the engineering is robust and it looks like a very interesting solution for larger boats were boom brakes don't work due to size. I've been reading a very long thread on another website about the Platino disaster over a decade ago which focuses predominately on the pros and cons and mathematics of different preventer arrangements for boats above 50 feet. My current boat and next boat are in this category and I'm very interested in safety. I'm wondering if anyone has ever seen this mechanism or one like it? In one of the listings they describe it as "Gybe Draulic" or sounds like a brand name but there's nothing online suggesting that this was made only one time? If I were to have my druthers, there would be some way of slowing down the motion of the boom but not completely arresting it causing a back winded situation. For those not familiar, SY Platino was a 66 foot sloop which had undergone a massive refit which included installation of a furling boom which weighed around 1.600 lbs. There was an issue with leaking hydraulic pressure in the auto pilot ram causing the boat to wander heading during a deep down-wind run in a confused sea state. Waves from coming three directions and wind gusts up to 48 knots. The boat gybed and the inadequate preventer mechanism broke causing the traveler to explode killing the helmsman and caused a second fatality when another sailor got knocked off the boat by the swinging mainsheet/traveller. https://www.yachtingworld.com/news/new-zealand-death-mob-tragedy-76516 https://www.yachtbroker.se/baat/sailing-yacht-gefion/4759
  3. Student_Driver

    Lusting on Yachtworld

    in the Gunboat 55 listing it says: ”Her winches are manual, and can be powered by their handheld electric powered handles.” . For two commas, I want to push buttons.
  4. Student_Driver

    "Gybe Draulic" Preventer on SY Gefion

    Seems crazy that they haven’t removed it. Sounds like a 22 year old ticking time bomb. When R’zer explains it the forces are magnified by the ratio of 25’/2.5” or about 120:1. Wow.
  5. Student_Driver

    "Gybe Draulic" Preventer on SY Gefion

    @Tylo sent me this photo. That geared cog is at the base of the shaft which in turn is attached via the strut to the boom. From what I've read, the gears on the cog drive the hydraulic piston shafts which dampen the motion of the boom.
  6. Student_Driver

    "Gybe Draulic" Preventer on SY Gefion

    @Diarmuld, I think I misled you. The base of the GD is not linked to a dynamic/controllable hydraulic system but rather to hydraulic shocks like on the suspension on a big truck... Think of a massive truck. In my experience, sealed hydraulic pistons don't fail frequently but do have a finite life. Having said that, I agree generally with your assessment that there would be multiple failure points and it's probably not practical or reliable.. OTOH, Gefion is 22 years old and the system has not been removed. Am guessing that it 'does no harm' at least.
  7. Student_Driver

    "Gybe Draulic" Preventer on SY Gefion

    Max, Pls send me a link for the Dock Clamps and Auto Watchkeepers. Just what I need for my 48,000 pound boat. But seriously. Thanks for making me laugh.
  8. Student_Driver

    "Gybe Draulic" Preventer on SY Gefion

    I don't mind complexity, I just want to understand it. It seems to me that whenever you add complexity and automation to the boat you expect higher expenditure, more rigorous and extensive maintenance with the risk that the system fails precisely when you need it most. For me the best example of this is the auxiliary which fail with unfortunate frequency during storms and while docking. Nonetheless we accept that trade off and we do our best to maintain our auxiliary so that we have the highest chance that it will work when needed. On the other hand, prudent sailors have back up plans and know how to operate manual back up systems. Sailors tend to be very slow at adopting technology and often eschew technology being used successfully offshore by racers and record setters. Sometimes technologies are rejected simply based on cost. Clearly, this device has not been adopted broadly which suggests that it was not a resounding success or complexity and cost make it impractical. Without hijacking my own thread, there are debates over best practice with regard to preventers. Unless I am mistaken, the divide seems to be between having a preventer with a given and predictable stretch or breaking point (a.k.a. "fuse") versus massive and unbreakable and no stretch. Whilst I've seen some arguments about placement of the preventer on the boom (many seem to suggest a third of the way back from the end or all the way to the end depending on how much pressure your gooseneck to take) and the placement of the turning point or attachment point of the preventer at or near the bow. These arguments seem less controversial and opinions are more aligned. I personally don't like the idea of a massive and unbreakable preventer. I'm not really a big fan of the fuse strategy either. Next season I plan to re-rig the boat and will need to do some work on the exact amount of stretch and rigging for a new preventer system. The hydraulic system in question is not on the shortlist but it does seem intriguing and could the ability to scale in size to absorb larger loads (vs a boom brake) at a cost measured in: weight, effort, risk and burnt money. Horses for courses.
  9. Student_Driver

    "Gybe Draulic" Preventer on SY Gefion

    Reading it now. Thanks.
  10. Student_Driver

    Lusting on Yachtworld

    @Tylo Thanks for sharing that. I’ve never heard of such a device but it seems to be sensible, simple and safer than many preventer setups. Accidental gybes account for a great many MOBs and serious injuries. Has anyone seen a device like this?
  11. Student_Driver

    Center cockpit vs aft cockpit

    Falcon 8X Think Jimmy Buffet has the 7X. He sails that deck salon surfsri 50
  12. Student_Driver

    Center cockpit vs aft cockpit

    Either of these birds would do nicely... Suppose these should be considered Forward Cockpit.
  13. Student_Driver

    so who's heading to the caribbean this winter?

    Looking good Billie Ray
  14. Student_Driver

    Center cockpit vs aft cockpit

    Look like a Falcon 900. Recent vintage. That and the 7X are great rides.
  15. Student_Driver

    Yankees are cunts

    anyone who uses the c-word is a douche.
  16. Student_Driver

    Daysail this weekend,-Noroton CT

    I could use two to join me and one or two landlubbers on Indigo (a 52’ aluminum sloop.). Just a daysail. Broad reach for a bit unless it’s too wet or cold.
  17. Student_Driver

    Expedition To The Ege...

    Never been there, but your observation would appear to pass the sniff test.
  18. Student_Driver

    Expedition To The Ege...

    Like when they talk about the cold and layers of clothing keeping their body odors under control. Nice.
  19. How did the Alerion sink due to a broach?
  20. Student_Driver

    Aluminium Centerboard 46-52ft blue water go anywhere

    It’s funny. I spent a decade dreaming of an exploration style sailboat with a pilot house or hard dodger (like amel) but ended up with a traditional styles 52’ aluminum cutter with a centerboard and an open aft cockpit. While I feel envious of the deck salon Nav stations (few have steering), I must admit that I like having a pretty boat. When I look at my boat, my eyes get happy. That does not happen when I look at a more practical design like the Garcia or others in the thread. The thing is that her center of gravity is very low. She has a 40% ballast ratio; she has adequate overhangs and she rides like a dream. We had 12’+ quartering seas on a short interval on a recent trip to Maine (east /outside of Cape Cod) and she was super solid and comfortable. I now believe that ride quality and center of gravity are super important and I’m not sure these explorers necessarily have a more comfortable motion at sea than my ship. Perhaps I may be wrong. YMMV.
  21. Student_Driver

    Used boat with rod rigging

    Navtec. Too funny.
  22. Student_Driver

    Used boat with rod rigging

    I need to have my nobeltec rod rigging inspected or replaced. Who would you in the CT/NY/RI/MA area?
  23. Student_Driver

    Everyone is buying boats...

    Looks American, probably Burger.
  24. Student_Driver

    Super yacht super times

    NZK posted on the My Song Fell off a Containership thread on Aug 8th. Thanks
  25. Student_Driver

    Super yacht super times

    I used to think that I’d want one of those if I hit the jackpot. Today, not. So many reasons but the recent account in the Sailing forum about one anarchist’s personal experience with a broken boom on a 120’ sailing yacht is sobering.