• 12th June 2010 - By greg
    Hello!Clive and I are due to depart from Ucluelet on July 4th. The goal is to spend 10 days out to sea heading west – possibly in search of the Pacific high which in July, is typically found a few hundred miles west of Vancouver Island. I will pedal WiTHiN and Clive will sail the escort boat Theodora. Typical summer weather conditions in the north Pacific are good with the chance of a gale or storm low, so I am really hoping that I will be able spend the entire trip in WiTHiN. The advantage to going out with Clive, is that if conditions get dicey, or our recent modifications aren’t working out as planned, I will always have the option of getting a tow and climbing aboard Theodora. And we will be far away from any land which has been my highest area of risk with recent sea trials.

    As you may recall, a couple of my largest concerns resulting from my previous 2 sea trials – the first off shore in Ucluelet where I was knocked down my a strong wind gust and lost control, and getting caught in a wind storm on OK lake where I got a chance to really appreciate the danger of standing up through the open hatch to deploy a sea anchor or parachute.

    We hope that two new modifications will resolve these issues:

    1. Auto-drogue – This is a 10″ aluminum disc which will act as the drogue. It is attached to a 150 foot 1/4 inch thick cord which runs from the stern, through a small sleeve in the hull into the cockpit where it is reeled up with a trailer winch. I will be able to deploy the drogue with up to 150 feet of line all from the comfort and safety of my seat – and reel it all back in again. If this works, then it will be a really easy way to sit-out adverse wind conditions because the disk will provide enough drag to keep my bow pointed into the oncoming waves and wind.

    2. T-rudder – The T rudder is basically a horizontal wing that has been added to the bottom of the rudder. When wind blows abeam and rolls WiTHiN, the underwater surface area astern will increase as the horizontal ‘T’ wing rotates to vertical. This will increase resistance under water and allow the bow to be pushed down wind. That’s the theory, and I am anxious to see how this works in the real world.

    Photos are shown below.

  • 11 Comments to “Auto-drogue & T-rudder”

    • Jason Bordeleau on June 12, 2010

      only problem i can see is where you have the drone line going through that pipe it may cut into the line and you could lose the drone

    • Elrey on June 13, 2010

      You need a bombproof line. Kevlar? Spider silk. Greg, get the spiders on board as sponsors. Have ’em get to work.

    • Mitch Flanagan on June 13, 2010

      Hey, The T-rudder looks and sounds like a good idea! But…it looks kinda small? I sure hope it works for you. as for the drogue….I hope you’re using some really good quality rope for it! I’d be worried about it breaking off in rough water. But, I’m sure you’ve got that covered.
      I’m looking forward to hearing about the sea trials with the new mods. I sure hope you have favourable conditions for the trials, a little bit of the nasty stuff and whole bunch of calm sea’s.
      Have a safe trip!

    • Pete Hoffmann on June 13, 2010

      Jason is right the mouth of the pipe is a sever chafe point.

    • patrick egan on June 13, 2010

      Where the rope connects to the sea anchor, back splice the line around a grommet so that it does not wear on the anchor, trumpet the end of the pipe and vary the length of the rope every so often, also some kind of mechanical connection on the sea anchor so that when it draws into the hull that you could replace the sea anchor line with out it falling off… Just my 2 cents.. Not that anyone asked.

    • Russell Moore on June 13, 2010

      Perhaps a slightly cone shaped drogue would work better, and would be more stable in the water with the ‘point’ facing forward.
      I concur with patrick egan concerning the pipe and drogue rope.
      Also a swivel in the rope may prevent line twist, as no matter how symetrical you make the drogue, it will twist.

    • David Tangye on June 13, 2010

      Good comments.

      Also, a Kevlar line should go through the skin fitting OK, as long as the outer braid is not a soft weave. Whip it onto a small ss rigging thimble so it wont get abrasion and break at the end fitting. It will draw a bit of water inside on retrieval, and perhaps at other times too, so have an absorbent cloth nearby to mop it up. Perhaps mount the retractor winch in a shallow plastic pan? Ignore my earlier comment about a cone shaped drogue: I thought it was retracted onto the bow :-).

    • Xabier on June 14, 2010

      Greg, have you seen this website?:
      http://www.expedition360.com/reference/design.htm
      STEVE SMITH and JASON LEWIS set off from the Greenwich Meridian on the 12th July 1994 to attempt one of the last great firsts for circumnavigation of the World. Steve decided to leave the expedition upon reaching Hawaii in 1999. Jason carried on solo and is still on course to complete the circumnavigation in October 2007.

    • Bruce Bolster on June 17, 2010

      Patrick Egan’s suggestions are good ones. I agree with Russel Moore’s comments about the shape of the drone – a flat one will likely flutter and precess like a fishing lure – it will want to gyrate in circles.

    • Jarl on June 17, 2010

      Apart from that drogue likely being wobbly in water, it will also be a unwelcome wind resistance if pedaling against the wind. (And of course a welcome micro-sail if going down-wind, but this is not a sail boat so..).

      Hopefully the rudder mechanism is strong enough to cope with the increased area and grip of the rudder. Possible to bend/break the rudder axle if under harsh conditions? (And btw, what is your plan if the rudder break? Abandon ship or is there some backup solution? I’ve seen that you have a backup drivetrain, but rudder failure would likely also be a major problem?)

      I still think you will need a keel with more area to reduce side-to-side movements and a bow with more volume to improve the boats ability to handle big waves, but hopefully I’m wrong.

    • Jason on June 28, 2010

      I’ll echo what’s been said before… in any kind of storm conditions that drogue line is going to chafe through in no time on the edge of the pipe it’s exiting from. You can “trumpet” the end of the pipe, or have a toroidal piece of HDPE machined, and attach that to the end of the pipe. If you have the rope contacting a large-ish radius piece of low-friction high-density plastic, it’s much less likely to chafe.

      As for the drogue itself, I’d be concerned that it might be so light that it would just skip across the surface. When sailboats put out sea anchors, they often weigh them down to make sure they stay in the water, and below the level of surface waves. Were it me, I would go with a heavily-constructed cone-shaped cloth drogue, with some sort of weight added to it to make it both self-deploying and to keep it uner the waves… something along the lines of this http://www.smartmarine.co.nz/easy-stow-25-drogue-sea-anchor-boats-to-7mtr-p-5586.html

      Have you had anyone calculate what the forces on the “T” of the rudder would be if you broach and are pushed sideways through the water? Is your rudder assembly strong enough to take those forces without warping or breaking?

      I don’t know if you’re dead set on running downwind in storm conditions, but have you considered pointing upwind instead? With as light as WiTHiN must be, it probably wouldn’t take much of a “fin” sticking up into the wind to weathercock her around to pointing upwind… I’m picturing something like the dorsal fin of a fish, set well aft, that you could raise in storm conditions.

      Cheers!
      Jason
      Calgary, Alberta


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