Lock Crowther Biography

Discussion in 'Multihulls' started by oldsailor7, Nov 20, 2009.

  1. oldsailor7
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    oldsailor7 Senior Member

    I was browsing the web and came across this Bio for Lock Crowther.
    It may be of interest to Locks fans.

    Lock Crowther

    Famed muli-hull designer of Australia. Among his most notable designs were the Buccaneer & Kraken series trimarans, Spindrift 45 & Catana 40 cats, as well as a great number of other cruising, racing, charter/commercial and power cats and tris.
    Lock Crowther built his first boat, a trimaran called BUNYIP, in 1959 while still a teenager. The following year he raced in the Easter regatta at Paynesville, Victoria, Australia, beating 300 boats to the finish. The success of his boat inspired several of his friends to build similar boats and thus Lock Crowther’s design career started, though he did not expect to make a living out of it, and studied electrical engineering. In the early 1960s, when there were only a handful of people designing multihulls, Lock Crowther was involved in this international scene and also a member of the Amateur Yacht Research Society.

    BUNYIP was followed by the Kraken 25 design, which somewhat widened Crowther’s recognition. His reputation was established internationally in 1996, when his first offshore racing trimaran BRANDERSNATCH won the Sydney to Hobart multihull race. Even more notice was taken in 1966, when a Kraken 40 won the New York to Bermuda race with him aboard.

    During Lock Crowther’s career, more than 2500 of his designs were built. He started out with racing boats, where most of his new ideas were developed, though he was successful drawing cruising and commercial craft as well. Among his outstanding designs was the trimaran SPIRIT OF AMERICA, which was an early user of GRP-foam sandwich construction and had innovative composite beams with uni-directional fibres and turned-down ends. Lock Crowther also developed the use of ‘bulbous bows’ as a measure to reduce pitching, and hence increase speed when sailing upwind in a swell.
    Since his death in 1993, Crowther Designs was run by Lock Crowther’s son, Brett.
    On the 27th of July 2004 Crowther Pty Ltd was shut down and the company name de-registered.
    Brett moved on to join INCAT P/L to form INCAT- CROWTHER, and concentrate on development of commercial vessels. Lock Crowthers DIY multihull sailboat plans are now permanently archived and no longer available.
    Last edited: Nov 22, 2009
  2. bad dog
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    bad dog bad dog

    I had the great pleasure of racing on Lock's own last boat, a 48' cat named Deguello (built 1989 in Gladstone QLD), which moored then in Pittwater (just north of Sydney), now sold and gone to Hobart. Lock actually died on board of a heart attack I think, and I'm sure his ghost assisted in getting us fired up when needed. He was a very clever man, and all multihull designers now stand on his shoulders (amongst several others!).
  3. oldsailor7
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    oldsailor7 Senior Member

    Yes it was a bit sad.
    Deguello was about 1 1/2 NM offshore when Lock suffered a heart attack and was given resusitation to keep his heart beating. The ASR helicopter was on the scene in record time but the mainsail hung up on a jammed track slide and could not be lowered. As a result the heli was not able to land a small team with life saving equipment. By the time they came out in a fast boat it was too late. RIP Lock. :(
  4. sabahcat
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    sabahcat Senior Member

  5. oldsailor7
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    oldsailor7 Senior Member

    Lock had many, many friends and aquaintances. If any of you have anecdotes, or tales to tell, of Lock and his lifetime, it would be nice if you could see fit to tell them here in this thread.
    A lot of us would be really interested.
    For instance here's one.

    Lock had a very dry sense of humour.
    When He and Logan Apperley came over to Canada for the World Multihull Symposium in June 1976, They sailed with my wife and I on our Buccaneer 28 No:1 in an overnight race on Lake Ontario. The next morning we were sailing along in light winds when Logan went out onto the bow of the Stbd float to hank on the spinnaker pole downhaul----and promptly fell overboard.
    There was a moment or two of ghastly silence and then two sets of white knuckles showed up on the rail at the aft end of the float.
    Without missing a beat Lock shouted, " Logan--stop mucking about and get back on board" I'm sure Logan will never forget that.
    1 person likes this.
  6. Ad Hoc
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    Ad Hoc Naval Architect

    He worked as a customer rep, for a client, in the company i worked at in the early 90s. Was bloody tall, as i recall, nice bloke easy to chat with. He sadly died shortly after the project was finished.
  7. Corley
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    Corley epoxy coated

    I found the following on the web sadly it seems Howard Stephenson has passed away as I've tried to contact him without success to let him know I was doing up Lock's Kraken 25 Trimaran. Out of interest does anyone know what became of Trio or Bunyip? I'm also interested as to the fate of one of Lockie's later daysailing tri's Jabberwock.


    I have learnt a lot from my friends. Stuart Harris and others taught me about amateur radio. David Theobald and I together learnt saltwater light game-fishing. David Williamson showed me how popular songs were constructed. Lock Crowther taught me a lot about how boats were designed and stimulated my interest in learning more.

    His real name was Lachlan, but he couldn't stand it, and insisted on being called Lock, or Lockie. I knew him slightly from our home town, Bairnsdale. In 1960 or 1961 we ended up by coincidence in the same Melbourne boarding-house. We were both part-time students. As Lockie had a car, he would sometimes give me a ride home to Bairnsdale for the weekend. On one of these weekends home I went to Paynesville, about 15 Km from Bairnsdale, on the Gippsland Lakes. This was one of my favourite places, because of the boats there. There was the Government Slipyard, with its two RAAF crashboats. I loved to peer through the portholes at their triple straight-eight Packard engines. Tied up near the slipyard were rows of fishing boats and cabin cruisers. Between Christmas and New Year there would be speedboat races on the lake. Home-built Bondwood three-pointers powered by modified V-8 car engines would tear around the course at speeds reaching thirty knots and more.

    There were sailing boats at Paynesville too, but they were too slow to attract my interest, until one Saturday afternoon I saw something that moved like a speedboat with sails. From a distance of half a kilometre or so I could see a huge plume of spray arcing out from either side of the boat as it rocketed towards Montague Point in a gust of wind. I wanted to be on that boat.

    I knew that Lockie and his family were keen on sailing and that they had built a trimaran. As the sailing speedboat I saw that afternoon was a trimaran, I guessed, correctly, that it belonged to Lockie's family. It was not long before I'd wangled an invitation to go sailing.

    Their trimaran, 6 metres long, had been designed by Lockie and built out of plywood on wooden frames and stringers by him, his two brothers and their father. Maybe his sister and mother had a hand in it too; they were a close family. The tri was sloop-rigged with a wooden mast. The balanced jib was attached to a boom. The decks between the main hull and the floats were plywood. In an effort to provide lift, the floats were flat-bottomed. Although this feature was not an absolute failure, more often than not it just created extra drag. The trimaran was named Bunyip, after an Australian mythical creature.

    Another feature, intended to prevent broaching, was the very full bow on the main hull. This was the reason for the twin jets of water that came off the forefoot, ensuring that at any speed at all the crew became absolutely saturated.

    On my first outing, we were three-up; I was just a passsenger. As the wind was fairly light, the Crowthers had rigged a single-luffed spinnaker as a genoa. One of the brothers was out on a trapeze and Lockie was steering. I just sat there, thrilled by the water hosing off the bow into my face, by the rush of wind and by the streaming wake. I was hooked, but I was still a student, with no spare money at all. Building a trimaran myself was out of the question, at least for the time being.

    Lockie, feeling that he could do better with a new design, started work, in a Melbourne suburban backyard, on a cat-rigged single-hander about 600 mm. shorter than his first effort. The sail was fully battened, with a huge roach. The side-decks were plywood. Instead of a trapeze, there was a sliding seat which could also be pivoted fore and aft. A new idea was the use of a daggerboard in each vee-bottomed float, canted inwards at forty-five degrees so as to provide both lift and lateral resistance. There was also a conventional daggerboard in the main hull.

    This design was not a success. It was too heavy, because of the sliding seat and because it was built out of heavy hardwood plywood instead of the fir plywood which had been to build the earlier design. Being deep in the water, having no jib and with two off-centre daggerboards, the tri would not tack properly. It was almost always necessary to back the main and reverse the rudder to get onto the new tack.

    Lockie's next attempt was an even bolder step into the unknown. Fortunately, it was much more successful. At that time racing in C-class catamarans for the "Little America's Cup" was all the rage. Lockie decided to design and build a C-class trimaran. The C-class rules required a maximum length of 25 feet (7.6 metres) with a sail area of 300 square feet (28 square metres). At that time his ideas were somewhat influenced by Scandinavian square-metre keelboats, whose main design restriction was also a fixed sail area. They seemed to go well with their large overlapping jib, a genoa, just as Lockie's first design went well in light airs with a genoa. So the new design featured 28 square metres of sail area, about 11 square metres of it in the genoa. This allowed a relatively short aluminium mast, just over nine metres tall, as I recall.

    The main hull was quite different from any of the C-class catamarans. The curved forefoot carried forward into a very fine overhanging curved bow. The mid-section was a conventional (for a multi-hull) semi-circle, but the bottom was flat by the time it reached the transom. The floats had a similar bow, but with a vee-shaped midsection; the afterbody tapered towards a triangular reverse transom. I am not sure where these ideas came from, but they certainly produced an elegant shape. I guess he was trying to minimize wetted surface area and reduce hobbyhorsing. Lockie drew up a nice set of plans for this boat, including an isometric projection which I greatly admired

    The three hulls were cold-moulded, with a lot of effort put in by his family, and some by me too, stapling the veneers, then pulling the staples out after the glue dried. (This reminds me of the way ships were built in the days before the steel plates were welded together: half the building crew would be making holes in the plates and the other half filling them up with rivets. Some aircraft are still built this way, although not with steel plate, of course.)

    By now I was earning a proper wage and I wanted to build my own trimaran. For someone who had never made anything more difficult than a doorstop, this was a major decision. I reckoned that I could rely on Lockie and other yachtie friends to advise me on boatbuilding, and save a lot of time by purchasing a ready-made main hull. But who made stock trimaran hulls? No-one, of course; but Charles Cunningham was turning out fibreglass shells for his 6-metre Austral 20 catamaran. I bought one of these, decked it with plywood, built timber-and-ply crossbeams and floats to Lockie's design and fabricated much of the hardware from stainless-steel plate. E.F. Prior of St Kilda made up a genoa and fully battened, heavily roached main out of sky-blue Terylene. The spaces between the hulls were filled with two canvas trampolines, also made by Prior at what my mother considered an exorbitant price. The result was a cut-down version of Lockie's latest creation, with seven percent less sail area, less beam and length and a lot less weight.

    Instead of a daggerboard, I followed Cunningham's idea of using a leeboard. Once we solved the engineering problems -- I broke several boards -- this set-up worked quite well, but obviously was less efficient than a daggerboard. Eventually I discarded the leeboard, glass-and-epoxied a daggerboard case into the hull and made a nice hardwood daggerboard which never looked like breaking. This arrangement proved to be much more efficient. This was the first time I had used epoxy resin. In those days it was very expensive and hard to come by. One of the Bulmer brothers was an industrial chemist and he was able to purchase some for me at a reasonable price. It was as thick as treacle on a winter's day, so I would scoop out each small batch into a pot, heat it on the kitchen stove to bring it to a manageable viscosity, mix it with the right amount of hardener, then apply it very quickly before it started to set.

    Meanwhile, Lockie's larger tri, which he named Kraken, was performing well on the Gippsland Lakes. Admittedly the only competition came from Lightweight Sharpies and Flying Dutchmen, so it was hard to gain a comparison with other similar boats -- C-Class catamarans, for instance. In due course I finished my boat. It should have been up with his, at least in light airs but, partly because of my inexperience, my "Trio" was hardly ever a match for the bigger tri. There was one occasion when Trio beat them all, Kraken included: one of the Gippsland Lakes Yacht Club's annual long-distance races. The course was set from the yacht club at Paynesville, south-west along Lake Victoria to Waddy Point and return, a round-trip of about 15 nautical miles. As there was a gentle south-easterly sea-breeze that day, the course was virtually two long reaches, with no tacking and just a gybe at Waddy Point. We won easily, in record time.

    We also used to cruise the lakes although, without auxilliary power, we ran the risk of being becalmed. Once Hugh Crowther and I took Trio for a day-sail to Lakes Entrance, about 15 nautical miles from Paynesville. We arrived there in good time, had our picnic lunch and headed for home. By the time we got to Metung, only half-way back, it was dark and we had run out of wind. I had to call my father to come and drive us home. We sailed the boat back to Paynesville the following weekend.

    Lockie once took Kraken to compete on Port Phillip Bay. It turned out not to be competitive against large catamarans. They were designed for the bigger seas and stronger winds of the Bay. Our tris excelled in the light breezes and small chop which we mainly encountered on the Gippsland Lakes.

    This was fun, but even more fun was when there was a beam reach in a stronger breeze. The sheets would be just started, the apparent wind being well forward of abeam. My crew would be out on a trapeze and I would be out there on a trapeze too, barely maintaining control via the tiller extension, nearly three metres long.

    I also enjoyed light-weather sailing. Neither tri had a spinnaker, but we hardly needed them: our technique was to tack downwind, heading up in the lulls and bearing off in the puffs. Even to windward both tris were faster than all the monohulls, although we would lose out if there was any short tacking to be done.

    These good times eventually came to an end. I left for Queensland, returned briefly, sold my boat and went overseas. Lockie decided to give up his day job and move to Sydney where he became a famous and successful designer of trimarans and catamarans.

    Nearly forty years on and living over a thousand kilometres from the sea, I still daydream about boats. These days my interest has returned to powerboats, because I enjoy fishing and need plenty of shade; my skin no longer lets me sit out under the sun for hours. Maybe I can find a design somewhere for an easy-to-build trimaran which could be fitted out with minimal camping-style accommodation and powered by a smallish outboard engine.

    Howard Stephenson

    November 1999
  8. rebel1
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    rebel1 New Member

    I too had been "touched" by Lock in late 1969 and 1970 but not by involvement with his early racing designs. In January 1970 I was transferred by my employer to Townsville NQ., where I found two of Locks early cruiser/racing designs had recently been launched. Both boats were 33ft long and of a design by Lock called I think "tempest" versions.

    One boat called Jindivik was owned by a Don McGrath, the other by a local engineer, Ian Hamilton, was called Nomad.

    These boats were full bridge deck versions of what was known as the Kracken 33. Slightly wider in the main hull than a Kracken, a habitable cabin, and in the case of Jindivik a small cabin aft of the rear beam, cold molded round bilge plywood construction with what today could almost be called a center cockpit. Nomad's cockpit was in the stern and one would sit on the rear beam and tiller steer.

    Both of these boats "owned" the Townsville Cruising Yacht Clubs easter race to Dunk and the Townsville to Whitsunday series in the early to mid 70's.

    Jindivik in fact held the Townsville Dunk Island race record for many years prior to it being beaten by a later Lock Crowther design. The race was 96Nm as the crow flies and Jindivik finished the course in 8 hours 16 minutes. Very quick in those days.

    I had the pleasure to be crew on Jindivik during that race ( and many other races) and can remember the boat surfing down huge waves, completely controllable, and us, the crew, celebrating whenever the log showed over 20knots.

    Mid 70's saw Don Hinch sell Manta 11 to a local doctor and I had the pleasure to sail on this boat during a Townsville to Brampton Island race.

    In short, I have a huge respect for Lock I must, now my memories have been revived, contact Lock Crowther’s son, Brett to see if he has copies of the "Tempest" design.
  9. brian eiland
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    brian eiland Senior Member

    Lock Crowther's Work

    Did you post, or was there posted another such subject thread on that other forum about Lock's designs??

    I had gathered together a couple of his yearly 'portfolios' and scanned some of his better designs with the aim to post them over on that forum. I got distracted by other work and forgot about the project. I'm sure those scans are somewhere around my office.

    To my knowledge there is no one really actively selling Lock's old plans, so I thought it might be OK to post some here on these forums to keep his memory alive??

    ...what a great guy. I met him on several occasions when he visited the USA.
  10. Barba 22
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    Barba 22 New Member

    Crowther Tempest 37 question

    Hello everyone,

    I have a question regarding a Crowther Tempest 37 trimaran. Can anyone give me some information on that boat? I found virtually nothing on the internet, so every bit of information will be very appreciated. The intended use would be cruising in the Indian Ocean.

    The actual boat can be seen here:


  11. rebel1
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    rebel1 New Member

    Barba, My recollection is that the Tempest was designed by Lock at 33 feet. Having said that, I do know that one of the boats I referred to in my earlier post, "Nomad", was lengthened by extending the stern in an effort by the owner to beat his rival "Jindivik".

    Looking at your pics I would suspect that boat has had the same treatment as the skeg hung rudder was under the stern in the standard design and the transom was more upright and immersed at rest. This modification would make the boat about 37 feet LOA.

    Although I have had no contact with the builder of Nomad for many years I believe him to still be in Townsville. Should you wish to know more then send me an email to rebel3 at tpg dot com dot au and I'll pass on what details I have to enable you to contact him. Change the email address to a normal format.
  12. Gary Baigent
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    Gary Baigent Senior Member

    Barba22, here is a crappy reproduction from an old AYRS.

    Attached Files:

  13. rebel1
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    rebel1 New Member

    Gary, Thanks for that copy. Sure brings back some memories of not only very pretty boats but very quick ones at that.

    I consider myself very fortunate to have sailed on designs by two pioneers of Tri's in Aussie land. Lock and Hedley Nicoll were the driving force of the industry at that time.
  14. catsketcher
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    catsketcher Senior Member

    I never sailed the Tempest but had a Twiggy. The Tempest was in Lock's first attempt at a cruising tri range - Zephyr, Tempest, 38 foot Impala and a larger one as well.

    I thought the Tempest looked a little fine. It was drawn before Lock and John Hitch drew the Kraken 33 (Lock told me the design was a collaboration) After Bandersnatch he beefed up the designs.

    The tri will be an old design with little load carrying or volume inside for its length.



  15. Barba 22
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    Barba 22 New Member

    Hello and thanks for the input. It's very much appreciated.

    I understand that the boat doesn't have very much space inside but it's not so much of an issue in the tropics. It's the space outside that you want there. A small cabin to hide from the rain when sailing, is more or less sufficient. At anchor, you rig a peace of cloth over the boom and you're fine.

    However, I was not able to figure from those pictures how much space really there is on the deck. Also, with no daggerboards, I wonder about the capacty of that boat to sail to weather, especially in short, steep seas?

    The carrying/loading capacity is more of an issue than the size of the cabin. Even though I intend to sail "light" (no 40KW genset to run the 15' plasma TV...) , I have to carry some rice and beens, and some chain and anchors...

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