Will Moore and friends were on hand in 2006 when a completed boom was launched. Thank you Will for sharing your photographs and solving the mystery of how such a huge craft is moved from the construction site to the water.
Will prepared a Powerpoint presentation of the launching of the boom in 2006. To download a copy of his presentation, click here. His presentation includes photographs of the racing dhow construction yard next door.
The first visit was in February, 2005.
The second visit to check on the construction was in July, 2006.
Estimated capacity 900 tonnes and approximately 40 meters or more than 120 feet long.
By the time Will and friends arrived for the launch, the hull had been finished with a coat of pain up to about three meters from the keel and a sealant used on the upper planks. Previously all bolt and nail head had been filled with putty and the gaps between the planks sealed with cotton.
The launch process begins by lowering the boom onto a crib. While under construction, the keel beam sits on large wooden blocks. When ready to launch, the crib is constructed under the boom and the wooden blocks under the keel beam removed by digging them out of the sand.
The crib consists of two long beams with cross members to keep the smaller pieces of wood in place. The beams are placed on rollers which, in turn, roll on a path of three planks. The rollers are lengths of pipe filled with wood. On the beams, wedge-shaped pieces are placed between timbers until the hull is resting on the crib. Finally, the wooden blocks on which the keel beam has been sitting are dug out from the beach sand and the boom rests on the launching crib which will roll to the inlet.
The crib, in turn, is pulled via a Spanish windlass to the water's edge. This takes place at low tide, when the boom can be moved to a location where, when high tide arrives, it will float.
Wire rope is used on the windlass, along with a block purchase -- pulleys -- so that a team of a dozen men can rotate the windlass and drag the boom across the placed planks. One man guides the wire rope through the windlass to ensure it does not get tangled.
The windlass is secured by two large anchors placed in the sand.
There are two windlasses on site; for the launch Will and friends witnessed, only one windlass was used.
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