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March 09, 2005
Ferry to the island
A large dhow serving as a ferry to Palm Island from West Beach
The quality of the water and the attraction of water for small boys everywhere is evident in this picture of the West Beach to Palm Island ferry. The large dhow is quite stable even with both decks fully laden, and she is also quite quick with her large marine engines and the shallow hull designed for fast sail driven passage. Palm Island can be seen under the bows of the ferry and is a sand bar that has been built up and developed as a feature in the now semi-circular bay that is such a feature of Doha.
The quaint hull design with its almost outdated appearance is deceptive. These are extremely sea-friendly and sea-weatherly small ships. Sixty years ago these vessels would not have had engines but would have had a single mast mounted just forward of the centre on which they carried a long spar, secured near the prow by a block and tackle and from which hung the huge lateen sail. This is not a rig designed for "tacking", that is, working a ship to windward against the wind; instead it is extremely efficient on long voyages employing the monsoons which blow East or West across the Northern Indian Ocean or the Arabian Sea. Since the rig is designed for the fastest point of sailing for any sailing ship - the broad reach, that is; across the wind - the dhows hull is designed to take advantage of that and, even under load, it tends to lift at speed and "plane" across the water, achieving very good speeds. The very different sailing conditions encountered in the Atlantic, the North Sea, and the Baltic have meant that this rig never really worked effectively in European waters, but found some favour in the Mediterranean. Of such "mishaps" of meteorology and geography sometimes comes the impetus for divergence of development.
Lateral and directional stability is achieved by having a long keel which increases in depth as it travels aft. Take a good look at her lines - many modern yachts have the same broad "cheeks" aft and the fine "entry" forward, for very much the same reasons as those for which the dhow was designed - speed and stability.
The modern dhows seem to have managed to blend the best of their hull form with the modern propulsion systems to very good effect. Obviously the hallmark of a sound hull design to begin with.
Posted by The Gray Monk at March 9, 2005 09:07 AM
Comments
Are there any of the old fashioned ones with lateen sails left in those waters?
Posted by: The Scarlet Manuka at March 9, 2005 08:34 PM
I understand that there are some, but have not seen them. From what I am told they are mainly confined to the Red Sea area between Saudi Arabia and Eritrea or Somalia.
Posted by: The Gray Monk at March 12, 2005 04:16 AM