The seamanship of the Barbary pirates of North Africa was for two centuries as renowned as their cruelty as they plundered Mediterranean shipping lanes for slaves and treasure.

The key to their hit-and-run tactics was the fast getaway. They were able to sail far closer into the wind than the Europeans left trailing in their wake. The pirates ceased to be a problem after the French conquered their raiding base, Algiers, in 1830 — and the secret of their crucial advantage was lost.

Now a tall ship with a full set of sails based on the pirates’ ships has successfully completed sea trials. TS Pelican, a 150ft converted trawler, has been fitted with the masts and sails of a polacre xebec — a design last seen plundering shipping nearly two centuries ago. The Pelican, whose trials took place in Wey-mouth Bay, did what no European square-rigged vessel could do before or since.

Research by the sail designer Philip Goode had revealed significant details of the xebec-style vessels with their mix of square and lateen (triangular) sails. Geometric experiments enabled him to work out how the pirates had been so well able to sail into the wind.

After trials with a model, Mr Goode and the project director, Graham Neilson, fitted the Pelican with five sails at the front that mimic the geometry of a single huge lateen sail, and square sails on yardarms behind them. The front sails give the boat lift; the square sails give her thrust. The sails are cut exceptionally flat to give the ship the ability to go to windward. The square sails can turn in unison because the mast is one long pole. Conventional square riggers had stepped masts and rigging that prevented such movement.

During trials the Pelican was able to sail at nearly 10 knots at 38 degrees off the relative wind. Mr Neilson, a former Royal Navy commander, said: “The Pelicancan sail over 20 degrees nearer the wind than any square rigger at sea. The yards come to within 18 degrees of the centreline. It is a combination of the fore and aft and the square sails, along with the aerodynamics, that is the secret of how to move so close to the wind. I think we can get more out of her. It could really tear up the field in a tall ships race.”

The Pelican has a crew of 30 trainees with eight instructors and specialises in long-haul voyages.

George Hogg, a trustee of the National Maritime Museum Cornwall, said that the ability to sail into the wind gave those who fought at sea an advantage “like the acceleration of a racing car or the climbing rate of a jet fighter”.

Peter Goodwin, an expert on the pirates, said that their ships had guns at the bow and stern. “They would approach, pounding away, and it took too long for our square riggers to bring the broadside guns around. The Arabs had oars and a sail arrangement that meant they were able to turn more quickly and could flee closer to the wind than we could chase them. In the late 17th century we even began to introduce oars to our ships to try to compete.”

Shock tactics

— Barbary pirates raided villages along the Devon and Cornwall coast, setting up a base on Lundy Island

— Watches were kept from church towers and some villages moved inland

— Those taken were sold in Algiers slave markets or worked to death as galley slaves

— Thomas Jefferson and John Adams, then US ambassadors to Paris and London, demanded to know why American ships were being raided

— They were told: “That it was founded on the Laws of their Prophet, that it was written in their Koran, that all nations who should not have acknowledged their authority were sinners, that it was their right and duty to make war upon them and to make slaves of all they could take, and that every Muslim who should be slain in battle was sure to go to Paradise”

Source: Times archive

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