I - 111 : Trireme - Antiquity's Guided Missile

The Greek Navy Ship Olympias somewhere in the Aegean

A few weeks ago I wrote about Persian Emperor (King of Kings) Xerxes' efforts in 480 BC to crush the Greek city states with a huge fleet of 700 ships. The backbones of his fleet were triremes, the standard warship at the time. They were provided by Phoenician towns, vassal states from Anatolia and the Greek cities and islands he had conquered the years before. Amongst scholars, there is a long-lasting debate where triremes were invented. In Phoenician or in Greece? There are good arguments for either. But there is insufficient evidence for a final conclusion. What can be said is that the trireme were based on simpler ship designs which we find in old carvings or texts.

Carving of an Assyrian Galley with two-rows of Oars from Niniveh at around 700 BC

Triremes were marvels of engineering – someone called them the guided missiles of antiquity. With their 400 kg bronze ram, they were lethal weapons. Triremes were racing boats which could reach speeds of 10 knots (18 km/h). At such velocity they could easily sink an enemy ship or break its oars as masterfully shown in the movie “Ben Hur” – my older readers must have seen it.

The Olympias during Construction in 1986 in Piraeus - The Oak Keel was laid down first, then the Hull was built with Pine then Oak Ribs were inserted. The Interior was made from light timbers such as Ash or Birch.

How triremes were built was forgotten though. In antiquity, master carpenters passed their knowledge orally on to the next generation. There were no blue prints. In Dubai, local carpenters still build dows this way. When the invention of Greek Fire (Napalm) in 500 AD made it possible to destroy enemy ships from a distance, ramming was not necessary any more. The know-how of building fast attack ships became obsolete. Galleys continued to be used but they became heavier and slower.

A Dow in Dubai under Construction in 2006 - there was a Master Carpenter but no Blue Print

A trireme optimised weight and propulsion to achieve maximum speed. Until the sea trials of the Olympias, a replica built in 1985 - 1987, most people believed that 10 knots of ramming speed was unachievable – a single person scull achieves the same speed. The claim was dismissed as ancient bragging.

The 170 Volunteers from England propelled the

Olympias to 9 Knots during the first Sea Trial

But today we know it is possible. A trireme is light. Without ballast its dry weight is just around 35 tons which translates into 200 kg per oar. Its draft is shallow, just about 1 meter. A trireme is so light that its crew can drag it out of the water onto the beach. Assuming 40 tons (with ballast), a friction coeficient of 20%, the horizontal force required is 8 tons. A man can pull at least 50 kg . 170 x 50 kg = 8.5 tons.

Volunteers boarding the Olympias for a Sea Trial

Keeping the triremes on land over night reduced exposure to sea worms and extended their life span. It also meant that these ships did not have to carry provisions except water for the crew – the oars men sweat so much that they do not have to pee! As we found out during our first sailing trip in 2017, galleys avoid staying at see over night and opt for ports or bays instead. They are too fragile to withstand heavy seas. Also, there is not enough place to sleep on board. Every rower just has his tiny bench.

Prof John Morrison on the Olympias during the Trials

We would know little about triremes today were it not for Prof John Morrison, a naval historian. He was intrigued by the many references found in classic literature which nobody could explain. It became his passion to find out how these ancient ships were built and operated. The BBC documentary “The Quest for a Greek Trireme” does an excellent job in telling the story. I could not do it any better.

Mock-up used in Boston 1988 to train Olympias Rowers

Over decades, with mock-ups and models Morrison figured out how 170 rowers fit into a space not longer than 35 meters (on 3 levels), what building materials the Greek used to keep the weight down (oak for the keel, fir, cedar or pine for the planks) and how structural integrity was provided by the Hyprozomata (rope). Together with retired British naval architect John Coates  and banker Frank Welsh the idea was born to build a trireme replica. When the Greek government learnt about the project, they supported it enthusiastically.

The new Olympias awaiting Sea Trials in Poros

The Olympias was built in Piraeus, Greece, from 1985 – 1987. It took considerably longer than the 6’000 man-days ancient sources mention. But many things had to be “reinvented” on the spot. Eventually, in 1987, the Olympias was ready for sea trials. 170 enthusiastic volunteers from England came to Poros and learned to row the Olympias over the next two weeks. The results were baffeling. The untrained crew achieved a speed of 9 knots (a modern single scull reaches 10 knots) and was able to turn 180 degrees within 2 ½ ship length. The Olympias was far more manoeuvrable than anybody had expected.

The Olympias under Sail for longer Distances

Over the years to come, the Olympias did many more sea trials with ordinary Greek who took “ownership” of their boat. It carried the Olympic Fire to Athens in 2004, visited the United Kingdom and the US and now stays at the Palaio Faliro in Athens. Definitely worth a visit this summer.

Olympias during Refurbishment in Elefsina Shipyard

in Greece in July 2003