An inventor born in Co Mayo secured Ireland's place in military history,writes Mary Mulvihill
We don't normally think of Ireland as a major player in the weapons industry, yet the guided missile was invented in 1877 by a talented engineer from Castlebar, in Co Mayo. Louis Brennan also designed an unusual monorail train, a two-wheeled car and even an early helicopter.
His greatest success was his missile system, essentially a torpedo that was fired from the shore and then steered using guide wires. Widely deployed by the British navy, it made Brennan a wealthy man.
Brennan's family had emigrated when he was nine to Australia, where he later trained as a watchmaker. It was seeing a belt-driven machine in a workshop that inspired his ideas for a "directible" torpedo.
His first prototype, unveiled when he was 25, caught the attention of the British Admiralty, which funded his development work. Ten years later it approved the system and opened a factory making "Brennans".
Brennan's guided torpedo was a coastal defence system, this being in the days before aircraft, when enemy attacks often came by sea, and torpedoes were much in vogue.
The Brennan was a sizeable missile, weighing three tonnes and carrying 100kg of explosives. The first weapon that could be guided all the way to its target, it had a range of 3km and travelled at 40kph, cruising three metres below the surface of the sea.
The guidance system consisted of two internal reels, each holding 3km of wire and each connected to one of the torpedo's two propellers. The torpedo was launched from a runway on shore, a steam-driven machine extracting the wires as the torpedo shot away.
A small mast protruding above the waves allowed the gunner to track it, steering with left- and right-hand guide wires.
Launch stations were built around the British coast, in Hong Kong, in Malta and at Fort Camden, near Crosshaven, to defend Cork Harbour. For 20 years his was the ultimate in coastal defence technology. This changed in the early 1900s with the development of new guns and other military technologies.
Brennan later designed several novel transport systems, all gyroscopically controlled. His gyroscopic monorail train (1909) was never developed, despite backing from Winston Churchill. His gyroscopically controlled helicopter (1925) achieved the first ever helicopter flight but crashed during a thankfully unmanned test run. Its failure prompted the British government to opt for a competing design.
Brennan died in 1932, before he could finish his two-wheeled gyro-car. But the tracks of the Brennan launch rail survive at Fort Camden, in Co Cork.
London's Science Museum has a small working model of Brennan's monorail train, and the Royal Engineers Museum of Military Engineering, in Kent, has the last surviving Brennan torpedo.
Louis Brennan is one of the figures featured in Ingenious Ireland (TownHouse), Mary Mulvihill's award-winning guide to Irish scientific heritage