The UAS is catapulted off the back of ships and then recovered by flying them back to be caught by a wire extended over the side. It is expected to be used shortly to spot pirates threatening shipping in the Indian Ocean.
Details emerged as Defence Secretary Philip Hammond threw open the RAF’s secret base for controversial drones – RAF Waddington in Lincolnshire.
RAF crews here and at the USAF base in Creech, Nevada, fly the Reaper on surveillance and attack missions over Afghanistan.
The 35ft long remotely piloted air system can unleash weapons on insurgents with the trigger being pulled thousands of miles away.
In 54,000 hours of flying over Afghanistan it has fired 459 weapons, usually Hellfire missiles in support of Coalition troops under attack from insurgents.