Drones could play a key role in tracking drug runners and smugglers after successful trials with the navy's newest class of ships in the Channel.

HMS Tamar recently made extensive use of small Puma aircraft from RNAS Culdrose's 700X Naval Air Squadron, who train at Predannack airfield on the Lizard peninsula.

The ship was working with Royal Marines and the Met Police to practice 'constabulary duties' for when she deploys for the first time this summer.

Although Tamar has a flight deck, she doesn't carry a helicopter on a regular basis – there's no hangar, so Merlin and Wildcat helicopters only use the ship for refuelling, collecting supplies or making a short stop.

The Puma could fulfil some of the helicopter's intelligence-gathering role – with its 50-times zoom camera it feeds live footage back to a mother ship at ranges up to a dozen miles.

Just over 4½ft long, with a wingspan of 9ft and weighing as much as six bags of sugar, Puma can survey an area of up to 270 square miles of ocean – that's larger than Greater Manchester – looking for suspicious activity during sorties lasting up to 2½ hours.

"We were under pressure to perform," said Lieutenant Ash Loftus, Puma flight commander. "There are many additional challenges in preparing and launching safety from a ship. While it's a relatively small aircraft, it has a large wing and requires some skill from the operator launching it from the ship.

"We completed 100 per cent of the tasks required of us by the ship. We were often flying out of line of sight to approach vessels, using the system's cameras for identification purposes.

"We'd be in close communications with the officer of the watch and we were able to report back successfully on the identification of vessels."

Puma is relatively cheap – certainly much cheaper than sending a helicopter up – easy to launch and recover, is difficult for foes to spot and keeps the ship out of harm's way. In short, Puma gave Tamar 'eyes in the sky'.

"It was of great use for investigating nearby vessels of interest," said HMS Tamar's Lieutenant Commander Michael Hutchinson.

"We could easily see just how useful such a system could be for any future anti-piracy or counter-smuggling operations. It's a significant enhancement of the ship's capabilities and bodes well for the future."

Tamar and her four sisters are being deployed around the world on long-term missions, operating from overseas ports and bases, patrolling regions of key strategic interest and importance to the UK.

Constabulary duties – counter-piracy/terrorism/smuggling – are a key role of the new River-class ships.

Lieutenant Commander Justin Matthews, the commanding officer of 700X Naval Air Squadron added:

"The gauntlet was laid by the senior leadership of the Royal Navy to deliver a working, practical and operational system to the front line. Having previously deployed on exercises, we have now deployed in an operational setting, being reactive and proactive and adding to the required defence output.

"I am immensely proud of everyone on the squadron for all the hard work across many different areas which has gone into delivering this for the modern navy."