‘Big Dippers’ hit the Bahamas as Navy's premier sub hunters hone skills

Britain’s premier submarine hunters raised the bar with an intensive three-week workout at the world’s leading underwater warfare range.

Helicopters from 820 Naval Air Squadron – charged with shielding the UK’s aircraft carrier from unwanted underwater attention – left HMS Queen Elizabeth to hone their skills on a vast range in the Bahamas.

The US Navy’s AUTEC – the Atlantic Undersea Test and Evaluation Centre – base concentrates world-leading experts and technology next to a natural wonder.

The ranges off Andros Island – south-west of Nassau – are centred on a natural phenomenon, the Tongue of the Ocean, a huge deep-water bowl carved out of coral reef, which resembles the Rolling Stones’ famous tongue logo.

It’s 20 miles wide, 150 miles long, some 6,000ft deep in places and crammed with sensors and hydrophones to record reams of data on how well a submarine, torpedo or sonar is performing.

The Merlins – based at Culdrose in Cornwall – last used AUTEC in 2008, since when the helicopter has been substantially upgraded, making it a much more potent submarine hunter.

That said, the team at the Royal Navy’s Maritime Warfare Centre at HMS Collingwood, want to develop new tactics and methods to ensure Merlin maintains its position as a world-leader in anti-submarine warfare.

With HMS Queen Elizabeth conducting fast jet trials off the east coast of the USA, the Merlins flew down from Virginia to the Bahamas where a challenging programme of tests was laid on for them as aircrew tried to hunt down unmanned underwater targets – mimicking the characteristics of real submarines.

Merlin carries sonobuoys – automated listening devices dropped across the anticipated path a submarine might take – as well as a ‘dipping’ sonar, lowered into the ocean when those sonobuoys pick up a potential contact.

Using full-colour touch-screen displays in the rear of the helicopter, the observer and aircrewman monitor the data gathered, track targets and, if necessary, attack them by launching Sting Ray torpedoes. 

Air and ground crew toiled in tropical heat – still in the 30s Celsius well into mid-November, with high levels of humidity – but were fortunately spared the usual end-of-season hurricanes (although there were bursts of monsoon-esque rain).

The trials were invaluable in ensuring that the Merlin remains a world-beating anti-submarine aircraft

Lieutenant Commander Steve Moseley

None of which prevented the helicopters getting airborne – they clocked up 60 hours of hunting and never missed one of the many tests laid on for them – especially not the combined hunt at the end of the exercise which drew in US Navy Seahawks, American aircraft, maritime patrol aircraft and real submarines. 

‘AUTEC is a fantastic opportunity to really put the aircraft through its paces,” said 820 Squadron’s senior pilot Lieutenant Commander Steve Moseley.

“The excellent facilities are perfect for allowing the aircrew to really push the sensors to their limits and understand how best to operate the systems to detect, track and ultimately attack targets in a wide range of underwater conditions.

“The trials were invaluable in ensuring that the Merlin remains a world-beating anti-submarine aircraft and, in concert with the technical expertise of our colleagues from the Maritime Warfare Centre, we are able to ensure that it continues to be for many years to come.”

It wasn’t all work for the crews – small groups left the base to explore the island’s famous blue holes – geological features perfectly designed for sailors to jump in, despite threats of a mythical ‘Sharktopus’ sea monster lurking in the depths – and show off the impressive mosquito bites for which Andros is infamous. 

“The tactical trials have been a huge success. The Merlin Mk2 has proven it possesses a world-leading anti-submarine warfare capability,” said Commander Russell Clark, senior carrier strike/aviation staff officer at the Maritime Warfare Centre.

“The first-class support from 820 Naval Air Squadron’s aircrew and engineers resulted in a successful series of trials and period of tactical development.” 

The Merlins and supporting personnel have now returned to HMS Queen Elizabeth as she continues her F-35 trials.