Exercise Deep Blue

Exercise Deep Blue

After a ten day work-up on-board HMS Illustrious around the Cornish coast, the Merlin Carrier Air Group (MCAG) prepare to “Go Deep” as they sail westwards out into the Atlantic in pursuit of Submarines.


Exercise Deep Blue has so far seen the Merlin Mk 2s from Royal Naval Air Station Culdrose put through their paces in the South West Approaches, exercising and practicing before they get a sniff at a live target.

That will come as they move westwards where they expect to find UK and Dutch submarines trying to penetrate their tight anti-submarine shield around HMS Illustrious and the two Type 23 Frigates who are joining the Task Group for the exercise.

“We have nine Merlins Mk 2s onboard,” said Commander Ross Spooner, CO of 820 NAS and Commander of the MCAG. “What we anticipate to deliver throughout this exercise is protection for the Fleet. Three aircraft will be in the air at any one time, two of them on station 24 hours a day.”

The role of the Merlins is to keep the Submarines away from the Carrier. High tech sonobouys are dropped in the water at intervals to form a barrier or screen to detect the enemy.

The aircraft also has a dipping sonar to “Ping” a signal out and listen to returns should a adversary get near to the Task Group. Torpedoes and Depth Charges can then be deployed to persecute and destroy the targets.

Aircrews and Engineers work to punishing schedules to keep the momentum up. Pilots, Observers and Aircrewmen work a “Sleep – Eat – Fly – Sleep” rotation, constantly planning the next stage of the routine with little concept of the 24 hour clock.

Engineers work an eight hour watch system that allows them to carry out maintenance on the Merlins which are not in the air or waiting to go onto the flying programme, either on deck or in the Ship’s large but crowded hangar.

“The primary role of the Merlin is ASW,” (Anti-Submarine Warfare) said Lieutenant Alex Best, an Observer with 820 NAS. “Upgrades to technology on-board have made this a phenomenal aircraft that is the best Sub Hunter in the world.”

All this is a hair’s breadth away to when HMS Queen Elizabeth begins operating with the Fleet and the skills and routines practiced today will be vital to the ship’s defence.

“The day to day business of ASW is something we have always practiced,” continued CDR Ross Spooner.

“What we are doing here is refreshing the pace and tempo, getting ourselves back onto the deck with large numbers of aircraft and large numbers of people, making sure we can maintain those 24/7 operations.”

Press Release, June 17, 2014; Image: UK Navy