Type 23 Frigate HMS St Albans and nuclear submarine HMS Astute have faced off against each other off the Scottish coast.

“To be the best at what we do, it is essential that we train both against and alongside the very best,” Commander John Cromie, Commanding Officer of HMS St Albans, said in a news release.

“HMS Astute provides that partner with whom we can polish our skills to the highest level.”

The Royal Navy say that this latest training exercise took place in a Scottish loch and was a chance to sharpen and refine procedures necessary to coordinate activity when dealing with a potential submarine threat.

According to a Royal Navy news release:

“Type 23 frigate HMS St Albans and hunter-killer sub HMS Astute have been operating alongside each other, honing their Anti-Submarine Warfare (ASW) skills.

But it was also an opportunity for them to go up against each other, testing their ability to deal with the threat one another brings to the battlefield.”