• During a standoff involving a Royal Navy frigate, an oil tanker, and three Iranian gunboats on Wednesday, the British warship HMS Montrose trained its deck guns on the Iranian vessels, CNN first reported, citing US and UK officials.
  • The HMS Montrose is armed with two automated rapid-fire 30 mm deck guns specifically designed to incapacitate or destroy small fast-moving watercraft like Iranian gunboats.
  • A retired US Navy captain with a great deal of experience dealing with the Iranians said the 30 mm guns on the Royal Navy’s frigates are the “perfect weapon” for dealing with their gunboats.
  • The Iranian gunboats, which the UK government has accused of trying to seize the BP oil tanker British Heritage, backed away after receiving verbal warnings from the frigate escorting the tanker.
  • Visit Business Insider’s homepage for more stories.

When three Iranian gunboats attempted to seize a British oil tanker on Wednesday, a Royal Navy frigate intervened, reportedly taking aim at Iranian vessels with the “perfect weapon” while warning their crews to stand down.

The Royal Navy frigate HMS Montrose positioned itself between the tanker and the approaching Islamic Revolutionary Guard Corps (IRGC) vessels and trained its deck guns on the gunboats, CNN reported, adding that the Montrose is equipped with two 30 mm guns designed to repel small fast-moving watercraft.

Read more: Iranian gunboats trying to seize a British oil tanker were scared away by the Royal Navy

“The fact that it was military ships, the IRGC in this case, creates a certain level of tension. It moves the confrontation from a maritime safety issue into a security issue,” the retired US Navy Capt. Rick Hoffman told INSIDER.

The Iranians withdrew without the situation escalating further.

Hoffman, who frequently came in contact with Iranians while commanding frigates and cruisers in the Middle East, said the Royal Navy frigate was armed with guns ideal for targeting the Iranian gunboats.

Lees ook op Business Insider

“They are the perfect weapon,” he said of the 30 mm guns on the Montrose. “It has a high volume of fire, a high rate of fire, and it has a lethal kinetic projectile. I don’t have to hit that thing with many of those before the vessel is incapacitated or destroyed.”

The British Type 23, or Duke-class, frigates are equipped with hard-hitting DS30M Mark 2 Automated Small Calibre Gun systems, which consist of a 30 mm Mark 44 Bushmaster II cannon on an automated mount. The guns can fire off a couple hundred rounds per minute at ranges in excess 2 nautical miles.

The Royal Navy began refitting its frigates with these weapons a little over a decade ago as part of the littoral Defensive Anti-Surface Warfare upgrade.

“We don’t know the British rules of engagement,” Hoffman told Business Insider. “If the commander felt there was a risk of a military action by those vessels, under rules of engagement that we have experienced in the past, they may very well have had the authority to open fire. And they have a huge advantage.”

At range, the ship with this weapon has a “substantial advantage,” he said. As the Iranian vessels close in, something they can do while the British vessel determines intent, the threats posed by these boats increases. Regardless, these small craft are going to be outgunned.

“They’ve got to come through that spray of fire with some sense of resolution,” Hoffman said.

The HMS Montrose also sent out a helicopter, an AgustaWestland AW159 Wildcat that circled the Iranian gunboats, while the British warship issued warnings to the Iranian commandos before they departed, according to US and UK officials.

Iran has denied impeding the British oil tanker, the BP vessel British Heritage, saying that if it really wanted to seize this ship, it would have. The standoff in the Strait of Hormuz was filmed by a US air asset, but the US military has yet to release the video footage.