Great Hormuz escape: 80% of traffic goes ‘dark’ as US flips Iran’s playbook

DUBAI: Something extraordinary is happening in the Strait of Hormuz.

Tankers carrying millions of barrels of Gulf crude are effectively disappearing from public view as they approach the world’s most important oil chokepoint — only to reappear hours later on the other side.

They are not missing. They are deliberately going “dark”.

About 80 per cent of traffic through Hormuz over the past two weeks has been operating this way, according to shipping analytics firm Kpler. Tankers are switching off their Automatic Identification System (AIS) transponders and travelling close to Oman, as far from Iran as possible.

Behind many of these journeys is the US military, which is helping protect vessels moving through a southern corridor of the strait.

The remarkable result is that a largely invisible shipping operation is helping keep Gulf oil flowing — and preventing an already severe energy crisis from sending crude prices dramatically higher.

A tanker disappears

The journey of the Greek-owned supertanker Kiku shows how the system works.

After loading crude at Qatar’s Mesaieed terminal, the giant tanker crossed Hormuz and was sailing off Dubai on July 31 when its AIS signal suddenly disappeared.

At 10am the next day, Kiku reappeared — on the other side of Hormuz.

It had made what has become known as a “dark” transit, part of a system of nighttime crossings supported by the US military and designed to reduce the danger from Iranian drone attacks.

The strategy goes beyond simply getting tankers through Hormuz.

Gulf oil companies have chartered vessels that shuttle crude through the strait before transferring their cargo to other tankers waiting in the Gulf of Oman. Those vessels then carry the oil onwards to customers around the world.

Hormuz’s invisible oil highway

• 80% Share of Hormuz traffic estimated to have gone “dark” over the past two weeks.

• 8–9 million barrels/day Estimated oil traffic through Hormuz, according to the US Department of Energy.

• 5 million barrels/day Crude carried out of the Arabian Gulf on US-protected routes in July, according to analysts.

• 1,000+ ships Vessels the US military says it has helped transit the strait.

• 15 ships Vessels using southern routes hit since the beginning of June, according to a New York Times analysis.

• 1.9 billion barrels Amount by which oil inventories may have been depleted during the war.

There is a striking irony to the tactic. For years, Iran has relied on a so-called “dark fleet” — tankers switching off or manipulating tracking signals and using ship-to-ship transfers — to keep its oil moving despite US sanctions.

Now, some of those same methods are being turned against Tehran: Gulf oil is moving through Hormuz aboard vessels that disappear from tracking screens before re-emerging beyond the strait, in many cases under US military protection.

The difference is in the purpose — rather than evading sanctions, the “dark” runs are designed to reduce exposure to Iranian attacks and keep global oil supplies flowing.

CNN observed more than a dozen such ship-to-ship transfers over two days, with oil subsequently heading towards China, Taiwan, South Korea, the Philippines, Vietnam and Thailand.

The oil market can’t see everything

Turning off AIS creates another striking consequence: Conventional ship-tracking data can substantially underestimate how much oil is actually passing through Hormuz.

The US Department of Energy estimates oil traffic through the strait has averaged between 8 million and 9 million barrels a day — roughly double what some Wall Street analysts and tracking services relying on transponder data would suggest.

Satellite and radar imagery provides clues to the missing traffic.

Images from August 14 showed vessels around the Omani side of Hormuz that did not appear in MarineTraffic data at the same time — ships that were physically there but electronically invisible.

Why this matters for oil prices

Before the war, around 15 million barrels of crude passed through Hormuz every day. In July, tankers using US-protected routes alone carried about 5 million barrels a day out of the Arabian Gulf, according to analysts cited by The New York Times.

That additional supply matters enormously.

The war has disrupted a major share of global oil supply and depleted commercial inventories. Yet the feared complete shutdown of Hormuz has not materialised.

Instead, producers and traders have repeatedly found ways around the disruption.

Saudi Arabia has rerouted about 5 million barrels a day through its East-West pipeline to the Red Sea port of Yanbu. Another roughly 2 million barrels a day has been rerouted around Hormuz, while Brazil, Guyana and Venezuela together have added more than 1 million barrels a day of production. US output has also increased.

Together with the “dark” Hormuz crossings, these measures have helped prevent the supply shock from translating into the kind of explosive oil-price surge once feared.

But America is paying a price

Keeping the southern corridor operating is neither simple nor cheap.

US Central Command uses ships, helicopters and aircraft, along with weapons capable of intercepting Iranian drones and missiles. More than 1,000 ships have been helped through the strait, according to Central Command.

And the protection is far from impregnable.

At least 15 ships using southern routes have been hit since the beginning of June, according to a New York Times analysis of International Maritime Organization data. Iran also retains the ability to intensify attacks against shipping and Gulf energy infrastructure.

The US military faces another problem: Endurance.

With its Bahrain naval base effectively destroyed by Iranian attacks, Navy supply ships now have to travel to Diego Garcia in the Indian Ocean, a journey taking more than five days each way.

Around 20 US warships are operating in the Gulf of Oman, while maintaining carrier and destroyer deployments over an extended period is becoming increasingly difficult.

A workaround, not a solution

The invisible fleet has therefore bought the oil market something precious: time.

But it cannot permanently replace a freely navigable Strait of Hormuz.

Oil inventories have already been depleted by as much as 1.9 billion barrels during the war. If those reserves continue falling, there could eventually come a point when supply can no longer meet demand without substantially higher prices.

For now, however, one of the strangest consequences of the Hormuz crisis is also one of the most important.

Ships are disappearing from tracking screens precisely so their oil can keep appearing on the world market.