Dark AIS Operations Test Resilience of Hormuz Oil Supply Chains
Crude exports through the Strait of Hormuz are continuing after attacks on individual vessels, but the flow now depends on a more complex and less transparent operating model. Tankers are disabling AIS, grouping movements into convoys and using ship-to-ship transfers to reduce exposure in the strategic chokepoint.
The shift illustrates a broader Industry 5.0 challenge: digital systems can only support resilient decision-making when the data layer remains trustworthy. Between 16 and 23 September, maritime analysis recorded 55 AIS-visible transits. That was approximately 94% below the pre-conflict benchmark of about 910 weekly movements, but the apparent collapse cannot be read as a direct measure of actual traffic. Deliberate tracking blackouts are part of the operating response.
Resilience through more handovers
The emerging system uses large crude carriers as a shuttle service. They enter the Gulf with AIS inactive, transfer cargo in the Gulf of Oman and return through the Strait. The crude can then be divided among Suezmax tankers for onward delivery. From a security perspective, this limits the number of vessels required to make the higher-risk crossing. From an industrial-systems perspective, it adds interfaces, manual coordination points and opportunities for discrepancies between physical movements and digital records.
Between 20 and 22 September, an estimated 26.72 million barrels of crude exited the Gulf through the Strait. Around two-thirds was later moved through ship-to-ship transfers. The equivalent rate was approximately 8.9 million barrels per day, although this was a convoy-driven peak rather than evidence of a stable export rhythm.
Planning with incomplete operational data
Iran has demanded that vessels use the northern corridor through its territorial waters. Growing Saudi, Iraqi and Kuwaiti volumes, together with some UAE exports, are taking the southern corridor, which remains supported by US air-defence and naval assets. Saudi loadings at Gulf terminals recovered to an estimated 3.9 million barrels per day during the first 27 days of September. Tracked cargoes were mainly bound for China and India, with some routed through transfer areas off Fujairah and Oman.
For industrial companies in the UK and Europe, the practical consequences extend beyond maritime security. Voyage-management platforms must distinguish intentional AIS silence from delays, anchorage periods or technical failures. Planners also face less certainty over cargo custody, insurance exposure and available tanker capacity. The additional transfers may improve short-term continuity, but they do not remove systemic risk: another attack or escalation could quickly disrupt routing, freight availability and regional fuel supplies.
