Early ship movements cannot isolate the Encelia attack's effect on Saudi crude traffic

The available sequence begins before the attack. The Houthis declared their maritime blockadeblockadeA blockade is an attempt to prevent ships or cargoes from reaching or leaving specified ports or waters. on July 20, and Xin Long Yang, Rodos and Amazon changed course on July 21 while carrying Saudi crude. Vanguard reported that Encelia was struck at about 20:00 GMT on July 22. [Reuters on the blockade](https://www.investing.com/news/commodities-news/yemens-houthis-declare-naval-blockade-against-saudi-arabia--statement-4800903) [Reuters on the reversals](https://ca.marketscreener.com/news/two-tankers-carrying-saudi-crude-make-u-turns-in-red-sea-after-houthi-warning-ce7f51d8db8df624) [Reuters on the attack](https://www.internazionale.it/ultime-notizie-reuters/2026/07/23/yemen-s-houthis-say-they-targeted-two-saudi-oil-tankers)

That ordering matters. The reversals show disruption after the blockade warning, but they cannot tell us what the later projectile added. It is like measuring the effect of a second storm after drivers had already begun leaving the highway because of the first warning.

The first observations establish disruption, but not an additional strike effect.

Xin Long Yang and Cosnew Lake exited the Red Sea through Bab el-MandebBab el-MandebBab el-Mandeb is the narrow waterway between the Horn of Africa and the Middle East that connects the Red Sea with the Gulf of Aden and Arabian Sea. [US Energy Information Administration](https://www.eia.gov/international/content/analysis/special_topics/World_Oil_Transit_Chokepoints/) on July 23 carrying a combined 4 million barrels of Saudi oil bound for China. That is enough to reject one narrow claim: Saudi crude traffic through the strait had not stopped completely at that time. [Reuters](https://www.boursorama.com/bourse/actualites-amp/deux-superpetroliers-chinois-transportant-du-petrole-saoudien-quittent-la-mer-rouge-0b79445b582b6280d89e6aaacc1818c4)

It is not enough to conclude that the attack had little effect. The same Reuters report said two other UnipecUnipecUnipec is the trading arm of Sinopec and was identified by Reuters as the charterer of the two ships that crossed and the two inbound ships that slowed.-chartered VLCCs scheduled to enter the Red Sea and load at YanbuYanbuYanbu is the Saudi Red Sea port where Reuters reported the outbound cargoes were loaded and the inbound supertankers were scheduled to load. slowed toward Bab el-Mandeb and made small circles in the Gulf of Aden. Looking only at the ships that crossed would therefore omit evidence of hesitation. [Reuters](https://www.boursorama.com/bourse/actualites-amp/deux-superpetroliers-chinois-transportant-du-petrole-saoudien-quittent-la-mer-rouge-0b79445b582b6280d89e6aaacc1818c4)

LSEGLSEGLSEG is the London Stock Exchange Group, whose ship-tracking data Reuters used for the vessel movements and route-wide crossing counts in this article. counted 27 vessels crossing Bab el-Mandeb on July 22, including five oil tankers and one liquefied-petroleum-gas carrier, down from 38 total vessels on July 21. The difference is 11 vessels, or 28.9% by Cumulant's calculation. [Reuters citing LSEG](https://www.boursorama.com/bourse/actualites-amp/deux-superpetroliers-chinois-transportant-du-petrole-saoudien-quittent-la-mer-rouge-0b79445b582b6280d89e6aaacc1818c4)

AISAISThe Automatic Identification System is a radio system that broadcasts a ship's identity, position, course and speed to other ships and coastal authorities. [International Maritime Organization](https://www.imo.org/en/ourwork/safety/pages/ais.aspx) reports identity, position, course and speed. It can show that a vessel turned or crossed a strait, but it does not by itself prove what happened to the cargo at the end of the voyage. The International Maritime Organization also notes that ships ordinarily keep AIS operating except where rules allow navigational information to be protected. [International Maritime Organization](https://www.imo.org/en/ourwork/safety/pages/ais.aspx)

This distinction changes the economic interpretation. A U-turn can mean delay, rerouting or cancellation. A successful crossing can still precede a later delay. Only destination and discharge records can establish that cargo arrived and was unloaded.

Saudi authorities confirmed that Encelia was attacked, that a fire occurred at its bow and that the crew was safe. The official statement did not identify its cargo or say whether it was loaded. [Saudi Press Agency](https://www.spa.gov.sa/en/N2639825)

VesselFinder identifies Encelia as an oil-products tankeroil-products tankerAn oil-products tanker is designed to transport refined petroleum products and is a different vessel category from a very large crude carrier., while Xin Long Yang and Cosnew Lake were reported as VLCCs carrying crude. Vessel class does not reveal the exact cargo aboard on the day of an incident, but it is a warning against treating Encelia itself as evidence that a Saudi crude-export cargo was removed from traffic. [VesselFinder](https://www.vesselfinder.com/vessels/details/9240172) [Reuters](https://www.boursorama.com/bourse/actualites-amp/deux-superpetroliers-chinois-transportant-du-petrole-saoudien-quittent-la-mer-rouge-0b79445b582b6280d89e6aaacc1818c4)

A credible estimate would start with the outcome being measured: departures, loaded barrels, strait crossings, transit times or completed deliveries. It would then require a complete vessel-level record for a meaningful period before and after the attack, with consistent timestamps and cargo classifications.

The analysis would also need a counterfactualcounterfactualA counterfactual is the best evidence-based estimate of what would have happened if the event being studied had not occurred., evidence about how Saudi crude traffic would probably have changed after July 22 if Encelia had not been struck. One possible research design is difference-in-differencesdifference-in-differencesDifference-in-differences estimates an effect by comparing the before-and-after change in an affected group with the change over the same period in a credible comparison group. [World Bank DIME](https://dimewiki.worldbank.org/Difference-in-Differences), which compares the before-and-after change in an affected group with the simultaneous change in a credible comparison group. The method requires observations before and after the event and depends on the comparison group's earlier trend being sufficiently similar. [World Bank DIME](https://dimewiki.worldbank.org/Difference-in-Differences)

The reports available on July 23 do not supply that complete record or a tested comparison group. The defensible answer is therefore limited: traffic was already reacting to the blockade warning, some loaded crude still crossed after the attack, other ships hesitated, and the attack's additional effect remained unmeasured.