Audio Warnings From U.S. Navy Illustrate Chaotic Communication Driving Unprecedented Blockade -- WSJ
By Rebecca Feng, Daniel Kiss and Jason French On the afternoon of April 13, seafarers in the Persian Gulf and the Gulf of Oman heard a stern warning broadcast over marine radio, the primary tool for voice communication between ships. The audio marked the beginning of a monthslong American naval blockade, now in its second iteration, that has redirected more than 270 vessels as of Oct. 5 and disabled or destroyed almost two dozen more, according to U.S. Central Command. The U.S. has spent billions of dollars on naval operations related to the Iran war, including to maintain a presence of about 20 Navy ships to enforce the blockade of vessels the U.S. thought to have stopped at Iranian ports. No known tanker carrying Iranian crude oil has slipped past the U.S. blockade line since July, ship trackers say, cementing the effort as one of the most effective ways to cut off Iran's oil revenue and damage its economy. It has proved more effective than years of international sanctions in stopping Iran from selling oil. The operation has involved days and nights of chaotic communication between oil tankers' crew members -- some of whom don't speak or understand English -- and the U.S. Nav
By Rebecca Feng, Daniel Kiss and Jason French On the afternoon of April 13, seafarers in the Persian Gulf and the Gulf of Oman heard a stern warning broadcast over marine radio, the primary tool for voice communication between ships. The audio marked the beginning of a monthslong American naval blockade, now in its second iteration, that has redirected more than 270 vessels as of Oct. S. Central Command.
S. S. thought to have stopped at Iranian ports. S.
blockade line since July, ship trackers say, cementing the effort as one of the most effective ways to cut off Iran's oil revenue and damage its economy. It has proved more effective than years of international sanctions in stopping Iran from selling oil. S. Navy, according to dozens of audio recordings reviewed by The Wall Street Journal.
The audio recordings, shared by mariners in the region, illustrate how the blockade has been imposed and bring to life the experiences of civilian seafarers navigating the unprecedented geopolitical tension in the Middle East. S. blockade outraged Tehran, which lashed out by attacking commercial ships. In the days that followed, Iran's Sepah navy -- a special-operations unit under the command of the Islamic Revolutionary Guard Corps -- issued warnings to mariners, seeking to impose its influence.
On April 18, Sanmar Herald, an Indian-flagged oil supertanker loaded with two million barrels of Iraqi crude, was hit by the Iranian navy on its way out of the strait heading to India. On the radio, seafarers nearby heard the shaking voice of the captain trying to contact the Iranian navy. K. Maritime Trade Operations.
The attack caused no injuries among the tanker's crew. Sanmar Herald turned back after the attack but eventually exited the strait in June, according to ship tracker Kpler. It sailed dark on the way out, meaning it didn't publicly broadcast its location. Sailing dark On May 6, the USS Abraham Lincoln aircraft carrier disabled an Iranian-flagged oil tanker, Hasna, by firing several rounds from a 20 mm cannon gun, according to Centcom.
Hasna wasn't carrying oil at the time. The ship had been sailing dark for more than a year. S. Navy is generally able to find such ships by flying aircraft overhead and launching unmanned systems in the water -- in addition to its ships being equipped with advanced radar and intelligence systems.
The attack forced Hasna to issue a distress call and publicly reveal its position off the coast of Sohar, Oman. Hasna's rudder was disabled, Centcom said in a press release. The tanker was recently anchored just north of Iran's Larak island, according to data from Kpler. S.
naval blockade was conducted professionally. "Vessels that refuse to comply with blockade enforcement, receive multiple warnings, with ample opportunity to comply," she said. S. Navy gave Lavine -- a Mozambique-flagged, 36-year-old sanctioned liquefied-petroleum-gas tanker -- 15 minutes to clear its crew from the engine room.
S. was calling. Over marine radio, they tried to figure it out. Lavine was crewed by 28 Indian seafarers at the time, according to the Embassy of India in Tehran.
It wasn't clear what cargo it was carrying at the time of the attack, but the ship has been sanctioned in the past for aiding the Houthi rebels. Like most dark vessels, Lavine changed its name several times and spoofed its Automatic Identification System, or AIS, signals. Shadow tankers often appear to run across land or be in locations inconsistent with their recent track. S.
warning, Lavine, which identified itself by a former name of Disha, issued a distress call on marine radio. No nearby ships offered to help. The next day, Centcom posted on social media that it disabled the ship after the crew attempted to violate the blockade several times and ignored repeated warnings. It is no longer transiting to Iran, Centcom said.
Pleading for help Other times, help was offered. On Aug. S. Navy.
On marine radio, the captain of nearby vessel Courtesy K talked to the captain of Vela Nova and told him that Courtesy K would approach and circle Vela Nova to pick up and rescue its crew members. Centcom later that day told Courtesy K's flag state, the Republic of the Marshall Islands, that salvage operations of Vela Nova were being arranged by Centcom, according to Andreas G. Kokkinos, manager director of Courtesy K's manager Kast Management. Authorities told Courtesy K its help wasn't needed, and the vessel continued its journey, Kokkinos said.
S. warnings in English. S. Navy aircraft delivered a warning to Panama-flagged bulk carrier Liao Fan, which Centcom suggested had made a stop at the Iranian port Bandar Abbas.
E. port just outside the strait. Liao Fan seemed stuck in a Catch-22 situation. S.
but, lacking permission from Tehran to return to an Iranian port, he also risked being hit by Iranian forces. S. said. "Turn back now, brother.
This is not the time to call the shipowner. S. really will fire on you," one said in Chinese. S.
ended up not attacking Liao Fan. The ship eventually managed to get past the blockade line and is now off the coast of Malaysia, according to ship trackers. It was unclear how Liao Fan managed to evade the blockade, but it is possible it unloaded Iranian-linked goods. S.
Navy not to fire. S. Navy not to fire on them. Both vessels were anchored off the Iranian coast, not moving, according to maritime security firm Vanguard.
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