ARLINGTON, Va. — The U.S. Navy has issued a formal notice that it is setting a standoff distance of 100 meters for other ships approaching its vessels — and the sea service is warning armed adversaries that it could consider crossing that line as a threat.
In a May 20 “notice to mariners” broadcast to shipping, the Navy said that “due to recent events, in order to enhance safety, minimize ambiguity and reduce opportunities for miscalculation, all vessels are advised to maintain a safe distance of at least 100 meters from U.S. naval vessels in international waters/straits.
“Armed vessels approaching within 100 meters of a U.S. naval vessel may be interpreted as a threat and subject to lawful defensive measures.”
The maritime area affected by the notice includes the Arabian Sea, the Gulf of Oman and the Persian Gulf.
The formal notice was published following incidents near the Strait of Hormuz on April 15, when 11 Iranian navy (IRGCN) armed small craft “repeatedly conducted dangerous and harassing approaches of the USS Lewis B. Puller, USS Paul Hamilton, USS Firebolt, USS Sirocco, USCGC Wrangell and USCGC Maui while the U.S. vessels were conducting joint integration operations with U.S. Army AH-64E Apache attack helicopters in the international waters of the North Arabian Gulf,” the U.S. 5th Fleet said in a release.
“The IRGCN vessels repeatedly crossed the bows and sterns of the U.S. vessels at extremely close range and high speeds, including multiple crossings of the Puller with a 50-yard closest point of approach and within 10 yards of Maui’s bow,” the release added.
“The U.S. crews issued multiple warnings via bridge-to-bridge radio, five short blasts from the ships’ horns and long-range acoustic noise maker devices but received no response from the IRGCN. After approximately one hour, the IRGCN vessels responded to the bridge-to-bridge radio queries, then maneuvered away from the U.S. ships and opened distance between them.”
The Iranians occasionally have used their highly maneuverable boats in swarms to harass naval and merchant ships in the Persian Gulf and last year captured merchant ships flagged in the United Kingdom and other nations.
Many U.S. ships are armed with Mk38 25 mm chain guns and M2 .50-caliber machine guns — in addition to larger-caliber guns on some ships — for countering fast attack craft, while many helicopters based on American ships are armed with Hellfire and Advanced Precision Kill Weapon System guided missiles that are effective against such craft.
In January 2016, Iranian boats seized two U.S. Navy riverine command boats and detained the crews after the U.S. boats strayed into Iranian waters off Farsi Island in the Persian Gulf. The crews and boats later were released.
The notice also said that “mariners are reminded to operate in accordance within international law and with due regard for the safe navigation of other vessels. All vessels operating in the vicinity of U.S. naval vessels are advised to clearly communicate intentions, respond to queries concerning course and speed, exercise principles of prudent seamanship required under international and remain at maximum distance from U.S. naval forces.”