A month later , the guided missile cruiser arrived , summoned in haste to protect the frigate '' Samuel B. Roberts '' as it was hauled back to the United States . On 3 July , '' Vincennes '' shot down Iran Air Flight 655 , killing all 290 crew and passengers . The U.S. government claimed that the crew of '' Vincennes '' mistook the Iranian Airbus for an attacking F-14 fighter , despite it being a commercial airliner flying a scheduled route . The Iranian government alleged that '' Vincennes '' knowingly shot down a civilian aircraft
Iran Air Flight 655
Iran Air Flight 655
Operation Praying Mantis