There are many reports of having seen a news flash that a U.S. Navy nuclear-powered submarine ran aground in Tokyo Bay, but not seeing any follow-up reports afterward...
There are numerous reports from people who saw a news flash that a United States Navy nuclear submarine based in Japan ran aground in Tokyo Bay, but then never saw any follow-up, and it has taken on the feel of an urban legend.
This case is part of the Mandela Effect case database based on "The Window of Opportunity: A Guidepost to the Mandela Effect — The Ultra-Secret X-Files" by Aoyama Takuto.