Based on the Coast Guard Historian’s timeline, https://www.history.uscg.mil/research/chronology/
With inspiration from Mike Kelso

December 11

1881  Six men landed from a boat on Race Point, Cape Cod, and were soon after found, wet, chilled, and much exhausted, by the patrolman from Station No. 6, Second District.  He learned that they were the captain and crew of the Canadian schooner J .A. Hatfield that had been sunk in a collision with an unknown bark the previous night.  The patrolman conducted them to the light keeper’s dwelling nearby.

United States Coast Guard Cutter Mellon (WHEC-717) makes way through the Bering Sea while acting as search and rescue standby cutter for the Bering Sea Opilio Crab fishery. U.S. Coast Guard photograph 010209-C-6130A-500, PA1 Keith Alholm

2014  CGC Mellon returned to Seattle following a seven-week deployment in the Eastern Pacific Ocean after interdicting nearly 700 pounds of cocaine seized from seagoing drug smugglers.  The drugs, recovered during a single bust off the coast of Central America, were worth an estimated street value of $18.6 million.  Three suspects were detained during the operation. The more than 150-person crew of Mellon left Seattle on October 25 to conduct anti-narcotics and search and rescue missions along the coast of Mexico and Central America.  Their efforts resulted in six law enforcement boardings and the disruption of an additional 1,900 pounds of cocaine shipments headed for the U.S.  Just as Mellon began its journey homeward on November 24, 2014, the cutter was diverted to lead search and rescue operations in the case of a missing U.S. sailor.  The sailing vessel Seven Sisters was found capsized off the coast of Mexico with no crew present after the vessel was reported as overdue to the port of Acapulco.  Over the course of nearly a week, Mellon launched its attached MH-65 Dolphin helicopter and crew up to four times a day and covered more than 26,000 square miles of ocean while searching for the lost sailor.  Extra lookout watches were set aboard the cutter in hopes of finding him, but the case was suspended after the search efforts proved unsuccessful.  Another search and rescue operation involved a few unlikely survivors.  About 300 miles off the coast of Guatemala, Mellon’s crew spotted four sea turtles and a dolphin entangled in more than 100 feet of abandoned fishing line.  A small crew launched one of the small boats to rescue the animals and remove the debris from the water.  After nearly an hour of cutting the animals free, they were released and appeared to be uninjured.

December 12

1876  The first ever examination for Revenue Cutter cadets was held in Washington, D.C.

The 82-foot patrol boats of Squadron One (RONONE) deploying from Subic Bay in the Philippines to the theater of operations in Vietnam. (U.S. Coast Guard)

1965  Division 13, Coast Guard Squadron One (RONONE) was established for service in Vietnam. This third division of 9 WPBs, which would be based at Cat Lo, brought the squadron up to 26 WPBs with Division 11, 9 WPBs based at An Thoi Naval Base, Phu Quoc Island, and Division 12 based at Da Nang.

By U.S. Navy – United States Naval Operations Vietnam, Highlights; June 1966 – Map – U.S. MARKET TIME Forces, Public Domain, https://commons.wikimedia.org/w/index.php?curid=34475896

1994  CGC Munro responded to a mayday from the Greek-registered 798-foot container ship Hyundai Seattle approximately 550 nautical miles south of Adak, Alaska.  The freighter reported an engine room fire that left the ship dead in the water.  An HH-65 attached to the cutter hoisted 27 crewmen to safety.  The freighter was later towed safely into Seattle.