1861 - Civil War begins when Confederates fire on Fort Sumter, SC
1911 - LT Theodore Ellyson qualifies as first naval aviator
1962 - U.S. Navy demonstrates new landing craft with retractable hydrofoils, LCVP (H)
1975 - Operation Eagle Pull evacuation from Cambodia
1981 - First launching of re-useable Space Shuttle Columbia (STS-1) with all Navy crew. CAPT John W. Young, USN (Ret.) commanded, while LCDR Robert L. Crippen, USN was the pilot. Mission duration was 2 days, 6 hours, and 20 minutes. Sixteen of the shuttle's heat-shielding silicon tiles were lost and 148 damaged during reentry.
1993 - Aircraft from USS Theodore Roosevelt and NATO forces begin enforcing the no-fly zone over the Bosnia in Operation Deny Flight
1847 - Naval Forces begin 5 day battle to capture several towns in Mexico
1861 - Fort Sumter surrenders to Confederate forces
1960 - Navy's navigation satellite, Transit, placed into orbit from Cape Canaveral, FL and demonstrates ability to launch another satellite
1898 - Commissioning of first Post Civil War hospital ship, USS Solace
1969 - North Korean aircraft shoots down Navy EC-121 reconnaissance aircraft from VQ-1 over the Sea of Japan
1988 - USS Samuel B. Roberts struck Iranian mine off Qatar
1989 - First Navy ship arrives on scene to assist in Exxon Valdez oil spill cleanup
1885 - Naval forces land at Panama to protect American interests during revolution
1912 - USS Chester and USS Salem sailed from MA to assist RMS Titanic survivors
1918 - First Marine Aviation Force formed at Marine Flying Field, Miami, FL
1961 - Launching of first nuclear-powered frigate, USS Bainbridge, at Quincy, MA
1962 - USS Princeton brought first Marine helicopters to Vietnam. This was first Marine advisory unit to arrive in South Vietnam.
1986 - Operation Eldorado Canyon, Navy aircraft from USS America (CV-66) and USS Coral Sea (CV-43) attack Libya in conjunction with USAF aircraft after Libya linked to terrorist bombing of West Berlin discotheque which killed 1 American and injured 78 people.
1863 - Union gunboats pass Confederate batteries at Vicksburg
1924 - Navy commences relief operations in Mississippi Valley floods, lasting until 16 June
1947 - Act of Congress gives Navy Nurse Corps members commissioned rank
1959 - Helicopters from USS Edisto begin rescue operations in Montevideo, Uruguay. By 26 April they had carried 277 flood victims to safety.
1778 - Sloop-in-war Ranger captures British brig
1848 - U.S. Navy expedition to explore the Dead Sea and the River Jordan, commanded by LT William F. Lynch, reaches the Dead Sea.
1906 - Navy assists in relief operations during San Francisco earthquake and fire
1942 - USS Hornet launches Doolittle's Army bombers for first attack on Japan
1988 - Navy destroys 2 Iranian surveillance platforms, sinks one frigate and one patrol ships, and severely damages a second frigate in retaliation for attack on USS Samuel B. Roberts