In Bhopal, India, lethal methyl isocyanate gas was accidentally released from a pesticides plant run by a subsidiary of Union Carbide. Between 2,500 and 5,000 people in Bhopal died on the day of the disaster, and thousands more have died since from ill-effects.

Over the Atlantic Ocean, a Boeing 747 operating as TWA Flight 800 took off from John F. Kennedy International Airport. Twelve minutes into the flight the aircraft exploded and disintegrated, killing the 230 occupants.

Mount St. Helens, a volcano in the state of Washington that had lain dormant for 123 years, began to experience seismic activity in March 1980. A series of earthquakes and small eruptions ensued as a large bulge grew in the North face of the mountain. On 18 May another earthquake caused the north face to collapse, triggering an eruption that blew off the top and side of the volcano. 57 tourists, local residents and scientists perished.

At the San Marino Grand Prix track, multiple Formula One world championship winner Ayrton Senna lost control of his car and crashed into a circuit concrete barrier wall. Senna was killed instantly.

During the Falklands War (Spanish: Guerra de las Malvinas/Guerra del Atlántico Sur), two British warships - HMS Coventry and HMS Broadsword - prepared for battle, tasked with defending the British fleet from air attack. An attack force of Argentinian aircraft bombed the Coventry and the Broadsword. One bomb hit the Broadsword but failed to explode until it had exited the ship's hull. Three bombs hit the Coventry, of which two exploded on board. The Coventry capsized shortly afterwards and sank the next day. Nineteen crew members were killed.

At the then-biannual Royal International Air Tattoo held at RAF Fairford, two Mikoyan MiG-29s flying an aerobatics routine as part of the Tattoo air display collided in mid-air. Both pilots ejected from their aircraft and survived the accident, and there were no fatalities among the spectators.