1540: Joao Torto, in Viseu, Portugal, builds two pairs of cloth-covered wings, an upper and lower, which are connected by iron hoops. While preparing to jump from the town’s cathedral to the nearby St. Matthew’s fields, he is killed when the elaborated helmet slips over his eyes and he falls onto a roof.

1897: Percy Pilcher is towed about 750 feet in the Hawk, the fourth of his hang gliders.

1951: The first flight of aircraft with variable-sweep wings is made as the research aircraft Bell X-5, flies for 30 minutes at Edwards, California.

1972: Airline pilots hold a worldwide strike, calling for tighter security.

1983: First flight of Bombardier Dash 8.

1995: First flight of Boeing 767-300F.

2011: Robert H. Widmer passes away. A designer of military aircraft that was renowned for his stubborn advocacy of revolutionary over incremental changes in aviation design. He worked for Consolidated Vultee, Convair, General Dynamics, Lockheed and Lockheed Martin. His designs include the PBY Catalina, The B-24 Liberator, The B-32 Dominator, The B-36 Peacemaker, the B-58 Hustler, the F-111, the F-16 Fighting Falcon and the Tomahawk Cruise Missile.