2011 – The first Solar Impulse aircraft, HB-SIA, the first solar-powered aircraft capable of both day and night flight thanks to its batteries charged by solar power, makes its first international flight, flying 630 km (391 miles) from Payerne Airport outside Payerne, Switzerland, to Brussels AirportinBelgium, in 12 hours 59 minutes at an average speed of 50 km/hr (31 mph).[1][2]
1992 – A U.S. Navy instructor pilot is killed after two Navy Beechcraft T-34C Turbo Mentors collide over a densely wooded field 6 miles SW of NAS Whiting Field, Florida.
1975 – (13 – 14) U. S. Navy P-3 Orion patrol aircraft discover Mayaguez off Cambodia’s Puolo Wai island. For two days, U. S. Navy and U. S. Air Force aircraft exchange fire with Khmer Rouge ground and sea forces in the vicinity of Mayaguez.
1975 – Sikorsky CH-53C, 68-10933, c/n 65-231, Knife 13, of the 21st Special Operations Squadron, departs from Nakhon Phanom Royal Thai Air Force Base with a crew of five and 18 USAF Security Police onboard to assist in the recovery operation of the SS Mayaguez. The helicopter disappears from the airfield's departure radar 40 miles W of the airfield. All on board are KWF. The Air Force issues a "temporary flight restriction" order, service parlance for a grounding order, on 22 May 1975, for 40 HH-53 and 12 CH-53, following an inspection crew reaching the jungle crash site. A main rotor blade separated from the head in flight.
1957 – Three USAF North American F-100 Super Sabres set a new world distance record for single-engine aircraft by covering the 6,710 mi (5,835 nmi, 10,805 km) distance from LondontoLos Angeles in 14 hours and 4 min. The flight was accomplished using in-flight refueling.
1955 – On seventh and final flight of Northrop N-69A test vehicle for the Northrop XSM-62 Snark, only two of which were successful, mission was cut short when the missile collided with its T-33A photo plane.
1954 – First flight of the Kellett KH-15 "Stable Mable". This helicopter was designed to test the new gyro-stabilizing system, a kind of small rotor mounted concentrically and intended to stabilize the main rotor.
1943 – 20 Japanese Mitsubishi G4 M (Allied reporting name “Betty”) torpedo bombers fly from Paramushiro to attack American ships, but bad weather forces them to turn back without launching an attack.
1940 – First flight of the Bell XFL Airabonita, United States experimental shipboard interceptor aircraft developed for the United States NavybyBell Aircraft. It was similar to and a parallel development of the land-based P-39 Airacobra, differing mainly in the use of a tailwheel undercarriage in place of the P-39's tricycle gear.
1940 – The Sikorsky VS-300, which made its first flight the previous year, makes its first untethered flight.
1938 – (13-15) A Japanese Gasuden Koken aircraft breaks the closed-circuit world distance record of 11,651 km (7,240 mi).
1912 – A Flanders Monoplanecrashed at Brooklands, Surrey, United Kingdom, killing the pilot and his passenger. The accident was investigated by the Royal Aero Club, which issued the first-ever report into an aviation accident and established the science of aviation accident investigation.