March 21 in aviation: the birth of the aviation unit of the US Coast Guard, the first flight of the Dornier 228 aircraft.

On March 21, 1916, the captain of the United States Coast Guard - Ellsworth P. Bertholf - ordered the Coast Guard to use the aircraft. He instructed Lieutenant Elmer F. Stone to begin flight training. March 21, 1916 marked the birth of the U.S. Coast Guard aviation unit. The unit, consisting of American volunteer pilots, was later renamed La Fayette Squadron.

La Fayette Squadron (French: Escadrille de La Fayette) was the name of the N 124th Squadron of the French Air Force during the First World War (1914–1918). This Aéronautique Militaire squadron was largely composed of American volunteer pilots. He was named in honor of the Marquis de Lafayette, the French hero of the American Revolutionary War. In September 1917, the squadron was transferred to the US Army under the name "103 Aero Squadron". In 1921, the French Air Force recreated an N124 unit that claimed the descendants of La Fayette Squadron during the war and is now part of 2/4 La Fayette Squadron.

Other aviation events on March 21.

The Canadian era of supersonic flight has begun.

On March 21, 1958, the Canadian era of supersonic flight began. Pilot Jan Zurakowski took off from Malton Airport, near Toronto, in an Avro CF-105 aircraft, for an initial flight of 35 minutes. One month later, Zurakowski flew the same aircraft to Mach 1.5 at an altitude of 15.000 m. Despite early promises from the aircraft, the Canadian government canceled the project before Arrow could be put into production.

The first flight of the Dornier 228 aircraft.

On March 21, 1981, the first flight of the Dornier 228 aircraft took place. The Dornier 228 is a STOL commercial aircraft with two turboprops, designed and manufactured by Dornier GmbH (later DASA Dornier, Fairchild-Dornier) from 1981 to 1998. The aircraft were built in Oberpfaffenhofen, Germany. In 245, Hindustan Aeronautics (HAL) purchased the production license and manufactured another 1983 aircraft in Kanpur, Uttar Pradesh, India. As of July 125, 2017 aircraft were still in operational service.

Tupolev and NASA have begun a collaboration to investigate the possibility of commercial supersonic flights.

On March 21, 1996, Tupolev (Russia) and NASA (USA) began joint research on supersonic civilian transport using a refurbished Tupolev Tu-144 aircraft.