Mitsubishi Internal Combustion Engine Company Ltd. registers as an aircraft manufacturing company, with its factory at Kobe, Japan, and takes over the aircraft manufacturing business of its parent company, Mitsubishi Heavy Industries.
British military thinker ColonelJ. F. C. Fuller writes that in the next war "Fleets of aeroplanes will attack the enemy's great industrial and governing centres. All these attacks will be made against the civil population in order to compel it to accept the will of the attacker..."
The Royal Air Force's "Z Unit" – the first self-contained air unit dedicated to "aerial policing," the use of independent air power to suppress colonial rebellions – begins operations in British Somaliland against the Dervish State of Mohammed Abdullah Hassan (the "Mad Mullah") using 10 Airco DH.9s. On the first day, a DH.9 drops a bomb on the tent of the Mullah – who has never seen an airplane before and whose advisers tell him that the aircraft must be either chariots from Allah or friendly messengers from the Ottoman Empire's Sultan Mehmed VI – while he waits to receive their crews as important guests. He survives and flees. The Z Unit will continue to bomb and strafe the Mullah's forces on January 22 and 23.
January 24 – Extensive aerial reconnaissance by the Royal Air Force's Z Unit establishes that the Dervish State has abandoned the area around its forts at Medishi (later Medistie) and Jid Ali (later Jideli). Independent air operations against the forces of Mohammed Abdullah Hassan end, and the Z Unit begins direct support to British troops pursuing Hassan.
January 29 – Royal Air Force Airco DH.9s bomb the Dervish State fort at Gallbaridur.
January 30 – Royal Air Force DH.9s bomb Mohammed Abdullah Hassan's baggage train and personal retinue, but he survives.
Early in the month, Royal Air Force Airco DH.9s bomb the Dervish State stronghold at Tale, including Mohammed Abdullah Hassan's personal compound. Hassan again survives and flees into Abyssinia. The British campaign to restore their control over British Somaliland comes to a successful conclusion in only three weeks, at a low cost in British lives and money. It is the prototype of the "aerial policing" of rebellious colonies that the Royal Air Force will conduct in the 1920s and 1930s, most notably in Iraq.
September 20 – The 1920 Schneider Trophy race is flown at Venice, Italy. Lieutenant Luigi Bolgna in a Savoia S.12 is the only starter and wins simply by finishing the race, with an average speed of 172.6 km/h (107.2 mph).
December 16 – Frank Briggs completes the first west-east or east-west crossing of Australia, between Sydney and Perth, a distance of 3,912 km (2,431 miles), in D.H. 4. (For the first south to north crossing, by Henry Wrigley and Arthur Murphy, see 1919 in aviation). Also on board were Briggs' employer, aviation entrepreneur C. J. (Jack) De Garis and mechanic Jack Howard. They left Perth in the early hours of December 13; and spent 21 hours, 38 minutes in the air (not including re-fueling).
^Scheina, Robert L., Latin America: A Naval History 1810-1987, Annapolis, Maryland: Naval Institute Press, 1987, ISBN 0-87021-295-8, p. 193.
^Scheina, Robert L., Latin America: A Naval History 1810-1987, Annapolis, Maryland: Naval Institute Press, 1987, ISBN 0-87021-295-8, p. 200.
^Francillon, René J., Japanese Aircraft of the Pacific War, Annapolis, Maryland: Naval Institute Press, 1979, ISBN 0-87021-313-X, p. 30.
^Francillon, René J., Japanese Aircraft of the Pacific War, Annapolis, Maryland: Naval Institute Press, 1979, ISBN 0-87021-313-X, p. 18.
^Francillon, René J., Japanese Aircraft of the Pacific War, Annapolis, Maryland: Naval Institute Press, 1979, ISBN 0-87021-313-X, p. 23.
^Fuller, J. F. C., Tanks in the Great War, London, 1920, p. 314, quoted in Hastings, Max, Bomber Command: Churchill's Epic Campaign - The Inside Story of the RAF's Valiant Attempt to End the War, New York: Simon & Schuster Inc., 1987, ISBN 0-671-68070-6, p. 41.
^Franks, Norman, Aircraft vs. Aircraft: The Illustrated Story of Fighter Pilot Combat From 1914 to the Present Day, London: Grub Street, 1998, ISBN 1-902304-04-7, pp. 58, 63. Franks' statement on p. 58 that Berthold was killed on December 15, 1919, appears to be incorrect.
^Layman, R.D., Before the Aircraft Carrier: The Development of Aviation Vessels 1849-1922, Annapolis, Maryland: Naval Institute Press, 1989, ISBN 0-87021-210-9, p. 122.