History of the Armée de l'Air (1939-1962)

The outbreak of the war in Europe in September 1939 did not immediately affect the status of the Armée de l’Air in French Indochina because it had the task of defending a wide area of Southeast Asia, including the future Laos, Cambodia and Vietnam. And yet its array of airplanes seemed inadequate to perform any kind of real defense against any incursion by an enemy, because there were less than 100 airplanes available to it, all obsolescent or obsolete. In September 1931, Japan invaded and occupied Manchuria. This was an area of northeast China, which encompassed the provinces of Jilin, Liaoning and Heilongjiang. Nearly six whole years later, in July 1937, the Second Sino-Japanese War had begun. As yet, the French colonial authorities were hoping that the Japanese would not be brazen enough to take on the might of a European power. However, it became increasingly likely after the German invasion of Poland in September 1939, since Japan was part of the Axis alliance and thus Germany’s ally.

On September 26, 1940, Japanese troops landed in Haiphong, violating a cease-fire which had been signed only the previous day. From the middle of the following month, the French became heavily involved in repelling Japanese army assaults.

Following the Fall of France in 1940, Thais perceived a chance to regain the territories they had lost years earlier. The collapse of Metropolitan France made the French hold on Indochina tenuous. After the Japanese invasion of French Indochina in September 1940, the French were forced to allow the Japanese to set up military bases. This seemingly subservient behavior convinced the Thai regime that Vichy France would not seriously resist a confrontation with Thailand.

French forces in Indochina consisted of an army of approximately fifty thousand men, The most obvious deficiency of the French army lay in its shortage of armor; however, the Armée de l'Air had in its inventory approximately a hundred aircraft, of which around sixty could be considered first line. These consisted of thirty Potez 25 TOEs, four Farman 221s, six Potez 542s, nine Morane M.S.406s, and eight Loire 130 flying boats.

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