In January 1925 Janoušek was appointed Commander of the Xth Air Reconnaissance Course.
On 19 November 1925 he married Anna Steinbachová, née Hoffmannová.
On 1 January 1926 he qualified as a pilot.
He was not an outstanding pilot, but he was good at reconnaissance, air navigation and meteorology.
On 2 December 1926 he was promoted to Major of the General Staff.
In September 1927 he went on a one-month attachment to the French Armée de l'Air.
On 28 February 1928 he was promoted to Lieutenant Colonel.
By now he was Second in Command of the Military Flying School.
He co-authored a book on aerial warfare tactics, inspired by the ideas of the Italian military theorist Giulio Douhet, which was published in May 1930.

Janoušek was then posted to Slovakia and, on 31 December 1930, promoted to command the 6th Flying Regiment.
In 1930–32 his duties also included training officers to be higher commanders.
On 31 July 1933 he was promoted to full Colonel.
By 1936 he was a Brigadier General and a Provincial Commander of the Air Force.
Bad weather was a major limitation on aviation, and caused about half of all air accidents.
Therefore, in 1936 Janoušek started studying meteorology and geophysics at the Charles University in Prague.

During the Sudeten Crisis Czechoslovakia ordered a partial mobilization on 21 May and complete mobilization on 23 September.
Janoušek commanded the Air Force of General Sergei Wojciechowski's 1st Army, which was to protect the frontier with Nazi Germany from České Budějovice in the southwest to Králíky in the north.
But on 29 September France and the United Kingdom signed the Munich Agreement with Germany, forcing Czechoslovakia to cede the Sudetenland without a fight.

On 15 March 1939 Germany occupied Czechoslovakia and created the Protectorate of Bohemia and Moravia, which was required to dissolve its army and air force.
Nevertheless, Janoušek completed his course at Charles University and graduated with a doctorate in natural sciences (RNDr) on 23 June.

Hundreds of Czechoslovak army and air force personnel responded to the German occupation by escaping to Poland or France.
The secret Obrana národa Czechoslovak resistance organisation helped Janoušek to cross into Slovakia on 15 November 1939.
From there he travelled via Hungary, Yugoslavia, Greece and Beirut in French-ruled Lebanon to reach France.
In January 1925 Janoušek was appointed Commander of the Xth Air Reconnaissance Course. On 19 November 1925 he married Anna Steinbachová, née Hoffmannová. On 1 January 1926 he qualified as a pilot. He was not an outstanding pilot, but he was good at reconnaissance, air navigation and meteorology. On 2 December 1926 he was promoted to Major of the General Staff. In September 1927 he went on a one-month attachment to the French Armée de l'Air. On 28 February 1928 he was promoted to Lieutenant Colonel. By now he was Second in Command of the Military Flying School. He co-authored a book on aerial warfare tactics, inspired by the ideas of the Italian military theorist Giulio Douhet, which was published in May 1930.
Janoušek was then posted to Slovakia and, on 31 December 1930, promoted to command the 6th Flying Regiment. In 1930–32 his duties also included training officers to be higher commanders. On 31 July 1933 he was promoted to full Colonel. By 1936 he was a Brigadier General and a Provincial Commander of the Air Force. Bad weather was a major limitation on aviation, and caused about half of all air accidents. Therefore, in 1936 Janoušek started studying meteorology and geophysics at the Charles University in Prague.
During the Sudeten Crisis Czechoslovakia ordered a partial mobilization on 21 May and complete mobilization on 23 September. Janoušek commanded the Air Force of General Sergei Wojciechowski's 1st Army, which was to protect the frontier with Nazi Germany from České Budějovice in the southwest to Králíky in the north. But on 29 September France and the United Kingdom signed the Munich Agreement with Germany, forcing Czechoslovakia to cede the Sudetenland without a fight.
On 15 March 1939 Germany occupied Czechoslovakia and created the Protectorate of Bohemia and Moravia, which was required to dissolve its army and air force. Nevertheless, Janoušek completed his course at Charles University and graduated with a doctorate in natural sciences (RNDr) on 23 June.
Hundreds of Czechoslovak army and air force personnel responded to the German occupation by escaping to Poland or France. The secret Obrana národa Czechoslovak resistance organisation helped Janoušek to cross into Slovakia on 15 November 1939. From there he travelled via Hungary, Yugoslavia, Greece and Beirut in French-ruled Lebanon to reach France.
Karel Janoušek