In 1932, Rojas was called to the front lines in order to defend the country in the war against Perú.
The following year he was assigned to Buenaventura's port as commander of the Coast Battery and military engineer of the region in case of a Peruvian attack.
In 1936, he became an engineer of the technical department of the Colombian Army, ammunitions factory, on behalf of which he was sent on a special mission to Germany to obtain the machinery necessary to make ammunitions in Bogotá.
On his return to Colombia he was nominated as chief of the technical department of the munitions factory.

In 1943, he was sent to the United States to acquire weapons and other machinery for the Colombian military.
In 1944, he became assistant director of the School of War, and in 1945 the director of Civil Aeronautics.
It was there where he presented his project for airports in Colombia under the name "Tracks of landing in Colombia," which served as a dissertation for his promotion to colonel of the Army, a plan which he would subsequently bring into being with the El Dorado Airport and other airports during his later presidency.

In 1946, now a colonel, Rojas was nominated as commander of the First Brigade in Tunja and in 1948 was named commander of the Third Brigade in Cali.
There, he gained major recognition in the country for having managed to appease the rebellion that happened in this region as a consequence of the assassination of the popular leader Jorge Eliécer Gaitán on April 9, 1948, for which he was honoured by the incumbent Conservative President Mariano Ospina Pérez.
On October 11, 1949, he was promoted to General and on October 19 assigned to the Central Command of the Army.
In 1932, Rojas was called to the front lines in order to defend the country in the war against Perú. The following year he was assigned to Buenaventura's port as commander of the Coast Battery and military engineer of the region in case of a Peruvian attack. In 1936, he became an engineer of the technical department of the Colombian Army, ammunitions factory, on behalf of which he was sent on a special mission to Germany to obtain the machinery necessary to make ammunitions in Bogotá. On his return to Colombia he was nominated as chief of the technical department of the munitions factory.
In 1943, he was sent to the United States to acquire weapons and other machinery for the Colombian military. In 1944, he became assistant director of the School of War, and in 1945 the director of Civil Aeronautics. It was there where he presented his project for airports in Colombia under the name "Tracks of landing in Colombia," which served as a dissertation for his promotion to colonel of the Army, a plan which he would subsequently bring into being with the El Dorado Airport and other airports during his later presidency.
In 1946, now a colonel, Rojas was nominated as commander of the First Brigade in Tunja and in 1948 was named commander of the Third Brigade in Cali. There, he gained major recognition in the country for having managed to appease the rebellion that happened in this region as a consequence of the assassination of the popular leader Jorge Eliécer Gaitán on April 9, 1948, for which he was honoured by the incumbent Conservative President Mariano Ospina Pérez. On October 11, 1949, he was promoted to General and on October 19 assigned to the Central Command of the Army.
Gustavo Rojas Pinilla