Macourek joined the Royal Hungarian Mounted Artillery Division No. 1 in 1914. After two years on the ground, he volunteered for the air service and completed observer training in December 1916. He was assigned to Flik 23 on the Isonzo front and scored his first victory flying a Hansa-Brandenburg C.I. In 1917, having completed pilot school, he joined Flik 6 on the Albanian front in October and scored two victories flying a Berg (Aviatik D.I). Macourek assumed command of Flik 1J at the end of July 1918 and after scoring two more victories, he finished the war as an ace. Post-war he flew for the Red Air Corps, became a citizen of Hungary and changed his surname to Maklary. Macourek was awarded the Hungarian Order of the Brave and, in 1931, the Gold Bravery Medal for Officers.