During battle to the north of Sliven, Georgi Drazhev was captured by the Turks and hanged on 29 June 1876, but Kovachev managed to escape the gallows.

[1] On 7 March 1884 he was promoted to captain, and in the spring of 1885 his company was sent to the Rhodope Mountains to the south of Pazardzhik to protect the Bulgarian population from Turk and Greek bands.

In the beginning of the First Balkan War he was in command of the 2nd infantry division and the Rodopi Detachment which advanced in the secondary direction from Plovdiv to Western Thrace.

[1] On 14 July 1913 General Kovachev was appointed Minister of Defense in the new government of Stoyan Danev but due to the tense situation he remained in the front lines.

Due to his disapproval of the action of Tsar Ferdinand and the beginning of the Second Balkan War he was removed from office and from command of the 4th Army and on 27 August 1913 went to the reserve.

[1] After Bulgaria entered the First World War in 1915, Stiliyan Kovachev was mobilized in the headquarters of the 2nd divisional region and from 1916 he became head of the Main Rear Command of the army.