He served as the chief of Operations Intelligence and Communications Section in the Turkish Amphibious Group Command HQ, as the chief of Operations and Training Section, and the head of Operations Directorate at the Turkish Fleet Command HQ from 1982 to 1986, and as COMEDNOREAST Administration Officer, the chief of Operations Section and the head of Command and Control Branch at the TNFC HQ between 1986 and 1989.

Karahanoğlu was promoted to rear admiral (LH) on 30 August 1990 and fulfilled his duties as the head of the Operational Training Branch from 1990 to 1993 at the TNFC HQ and as the commander of the Amphibious Ships between 1993 and 1994.

After being promoted to rear admiral (UH) in August 1994, Karahanoğlu served as the head of the Logistics Directorate (TNFC HQ), and the commander of the Surface Action Group for two years each successively.

Karahanoğlu was promoted to admiral in 2003 and assigned as the commander of the Turkish Fleet between 2003 and 2005.

He is decorated with the "Distinguished Service Medal of the Turkish Armed Forces" and the "Medal of Honor of the Turkish Armed Forces".