Ukrainian People's Army
Volodymyr studied at the Nepliuyevsky cadet corps and later at Mikhailov Artillery Academy in Orenburg, Russia. After short service at the head of an artillery detachment went to study at the prestigious Artillery Academy of the General Staff along with Oleksander Hrekov with whom he joined the General Staff (General Bulawa) of the Ukrainian People's Army. After graduation with distinction went to serve at different positions in St.Petersburg — served as staff officer and aide-de-camp. Throughout his career Sinclair mostly served as a staff-officer.