Rikhye served as part of UN Peace Keeping force and as a military adviser to the United Nations Secretary-General Dag Hammarskjöld and U Thant in the 1960s.

He served with the 6th Duke of Connaught's Own Lancers (Watson's Horse) during World War II.

As military advisor, he was responsible for operations in the Democratic Republic of the Congo, Rwanda, Burundi, West Irian, Yemen, and Cyprus.

While waiting for evacuation to occur, UNEF came under fire during beginning of Six-Day War.

[8] From 1970 to 1990, he was president of the International Peace Academy,[9] a New York-based organization that promotes the settlement of armed conflicts by training negotiators, diplomats and military personnel in peacekeeping.