Warrant officer

A warrant officer (WO) is an officer in a military organization who is designated an officer by a warrant, as distinguished from a commissioned officer who is designated an officer by a commission, or from non-commissioned officer who is designated an officer by virtue of seniority.

The rank was first used in the (then) English Royal Navy and is today used in many other countries, including the Commonwealth nations, and the United States. Outside the United States they are effectively senior non-commissioned officers with long military experience, although technically in a cadre of their own between non-commissioned officers and commissioned officers. Warrant officer is a rank between flight sergeant and pilot officer in the Royal Air Force.

However, warrant officers in the United States are technical leaders and specialists, and chief warrant officers are commissioned by the president of the United States and take the same oath as regular commissioned officers. They may be technical experts with long service or direct entrants, notably for U.S. Army helicopter pilots.