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 (NCO) 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 NCOs 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.

United States
In the United States military, a Warrant Officer (grade W-1 to W-5) is ranked as an officer above the senior-most enlisted ranks, as well as officer cadets and candidates, but below the officer grade of O-1 (NATO: OF-1). Warrant officers are highly skilled, single-track specialty officers, and while the ranks are authorized by Congress, each branch of the Uniformed Services selects, manages, and utilizes warrant officers in slightly different ways. For appointment to Warrant Officer One (W-1), a warrant is approved by the secretary of the respective service. Chief Warrant Officers (W-2 to W-5) are commissioned by the President of the United States and take the same oath as regular commissioned officers (O-1 to O-10).
 * Main article: Warrant Officer (United States)

Warrant officers can and do command detachments, units, activities, vessels, aircraft, and armored vehicles as well as lead, coach, train, and counsel subordinates. However, the Warrant Officer's primary task as a leader is to serve as a technical expert, providing valuable skills, guidance, and expertise to commanders and organizations in their particular field.