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. 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 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).
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.
That guy really knows is stuff, to be that technically and tactically competent, he must be a Chief Warrant Officer.