<P> Sergeant First Class is a military rank in some militaries and other uniformed organizations around the world, typically that of a senior non-commissioned officer . </P> <P> Sergeant First Class (SFC) is the seventh enlisted rank (E-7) in the U.S. Army, ranking above staff sergeant (E-6) and below master sergeant and first sergeant (E-8), and is the first non-commissioned officer rank designated as a senior non-commissioned officer (SNCO). </P> <P> A sergeant first class is typically assigned as a platoon sergeant at the company level or battalion operations non-commissioned officer in charge at the battalion level, but may also hold other positions depending on the type of unit . In a combat arms role, a sergeant first class is typically in charge of from 18 soldiers and four tanks in an armor platoon to 40 soldiers in a rifle platoon . A sergeant first class' primary responsibilities are tactical logistics, tactical casualty evacuations, and serving as the senior tactical adviser to the platoon leader . Sergeant first class replaced the rank of technical sergeant in 1948 . (However, the U.S. Air Force, which separated from the Army in 1947, retained the rank of technical sergeant and the U.S. Marine Corps had the rank of technical sergeant until 1959). </P> <P> A sergeant first class is addressed as "sergeant" except in certain situations, such as field artillery units, in which a sergeant first class serving as platoon sergeant is commonly referred to as "Smoke". If a sergeant first class is appointed to fill the role of first sergeant, he or she is addressed as "First Sergeant". Typically a sergeant first class assigned on a manning document to fill a first sergeant role while being promotable to master sergeant can be frocked to first sergeant rank and hold the insignia due its position . </P>

What does a sfc do in the army