Final answer:
The question is about the procedure of firing adjustment in a military context, specifically during a quick smoke mission using HC smoke rounds.
Step-by-step explanation:
The question refers to a procedure used in military artillery, specifically during a quick smoke mission with shell smoke (HC), which stands for Hexachloroethane, a type of smoke-producing substance. When adjusting for a target, the standard practice is to use High Explosive (HE) rounds to refine the accuracy of the fire.
The process involves finding the correct range until a certain bracket of distance, typically around 100 meters, is split. Only once the adjustments are accurate, the firing of a smoke round is requested. This serves both as a final adjustment and to mark the target with smoke.
Corrections to the fire mission are made based on the observed impact of the smoke round. Once the observer is satisfied with the target marking, a 'Fire For Effect' (FFE) is requested, which means that a full barrage of smoke rounds is called for to blanket the target area.
Observers use smoke rounds for various purposes, including screening movements, marking targets, or signaling. This question does not seem to relate to the reference provided, which concerns the firing sequence and the types of fuel used by rockets, which is a separate subject.
The observer adjusts the fire with HE rounds until a 100-meter bracket is split before requesting smoke rounds and eventually calling for 'Fire For Effect' (FFE). The provided reference about rocket fuels appears unrelated to this question.