Soviet reconnaissance, artillery, and Air defence

[JDR Dragoon]

The principle is still the same, whether you call it a "Reconnaisance Group" or what ever you choose to call it ;): The commander (from army to regiment) organizes a self contained combined arms detachment that can fight independently while keeping the rest of his force in reserve thus preserving freedom of maneuver. Its job is to recon (a bit) but is primary mission is to protect the unit behind it and facilitate its manuever and commitment at a decisive point in time and space. How they choose to compose the detachment depends on what its mission is, what forces are available and the overall tactical and operational stance of the unit sending out the detachment. And if the detachment itself is a large one (or tasked with a mission independently of its parent unit) it might also choose to send out a combined arms subunit in front of itself in order to facilitate its freedom of maneuver and so on. It is the principle more than the exact terminology one needs to understand.