Operations of U.S. Army Chemical Mortar Battalions

by Bruce Elliott for Rodney Young, 20 February 2016


As I understand your question, you’re interested in CMB operations and functions above the company level. For some of my answer, I’ll quote or refer to the item, “Command and Control in U.S. Army Chemical Mortar Battalions” that I wrote and sent you last March 28. I don’t want to load you with duplicate material but some seems appropriate here in order that I cover the present subject well in stand-alone fashion.


First, a pertinent note about the line companies of a battalion (A, B, C in a triangular organization). Those companies were each the lowest level (smallest) units that had complete control and responsibility for all their assigned personnel: food, clothing, equipment, weapons, ammunition, fuel, training, operations, maintenance, general supply, health, payroll, discipline, morale, welfare, and just about anything else you can think of. All of it for 24 hours a day, every day of the year. Of course, the battalion staff and HQ Co provided backup for much of this, plus a higher level of command and control, and one important function that companies did not have: intelligence.


CMBs, like other combat battalions in the Army, had a CO who was a lieutenant colonel, and a staff consisting of the following. An executive officer (major), a sergeant major (master sergeant), and four primary staff officers: S1 - personnel and administration, a captain; S2 - intelligence, a captain; S3 - operations, a major; and S4 - supply and logistics, a captain. Each of those staff officers obviously had at least a few people helping them with the task. The S4 had lots of people and vehicles to keep the troops supplied with food, fuel, weapons, ammunition, equipment, clothing, and so on.


The original intent for CMBs was that they each operate as a unified battalion firing missions under the operational control of the battalion commander and staff. But it never happened that way, in either WWII or Korea. Companies themselves nearly always operated as single integrated units, each one attached to a different infantry regiment or division which directly controlled the CMB company’s operations and supplied it with intelligence. Very rarely were a company’s platoons split off and attached separately to different infantry units; they weren’t organized or equipped to support themselves.


As a result, important parts of the CMB staff were little used, despite original plans. There was plenty of need for the S1 and S4 to provide their support for the line companies, but in combat operations the S2 and S3 were definitely underutilized because their functions were supplied to the line companies by the infantry units they were attached to.


The Bn CO, S2 and S3 were normally in constant close contact with their counterparts in the unit (division, corps or field army) to which the battalion was assigned or attached. The CO, and sometimes the S3, tried in addition to maintain some degree of contact with the mortar companies of their battalion, but this was often very difficult because of the physical distances between companies and their frequent displacement in fluid situations.


The maximum range of the 4.2" mortar was only 4,400 yards. In combat operations, a mortar company’s FDC and firing platoons were thus always very close to the infantry’s front line. The company rear (service and support elements) was typically many miles behind the line. The battalion rear in turn was normally even further back, with its S1 and S4 functions being furnished directly to the rear elements of each company.