Mortar support units

Fighting in Italy was as bitter and the enemy defenses as stubborn as any experienced by American forces in World War II. The mountainous Italian terrain, with its abundance of defiladed positions inaccessible to artillery fire, placed a heavy demand on high trajectory weapons, particularly the 4.2-inch mortar. In addition, 4.2-inch mortar units were indispensable to Ranger and Commando units which lacked organic heavy weapons. Most infantry commanders were at first unaware of the potential of the 4.2-inch mortar, but once they had seen the weapon in action they were usually anxious for mortar support. In Italy the chemical mortar truly came of age. 

Maizieres-les-Metz fell on 30 October, and the all-out drive on the city of Metz began early in November. As at Aachen, the attack took the form of a double envelopment, each arm of which was supported by companies of the ist Battalion. In this operation Company C found itself attached to Team Cherry of the toth Armored Division, a most unusual arrangement. During the initial stages of the attachment mine fields and roadblocks kept the advance at a relatively slow pace, and the mortar company was able to assume its normal role. But as the pace quickened, the problems of the supporting unit increased.. In order to insure constant support, the two mortar platoons leapfrogged forward, one of them ready to fire while the other advanced to the next appropriate position. A liaison officer stayed with the team commander to insure prompt response to any calls for fire. This leap-... 

Unless otherwise noted, material for this section was based on the after action reports and unit filea of the Sad Chemical Mortar Battalion and supported units. The latter include XIV Corps, 4 d, 37th and ztth Divisions, iSad and 24th RCT s, and i3Sth Field Artilleiy Battalion. These records may be found in the Sixth Army Reds, CMLHO. Military Intelligence Division, War Department, World War II, A Chronology, and CWS Theater of Operations Letters, 7, 10, it, 19, have also been used. 

The elements of Reckless Task Force had chemical mortar support for the Hollandia operation, but this support came from a rather odd source. Because of a shortage of mortar units in the zone of interior the War Department in February 1944 authorized the SWPA to convert a tank destroyer battalion to a chemical mortar battalion at the earliest practicable date. Almost immediately the theater reorganized the 641st Tank Destroyer Battalion which, after a brief period of training, participated in the Hollandia operation, under command of Lt. Col. Alexander Batlin. But redesignation waited until Jime 1944, producing the anomalous situation of a so-called tank destroyer unit firing 4.2-inch chemical mortars. ... 

The performance of the 4.2-inch mortars on Leyte was not an unqualified success. Infantrymen frequently complained that the mortar units could not keep pace with them in rapid advances over rough terrain, a situation resulting as much from the rainy season in which the operation took place as from the lack of complete organic transportation among the mortar units. This lack stemmed directly from the infantry s unfamiliarity with the needs of mortar units—only one of the six divisions which saw action had had previous chemical mortar support. As a result, most of them failed to allot sufficient shipping... 

The thermostatic mortar P, whose function is described below, is a small electrical heating unit (1 5 cm. in diameter and 7 cm. long) kept constant at 180 . The temperature is kept constant by another Simmerstat. The mortal may be supported on its Simmerstat box or alternatively screwed on to the end of the furnace, a gap of 1 cm. being left between the furnace and the mortar in each case. The right-hand end of the mortar bore is only wide enough to take the drawn-out beak end of the combustion tube, which is thus held in place. 

In the early 1980s, the corrosion of structural steel supports due to chloride ions liberated from PVDC-modified mortar which had been used to repair an old brick building, led to a civil suit in the United States l l therefore, PVDC latex is not currently used as a cement modifier in the United States and other countries. In a laboratory study, the liberation of chloride ions is observed in such a chloride-containing polymer, and a possibility of the conosion of the reinforcing bars which is induced by the chloride ions in reinforced concrete structures is suggested.l H The use of PVDC-modified mortars with polymer-cement ratios of 5% or more causes the liberation of sufficient chloride ions to exceed flie tolerable corrosion limits for the reinforcing bars in reinforced concrete structure. 

FUSA Chemical Section, devoted maximum attention to supply and to the needs of the chemical mortar battalions. It also meant the provision of supply support and tactical advice for the smoke generator units which were heavily employed by TUSA, especially in its river crossings. As a result of experience in these tasks, the TUSA Chemical Section found that the one chemical depot company attached could not handle all supply requirements. It recommended that two such companies be assigned, and more important still, that CWS should have far more transportation for the depot company, the smoke generator, and the mortar units. The CWS could not operate its own supply system, which it did with very little help from other supply services, and at the same time shift men and equipment in a fast-moving war without greatly Increased transportation. The chemical section suggested addition of a truck company to the Army for CWS... 

Theater commanders, with a few exceptions, willingly supported the preparedness effort since they valued the insurance. They increasingly welcomed the CWS nongas warfare activities as the war progressed. They had no heavy mortar other than the chemical mortar, which proved tremendously effective, and they had no means for sustained provision of artificial smoke other than the smoke generator units and CWS-furnished smoke pots and ammunition. 

The answer to the basic tactical question from the American point of view was to mount an overwhelmingly superior force, which would mean using all the men in every combat-ready unit which could be assembled in the United Kingdom and which could be provided with transport to the Continent, The technical services in turn would have to accumulate sufficient materiel to support such a force. The CWS ETO portion of the materiel project involved three basic categories of supply (i) individual and collective gas warfare protective and decontaminating items for the entire force (2) weapons and ammunition for chemical mortar units plus flame and smoke weapons and equipment for all combat forces (3) and special operational requirements such as smoke protection for the beachhead. The first job was... 

---