The 20th Tank Regiment was a unit of the Army of the Republic of Vietnam (ARVN), the South Vietnamese army. The 20th Tank Regiment was organized on 31 July 1971 and soon saw extensive combat during the 1972 Easter Offensive.
History
In mid 1971 I Corps, a critical area bordered by North Vietnam and Laos, was protected by ARVN infantry, three ARVN armored cavalry squadrons, and the US 1st Brigade, 5th Infantry Division (Mechanized), scheduled to leave the country in August. Analysis of terrain, the probable People's Army of Vietnam (PAVN) threat, and PAVN armored actions during Operation Lam Son 719 made it clear that armored units would continue to be needed in this area. Consequently, the South Vietnamese Joint General Staff (JGS) authorized on 31 July 1971 the formation of the 20th Tank Regiment. Equipped with M48A3 tanks, it was the first South Vietnamese tank regiment.
Tailored specifically to fit the needs and capabilities of the ARVN, the 20th Tank Regiment had an unusual organization. During Lam Son 719, armored vehicles had proven vulnerable to individual antitank weapons when not protected by infantry. The JGS had therefore directed an addition to the regiment, a 270-man armored rifle company. Ninety riflemen were assigned to each tank squadron and were to ride on the outside of the tanks, providing local security. Other changes in the tank regiment's organization and equipment included the addition of tracked M548 ammunition and fuel cargo vehicles, elimination of the regimental scout platoon, for which a five-vehicle security section was substituted, and elimination of the armored vehicle-launched bridge section and all infrared fire control equipment. Later six xenon searchlights per squadron were authorized after advisers questioned the wisdom of limiting $15 million worth of fighting equipment to daytime use by refusing to spend $300,000 on searchlights. Unfortunately, the decision to dispense with the vehicle-launched bridge section was not reconsidered, and lack of bridging during the PAVN offensive proved a major factor in the loss of tanks.
Training for the 20th Regiment began at Ái Tử Combat Base near Quảng Trị, but proceeded slowly because of many problems, particularly in maintenance. About 60 percent of the tanks received by the regiment had serious deficiencies beyond the repair capability of the tank crews. Repair parts and technical manuals were missing and the language barrier prevented US instructors from communicating adequately with the Vietnamese crewmen. On 1 November a gunnery program based on US tank standards got under way. Unfortunately, the inexperienced tank crews had difficulty in comprehending the integrated functioning of the Rangefinder and ballistic computer. Partly because of their experience with the M41 tank, which had no rangefinder, Vietnamese commanders at first could not be convinced of the rangefinder's value. Rapid troop turnover and manpower shortages also adversely affected crew performance. Training therefore made slow headway, with many reversions to basic lessons. By 25 January 1972 gunnery training ended, with 41 of 51 available crews qualifying, using test criteria as rigorous as those used for US units. Unit tactical training began in the foothills west of Quang Tri on 1 February and was judged successful in its later stages. A recurring problem during tactical testing was the Vietnamese inclination to disregard maintenance before, during, and after an operation. Continued emphasis on maintenance resulted in some improvement, but standards remained below acceptable levels, even after the unit completed its training. The regiment's final tactical test, a field training exercise, was to be conducted by the South Vietnamese Armor Command along US lines, with the proviso that any portion not completed correctly was to be repeated. Several problems delayed the exercise past its scheduled starting date of 13 March 1972. Poor weather during the gunnery phase, the necessity for some tactical retraining at the troop level, and the lack of M88 Recovery Vehicles and M548 tracked cargo vehicles to carry fuel combined to cause setbacks. Finally, after devoting several days to vehicle maintenance, the regiment began its training test on 27 March.