Text Box:  78th Field Artillery (Radar), 13th Combat Aviation Battalion, 1st Aviation Brigade

Soc Trang and Can Tho, Vietnam


Author: Dwight Staehler, Vietnam 1967-68


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The 78th Field Artillery Detachment was one of many small Target Acquisition Radar units stationed around Vietnam . According to some accounts there were about 50 different FA Radar Detachments in the country. Apparently, the detachment number designations had no regimental affiliation and were chosen in part because they were not in use by other units on either the active or inactive rolls of the Army.  Staffing usually consisted of a Warrant Officer, a Sergeant (Section Chief), and five Specialists (a radar mechanic/technician and four operators).  At times there might be additional personnel undergoing orientation as replacements.


The 78th was newly constituted on 14 April 1965 along with the 76th, 77th, and 79th Artillery detachments.  It activated at Ft. Hood on 20 April 1965 and arrived in Vietnam in August.  It was in-country until it inactivated on 31 March1972.


Our Set was an AN/MPQ-4A Counter Mortar Radar trailer-mounted on a raised platform to clear the surrounding structures. It was powered by a 7.5 KW motor generator placed underneath. The detachable control console was in the duty room of our barracks. It utilized an analog computer to determine the launch coordinates of ballistic munitions.


The radar design was found to have two shortcomings.  First, the monitored sector, 25 degrees, was narrow.  The enemy could observe the parked antenna position and choose an off-sector launch site.  Countermeasures included deploying multiple radars for better coverage and optically screening the antenna.  Second, the radar was designed to track high-angle, ballistic-trajectory targets and not low-angle propelled rockets.


During my tour from March 1967 to March 1968, The 78th FA Det was located within the LY-THUONG_KIET ARVN compound and under the command of 13th Aviation Battalion (Combat) “Guardian” of the 1st Aviation Brigade. We were situated northeast of the Airfield and close to the city of Soc Trang (Kanh Hung), in the Mekong Delta (IV Corps). That vantage point provided the best coverage of Viet Cong launch sights. The radar installation was no longer operable after the Tet offensive in February of 1968, so the Personnel were recalled to the air base. A replacement radar set was obtained and the unit was moved to Can Tho in May.


The SocTrang Airbase was originally a Japanese airfield during their WWII occupation of Indo China


Text Box:

Within my time period, when the unit was based at Soc Trang, the following personnel rotated through the group: (* indicates multiple tours in Nam)


            Commanding - MOS 211AO      

                        WO Strumsky *

                        WO Worley


            Section Chief - MOS 17B4O

                        SSGT Moore *

            Technicians – MOS 26B3O

                        SP5 Nelson

                        SP5 Schoolmaster *

                        SP5 Staehler

            Operators – MOS 17B2O

                        SP4 Boots

                        SP4 Burzynski

                        SP4 Edwards

                        SP4 Hilsinger

                        SP4 Irwin

                        SP4 Martinez

                        SP4 Reeves

                        SP4 Thrower

                        SP4 Walters

                        SP4 West

                        SP4 Young




AN/MPQ4-A Counter Mortar Radar Specifications:



            Maximum        = 10,000 meter (6.2 miles)

            Accuracy         = +/- 10 Meters

            Resolution       = 50 meters


            Coverage        = 445 mil (25 degrees) fixed sector

            Accuracy         = +/- 1.5 mils


            Frequency       = 16,000 mc (Ku Band)

            Peak Power    = 50 KW

            Rep Rate         = 8,600 cps

            Pulse Width    = 0.25 microseconds

Power Unit

            Type                            Motor driven, PU304

            Output                         208/120 Volts, 400 cps, Wye connected, 3 phase

            Fuel consumption       2.15 gallons per hour