The Tadpoles of Korea

By Don Skinner

The outbreak of war in Korea in 1950 quickly brought the realization that although the Fifth Air Force and the Far Eastern Air Forces (FEAF) had tactical air units available, it had no tactical air control elements. The United States Air Force (USAF) possessed only one tactical air control group, the 502nd at Pope AFB, North Carolina. Movement of this unit to the Korean theater of operations was requested by FEAF on 28 July, 1950.

Also requested at the same time were three detachments equipped with electronic ground-directed bombing equipment from the 3903rd Radar Bomb Scoring (RBS) Squadron. These elements began moving in August, 1950.

Arriving in Korea in September, these three units, designated as Detachments C, K, and N, were attached to the 502nd Tactical Control Group (Tac Con Grp) which by now had established a presence in Korea. These RBS units were tasked with ground-directed bombing of enemy units.
The equipment the detachments possessed was van-mounted radar and control units. The radars were slightly modified SCR-584 types that had been developed as gun-laying radar in World War II. The control vans contained various analog computers and a plotting surface centrally located that allowed radar data to be displayed in reference to an aircraft’s movement over the ground. A map could be affixed, and an inking system drew a line that corresponded to the aircraft’s movement. With this system, the units could direct an aircraft to the coordinates of a selected target and give bombing instructions. Officially, the equipment bore the military nomenclature MPQ-2.

Detachments C and K moved northward and established positions at Pyongyang, North Korea in November. Here, they directed bombing mission against troop concentrations. When the Chinese forces intervened, and the United Nations forces were compelled to retreat, Detachments C and K moved south to Taegu in January, 1951. Here, they were joined by Detachment N from Pusan.

Detachments C, K, and N were redesignated as Detachments 11, 5, and 22, respectively, with one being assigned to the G/3 (Air-Ground) section of each Army Corps operating in Korea. In keeping with the chain of administrative control, and to separate them from the three Aircraft Control and Warning (AC&W) squadrons now operating in the 502nd Tac Con Grp, they were designated as Tactical Air Direction Post (TADP), from whence came the sobriquet “Tadpole.”

There is a minor controversy in the explanation of how these units acquired the name “Tadpole.” Military men have always sought to reduce acronyms to speakable words. In this desire for clarity, “GP” became “Jeep.” A common recipient of this action was early radar equipment for which the TPS-type radars were spoken of as “Tipsy” and CPS-types were acknowledged as “Cepus.” Equipment later used by Tadpoles, the MSQ series, bore the designation “Mis-Cue.”

The initials TADP only would seem to be a natural for this process. However, there are claims that the detachments were spoken of in communiqués and messages as being “Operating Locations.” In this case, the designation would be TADP (OL.) What would follow seems only natural. Regardless of the origin of the name, personnel at these bomb-directing units proudly claimed the name of Tadpoles.

At the same time the 3903rd RBS sent the detachments, the 1st Shoran Beacon Squadron sent a unit to Korea. The use of Short Range Navigation (Shoran) had enabled bombers and photographic planes to be directed to targets in Italy during World War II. However, the results in Korea were far from satisfactory. The war planners gave all ground-directed bombing missions to the Tadpoles.

By March, 1951, the Tadpoles were conducting night bombing raids against enemy positions using mostly B-29 aircraft. In addition, the three detachments moved north behind advancing troops, placing themselves closer to the front lines and enabling wider use of their capabilities in directing tactical air. One of these units, Detachment 11 (radio call sign “Hillbilly”) took up a position across the Imjin River, north of Seoul. Detachment 5 (“Beverage”) was placed near Chunchon while Detachment 22 (“Chestnut”) was east of Wonsan.

In a typical mission, the aircraft would be directed by one of the three major radar sites into a specified area, where the MPQ-2 equipment would lock-on with its automatic tracking radar. The assistant controller would make radio contact with the aircraft and after authenticating with the code of the day, obtain bomb load, fusing, altitude, air speed, and wind aloft information. These factors were used to determine which of several pre-selected targets best suited the ordnance carried by the aircraft.

From a list of targets furnished by the G-3 section and pre-selected targets designated on the plotting board, the controller selected the target. Utilizing information received from the aircraft, the attack was planned. Bomb tables containing release factors were consulted, and a release distance was calculated. The target was plotted on the board, the release distance set in, and the controller then would guide the aircraft to the pre-determined point by radio commands. When the aircraft was on the proper heading and at the proper distance, a count-down was used to release the bombs. Any strike information such as secondary explosions or fires were relayed to the Tadpole which logged all aspects of the mission and reported them to various headquarter units the next day.

By July, the 3903rd RBS personnel were in the process of being recalled to the United States. The Tadpoles now came under the command of the three AC&W Squadrons and were partially manned by personnel from these units. The 606th AC&W Sqdn took “Beverage,” the 607th took “Chestnut,” and the 6132nd as the newly-designated 608th took control of “Hillbilly.” Also, by October, new equipment designated MSQ-1 was brought in, and most detachments now had double capability. The MSQ-1 utilized a highly modified SCR-584 type radar, but the control van had a new design. The plotting board was now vertical and encased in a desk-type piece of equipment with analog computers in sealed units on each side. In addition, a bank of ground to air radios and recording equipment was placed in the van.

However, the MSQ-1 required more elaborate set-up procedures for a mission than did the MPQ-2. Maintenance and calibration procedures were different, so maintenance and control personnel had to adjust to these conditions. In November, the controller at “Hillbilly,” while setting up target coordinates, did not properly complete the routine. As a result, the B-29 under control was vectored wrong and dropped its bomb load on the detachment. Fortunately, only slight damage was done to equipment, and no personnel were injured.

In February, 1952, “Beverage” sent its MPQ-2 north to the vicinity of Kumwha, leaving the MSQ-1 in position at Chunchon. The position at Kumwha became active in late February, and by March was fully involved in close support missions.

With ground-directed bombing firmly established, a controversy arose between air and ground officers as to the proper targets. Combat units wanted close air support, day or night, down to hitting individual artillery positions. Air officers insisted the better use of the system was against troop concentrations and supply depots. An examination of surveillance and photographic missions showed the Circular Error Probable (CEP) or the smallest circle likely to be hit accurately was approximately 1200 feet with B-26 aircraft and 1300 feet with B-29s. There was an agreement between Army and USAF headquarters that the MPQ-2 and MSQ-1 missions would be directed against large concentrations such as marshalling yards, supply depots, and troop staging areas. Highway and railway bridges, a favorite target in the opening campaigns, were virtually non-existent at this time.

By May, two new MSQ-1 units with trained officer s were supporting air operations for I and X Corps. The new computer system was faster and more accurate than that used by the MPQ-2. As the theater of operations moved north, the mountainous terrain had a diminishing effect on the range of the radars. However, due to placement near the front lines, the accuracy of the system was still evident.

After June, weather conditions mandated use of the Tadpoles in a close support role. During the months of June and July, with cloud conditions prohibiting free air assaults, the three detachments controlled more than 2,000 bombing runs against enemy front line positions, dropping a combined 4,000 tons of bombs from both B-26 and B-29 aircraft in mostly night missions.

With the war becoming a static front fight, and peace negotiations dragging on, the Tadpoles continued to do the job they were called upon to do. By the cessation of hostilities in June, 1953, the Tadpoles had proven the value of ground-directed bombing. Regardless of the equipment used, or the units which manned them, the Tadpoles wrote their own chapter in the book of the Korean War.

Note: The author was a “Tadpole”, serving in radar maintenance and as assistant controller at “Hillbilly” from 1 Sept – 4 Dec, 1951. He then served at “Beverage”, serving at Chunchon and then at Kumwha until May, 1952 when he returned to the U.S. after an extended tour that included duty with the 6132nd AC&W Squadron, detached service to 7th Infantry Division G-3 as a forward air controller, and subsequent service as a “Tadpole.”