The intelligence report titled Airfield and Seaplane Bases in Formosa, Air Intelligence Group, Division of Naval Intelligence, Office of the Chief Naval Operations, Navy Department, June 1944, gave the coordinates of Eiko (currently Yungkang of Taian; 永康) Airfield as 23 02’N 120 14’E, which was pretty accurate during the pre-GPS era. The document said that the airfield was:
“[i]n the southwestern part of Formosa approximately 6 miles inland from the W coast. The field is 3 miles NE of the town of Tainan adjacent to and on the S side of the main road running NE from Tainan. The town of Shinka is 4 miles E of the field and Tainan Airfield is 6 miles SSW.”
A photograph of Eiko Airfield was also provided in the report. It seemed that the US military had good intelligence on this airfield at the time.
The Combat Record of Lt(jg) Edward S. Binder, Torpedo Squadron Four, on the Air Group 4 website contains the following entry:
Eiko Airfield on Formosa was hit on 4 January 1945. Binder, with Jenkins as turret gunner, carried 100-pound GP bombs in this attack.
The same website has a page titled 19. Forbidding Formosa with the following text:
“KAGI airfield was overcast and could not be located and Commander Klinsmann ordered VT to attack an airfield believed to be EIKO. VF remained as high cover during the attack and rendezvous, and escorted VT from the target area and returned as a target CAP.” … Pilots reported that the Eiko airfield appeared to be in the final stages of construction, but serviceable at the time of the strike. VT-4 planes did a good job of cratering the runways and rendering damage to airport support facilities.
A photograph of the bombed airfield was given (see below). Note that according to the text the crew believed the airfield they had attacked to be Eiko, implying that they were not absolutely certain.
Source: Air Group 4
Despite the solid intelligence the Americans had on Eiko Airfield, the airfield bombed by Torpedo Squadron Four on January 4, 1945, was NOT Eiko. Note that the pilots reported the airfield was in the final stage of construction, which could not be true because Eiko was one of the oldest airfields that the Japanese built on Formosa. You may also want to compare the above photo with the reconnaissance photo of Eiko Airdrome taken in March 1944 and you will see they are quite different.
Incidentally, the site CriticalPast also has a footage shot on January 4, 1945, which is described as “US Navy TBF Avenger bombers bomb grounded Japanese planes at Eiko airstrip, Taiwan during World War II.” At 01:10 of the film, an airfield can be seen, which does not look like Eiko but quite similar to the airfield in the above photo viewed from a different direction.
This brings us to the question: which airfield did Torpedo Squadron Four bomb on January 4, 1945?
After searching extensively over Southern Taiwan on Google Earth, I finally conclude that the above photo corresponds to the view in the following Google Earth image. The area is in Madou (referred to as Mato during WWII; 麻豆) of Tainan.
Based on the visual information in the two sources, I completed the approximate layout of Mato Airdrome and overlayed it on Google Earth. The next image corresponds to the above WII photo taken by Torpedo Squadron Four.
The following image corresponds to the still at 01:10 of the CriticalPast footage:
In the CriticalPast footage, the aircraft made a North-South pass over Mato Airdrome. After dropping the bombs, the aircraft made a wide U-turn and overflew Mato Town. At 02:13, two schools can be seen. They are currently Tseng-Wen Vocational School of Home Economics and Commercial Management (left) and Pei-Wen Elementary School (right).