In Biggles Follows On, Kungching was described as an international marine aircraft establishment in South Korea where servicing facilities were available as well as an R.A.F. maintenance unit. It presumably served the marine aircraft of the United Nations forces participating in the Korean War. Biggles chose Kungching as the jump off point for his operation to rescue Guardsman Ian Ross from Kratsen since he was using a marine aircraft type, the Scorpion flying boat.
Kungching is a fictional location. There was no international marine aircraft base during the Korean War. Neither is there a town named Kungching in Korea. During the Korean War, R.A.F. Sunderlands used the base at Iwakuni, Japan. Within Korea, where the marine aircraft were amphibians, these would normally put down at airbases on land. There were some reports of marine aircraft using Inchon during the Korean War. Inchon, a port near the capital Seoul, is also near the border with North Korea and as such was probably the best equipped facility near to Chinese territory. This would have made Inchon a good jump off point for Biggles.