<p>Aircraft external fuel tanks are important components that extend the range of aircraft by storing fuel. Since structural damage to an external fuel tank during flight can have a critical impact on the survivability of the aircraft, the structural soundness of external fuel tanks considering the flight load must be verified before they are installed on aircraft. This study provides the results of a structural static test conducted to confirm the structural soundness of an external fuel tank. In the main text, the required flight loads were converted into test loads, with the accuracy of each test load confirmed by comparisons with the required flight loads. Then, whiffletree load plans were presented to conduct efficiency tests, and a test setup consisting of a test specimen, a load control system, a data acquisition system, a test fixture and hydraulic equipment was provided. From the test results, it was found that the applied test loads were appropriately controlled and the internal pressure of the test specimen was remained stably without leakage, with the deformation and strain also measured to check whether the specimen was damaged during the test. After the test, it was found that no structural damage occurred through disassembly inspection of the test specimen. Finally, it was verified that the structural soundness of the external fuel tank investigated here is sufficient for the required test conditions.</p>