Fuel tank tests.

CFR · 2024-01-01 · US · Title 14

(a) It must be shown by tests that the fuel tanks, as mounted in the airplane, can withstand, without failure or leakage, the more critical of the pressures resulting from the conditions specified in paragraphs (a)(1) and (2) of this section. In addition, it must be shown by either analysis or tests, that tank surfaces subjected to more critical pressures resulting from the condition of paragraphs (a)(3) and (4) of this section, are able to withstand the following pressures: (1) An internal pressure of 3.5 psi. (2) 125 percent of the maximum air pressure developed in the tank from ram effect. (3) Fluid pressures developed during maximum limit accelerations, and deflections, of the airplane with a full tank. (4) Fluid pressures developed during the most adverse combination of airplane roll and fuel load. (b) Each metallic tank with large unsupported or unstiffened flat surfaces, whose failure or deformation could cause fuel leakage, must be able to withstand the following test, or its equivalent, without leakage or excessive deformation of the tank walls: (1) Each complete tank assembly and its supports must be vibration tested while mounted to simulate the actual installation. (2) Except as specified in paragraph (b)(4) of this section, the tank assembly must be vibrated for 25 hours at an amplitude of not less than (3) The test frequency of vibration must be as follows: (i) If no frequency of vibration resulting from any r.p.m. within the normal operating range of engine spe

official document · source cfr-2024 · id 14:§ 25.965