14 CFR 29.957 - Flow between interconnected tanks.
(a) Where tank outlets are interconnected and allow fuel to flow between them due to gravity or flight accelerations, it must be impossible for fuel to flow between tanks in quantities great enough to cause overflow from the tank vent in any sustained flight condition.
(1) The design of the vents and the fuel transfer system must prevent structural damage to tanks from overfilling; and
Title 14 published on 2015-01-01.
No entries appear in the Federal Register after this date, for 14 CFR Part 29.