Sec. 23.957 - Flow between interconnected tanks.
(a) It must be impossible, in a
gravity feed system with interconnected tank outlets, for enough fuel
to flow between the tanks to cause an overflow of fuel from any tank
vent under the conditions in §23.959, except that full tanks must be
(b) If fuel can be pumped from one
tank to another in flight, the fuel tank vents and the fuel transfer
system must be designed so that no structural damage to any airplane
component can occur because of overfilling of any tank.
[Doc. No. 4080, 29 FR 17955, Dec. 18, 1964,
as amended by Amdt. 23-43, 58 FR 18972, Apr. 9, 1993]