Patent ID: 7648103

Claim:
An aircraft fuel tank comprising: a tank body having upper, lower and side walls which define an interior space for holding a maximum allowable volume of aircraft fuel, and a relief manifold assembly operatively mounted internally within the tank body to prevent an overpressure condition within the interior space of the fuel tank body due to an excess volume of fuel being introduced thereinto which exceeds the maximum allowable volume of fuel, wherein the relief manifold assembly includes, a buffer vessel which defines an internal buffer chamber within the tank body extending upright between the upper and lower walls of the tank body, the buffer vessel including an aperture located at a lower end thereof near the lower wall of the tank body and exposed directly to the fuel held in the interior space of the tank body, and a relief branch conduit which fluid connects the buffer chamber to a relief conduit and an associated pressure relief valve positioned externally of the tank body, the pressure relief valve having a pressure set point corresponding to the maximum allowable volume of aircraft fuel within the interior space of the tank body, wherein the aircraft fuel held in the interior space of the tank body covers the aperture of the buffer chamber so as to establish an air column under a pressure condition which increases in response to an increase of fuel volume within the interior space of the tank body, and wherein the air column achieves a maximum pressure condition corresponding to the maximum allowable fuel volume within the interior space of the tank body as determined by the pressure set point of the pressure relief valve so that additional fuel introduced into the interior space of the tank body which exceeds the maximum allowable volume of fuel will cause the pressure relief valve to operate and thereby vent the air column through the relief conduit which in turn allows a portion of the fuel held in the interior space of the tank body to enter the buffer chamber so as to relieve the maximum pressure condition of the air column therewithin and thereby prevent an overpressure condition within the interior space of the tank body.