The present disclosure relates to methods and apparatus for launch and recovery of a remote inspection device within a liquid storage tank. In one embodiment, the tank is accessed by opening an entrance hatch and then injecting a vapor suppression foam across a surface of a stored liquid mass to form a foam layer. A launching system having a remote inspection device is attached to the entrance hatch to define a launch and recovery space sealed from an external environment and isolated from the stored liquid mass in the tank via a valve and the foam layer. The launch and recovery space is purged of hazardous vapors by injection of an inert gas prior to launch and recovery of the remote inspection device. Prior to removal of the launching system, the surface of the stored liquid mass is re-coated with vapor suppression foam.

The present disclosure relates to methods and apparatus for launch and recovery of a remote inspection device within a liquid storage tank. In one embodiment, the tank is accessed by opening an entrance hatch and then injecting a vapor suppression foam across a surface of a stored liquid mass to form a foam layer. A launching system having a remote inspection device is attached to the entrance hatch to define a launch and recovery space sealed from an external environment and isolated from the stored liquid mass in the tank via a valve and the foam layer. The launch and recovery space is purged of hazardous vapors by injection of an inert gas prior to launch and recovery of the remote inspection device. Prior to removal of the launching system, the surface of the stored liquid mass is re-coated with vapor suppression foam.

An underground storage tank maintenance system includes a system of monitors to determine pressure and humidity in the system. Inert gas may be supplied into the ullage of the tank. The inert gas may first pass through an interstitial space as between the primary storage and secondary containment, and then passed into ullage to capture contaminants on the way out of the vent to atmosphere. The system and method prevent hydrocarbons exiting to atmosphere. Humidify sensors may be set along vent to determine water contamination and trigger drying cycles. Pressure readings help identify system leaks.

An underground storage tank maintenance system includes a system of monitors to determine pressure and humidity in the system. Inert gas may be supplied into the ullage of the tank. The inert gas may first pass through an interstitial space as between the primary storage and secondary containment, and then passed into ullage to capture contaminants on the way out of the vent to atmosphere. The system and method prevent hydrocarbons exiting to atmosphere. Humidify sensors may be set along vent to determine water contamination and trigger drying cycles. Pressure readings help identify system leaks.

Methods and apparatus for launch and recovery of a remote inspection device within a fluid storage tank. In one embodiment, the tank is accessed by opening an entrance hatch and then injecting a vapor suppression foam across a surface of a stored liquid mass to form a foam layer. A launching system having a remote inspection device is attached to the entrance hatch to define a launch and recovery space sealed from an external environment and isolated from the stored liquid mass in the tank via a valve and the foam layer. The launch and recovery space is purged of hazardous vapors by injection of an inert gas prior to launch and recovery of the remote inspection device. Prior to removal of the launching system, the surface of the stored liquid mass is re-coated with vapor suppression foam.

Methods and apparatus for launch and recovery of a remote inspection device within a fluid storage tank. In one embodiment, the tank is accessed by opening an entrance hatch and then injecting a vapor suppression foam across a surface of a stored liquid mass to form a foam layer. A launching system having a remote inspection device is attached to the entrance hatch to define a launch and recovery space sealed from an external environment and isolated from the stored liquid mass in the tank via a valve and the foam layer. The launch and recovery space is purged of hazardous vapors by injection of an inert gas prior to launch and recovery of the remote inspection device. Prior to removal of the launching system, the surface of the stored liquid mass is re-coated with vapor suppression foam.

Methods and apparatus for launch and recovery of a remote inspection device within a liquid storage tank are described herein. In one embodiment, the tank is accessed by opening an entrance hatch and then injecting a vapor suppression foam across a surface of a stored liquid mass to form a foam layer. A launching system having a remote inspection device is attached to the entrance hatch to define a launch and recovery space sealed from an external environment and isolated from the stored liquid mass in the tank via a valve and the foam layer. The launch and recovery space is purged of hazardous vapors by injection of an inert gas prior to launch and recovery of the remote inspection device. Prior to removal of the launching system, the surface of the stored liquid mass is re-coated with vapor suppression foam.

Methods and apparatus for launch and recovery of a remote inspection device within a liquid storage tank are described herein. In one embodiment, the tank is accessed by opening an entrance hatch and then injecting a vapor suppression foam across a surface of a stored liquid mass to form a foam layer. A launching system having a remote inspection device is attached to the entrance hatch to define a launch and recovery space sealed from an external environment and isolated from the stored liquid mass in the tank via a valve and the foam layer. The launch and recovery space is purged of hazardous vapors by injection of an inert gas prior to launch and recovery of the remote inspection device. Prior to removal of the launching system, the surface of the stored liquid mass is re-coated with vapor suppression foam.

There is provided a center fuel tank assembly for an aircraft. The assembly includes a center fuel tank disposed in a central part of the aircraft. The assembly further includes one or more fuel barrier members partitioning the center fuel tank into two or more separate volume sections comprising two or more separate sub-tanks arranged in a fore-to-aft alignment to form a partitioned center fuel tank. The assembly further includes a fuel flow control assembly coupled to each of the two or more separate sub-tanks, each fuel flow control assembly operating independently. A sequential fuel burn of fuel in the two or more separate sub-tanks is made in a fore-to-aft sequence while the aircraft is in flight, to assist in shifting aftward a center of gravity (CG) of the aircraft, to reduce aircraft drag.

Methods and apparatus for launch and recovery of a remote inspection device within a liquid storage tank. In one embodiment, the tank is accessed by opening an entrance hatch and then injecting a vapor suppression foam across a surface of a stored liquid mass to form a foam layer. A launching system having a remote inspection device is attached to the entrance hatch to define a launch and recovery space sealed from an external environment and isolated from the stored liquid mass in the tank via a valve and the foam layer. The launch and recovery space is purged of hazardous vapors by injection of an inert gas prior to launch and recovery of the remote inspection device. Prior to removal of the launching system, the surface of the stored liquid mass is re-coated with vapor suppression foam.