Abstract: A method for predicting a quantity of a contaminant in a fuel tank at the end of a time period, the method comprising the steps of: determining a quantity of the contaminant in the fuel tank at the start of the time period; determining at least one operating condition of the fuel tank during the time period; using information relating to the at least one operating condition of the fuel tank to generate a predicted quantity of the contaminant accumulated in the fuel tank during the time period; and calculating, based upon the quantity of the contaminant at the start of the time period and the predicted quantity of the contaminant accumulated during the time period, a predicted quantity of the contaminant at the end of a time period.

Abstract: An aircraft fuel tank ventilation system, comprising a refrigerative dehumidifying device having a refrigerating element in contact with air flowing between a vent open to the atmosphere and a fuel tank. Also, a method of dehumidifying air introduced into an aircraft fuel tank via the ventilation system, the method comprising directing atmospheric air from the vent into contact with the refrigerating element, and cooling the refrigerating element so as to remove water vapor from the air flowing from the vent towards the fuel tank by condensation.

Abstract: A fuel system includes a fuel tank, a vent tank fluidically connected to the fuel tank ullage, the vent tank having a duct open to the ambient atmosphere and the interior of the vent tank, and a catalyst disposed in the duct, wherein the catalyst is adapted to deplete one or more reactive components of gas flowing through the duct by catalytic reaction. Also, a method for depleting one or more reactive components of gas in the fuel system, includes depleting one or more reactive components of gas flowing through the duct using the catalyst.

Abstract: A conduit protection system, comprising: a conduit for carrying a fluid; a sealed vessel surrounding the conduit along a protected zone of the conduit; and a valve moveable between a first position for obstructing fluid flow through the protected zone of the conduit and a second position for enabling fluid flow through the protected zone of the conduit, wherein the valve is biased to the first position, and wherein the valve is fluidically coupled to the sealed vessel such that a positive pressure within the sealed vessel is operable to move the valve to the second position against the bias. Also, a method for protecting a fluid carrying conduit.

Abstract: An aircraft having a dihedral wing configuration with a wing fuel tank and a vent system for ventilating the fuel tank, the vent system including a combined vent-surge tank disposed inboard of at least part of the wing fuel tank, a vent fluidically connecting the vent-surge tank to ambient, and a vent line fluidically connecting the upper part of the fuel tank to the combined vent-surge tank, wherein the vent line has its lowest point at the combined vent-surge tank.

Abstract: A fuel system comprising a fuel tank, a vent tank having a duct open to the ambient atmosphere, a first vent line fluidically connecting the fuel tank ullage to the vent tank, a gas drying system including a pump and a dehumidifying device disposed within the vent tank, and a second vent line fluidically connecting a dry gas outlet of the dehumidifying device to the ullage, wherein the pump is operable to maintain a higher pressure within the ullage than in the vent tank so as to drive vapor rich gas from the ullage into the vent tank via the first vent line. Also, a method of operating the fuel system and a method of retro-fitting the gas drying system in an existing fuel system. The gas drying system may optionally be a gas drying/inerting system.

Abstract: An aircraft fuel system including a fuel line for carrying liquid fuel, and a microwave energy transmitter for energizing water carried in the fuel line. Also, a method of suppressing ice formation in an aircraft fuel system, the fuel system including a fuel line carrying liquid fuel, and a microwave energy transmitter, the method comprising transmitting microwaves along the fuel line to energize water carried with the fuel in the fuel line.

Abstract: An aircraft fuel tank ventilation system includes a dehumidifying device disposed in flow communication between a vent open to the atmosphere and a fuel tank. A method of dehumidifying air introduced into an aircraft fuel tank via a ventilation system includes directing atmospheric air through a dehumidifying device disposed in flow communication between a vent of the ventilation system and the fuel tank, which removes water vapor from the air flowing from the vent towards the fuel tank. A method of regenerating a desiccant medium used to dehumidify air introduced into an aircraft fuel tank via a ventilation system includes directing air through the desiccant medium so as to dry the desiccant medium.

Abstract: A data transmission network comprising: a base comprising: a base light source and a base light detector; a plurality of nodes, each node comprising a node light source and a node light detector; and a plurality of optical fibers arranged to form a optical fiber network. Each optical fiber is arranged to receive light from the base light source, transmit the light received from the base light source to one or more of the node light detectors via an air gap, receive light from one or more of the node light sources via an air gap, and transmit the light received from the node light source(s) towards the base light detector.

Abstract: An aircraft fuel tank ventilation system, comprising a desiccative dehumidifying device including a desiccant medium disposed in flow communication between a vent open to the atmosphere and a fuel tank, and a microwave energy transmitter for energizing liquid water in the desiccant medium to facilitate regeneration of the medium. Also, a method of regenerating a desiccant medium of a dehumidifying device of an aircraft fuel tank ventilation system, the method comprising directing air through the desiccant medium, and transmitting microwave energy into the desiccant medium for energizing liquid water in the desiccant medium to facilitate regeneration of the medium.

Abstract: A fuel system comprising a fuel tank, a vent tank having a duct open to the ambient atmosphere, a first vent line fluidically connecting the fuel tank ullage to the vent tank, a gas drying system including a pump and a dehumidifying device disposed within the vent tank, and a second vent line fluidically connecting a dry gas outlet of the dehumidifying device to the ullage, wherein the pump is operable to maintain a higher pressure within the ullage than in the vent tank so as to drive vapour rich gas from the ullage into the vent tank via the first vent line. Also, a method of operating the fuel system and a method of retro-fitting the gas drying system in an existing fuel system. The gas drying system may optionally be a gas drying/inerting system.

Abstract: A fuel system comprising a liquid fuel tank, an engine, and a coalescing filter adapted to separate water from fuel, the filter having an inlet fluidically connected to the fuel tank, a first outlet fluidically connected to a fuel feed system for the engine, and a second outlet fluidically connected to the fuel tank, wherein the coalescing filter is adapted to discharge fuel filtrate from the second outlet and filtrand from the first outlet. Also, a method of removing water or ice from a fuel tank, the method comprising directing a flow of fuel from a fuel tank to a coalescing filter adapted to separate water from fuel, discharging filtrand from a first outlet of the coalescing filter to a fuel feed system for consumption by an engine, and discharging fuel filtrate from a second outlet of the coalescing filter and returning the fuel filtrate to the fuel tank.

Abstract: A conduit protection system, comprising: a conduit for carrying a fluid; a sealed vessel surrounding the conduit along a protected zone of the conduit; and a valve moveable between a first position for obstructing fluid flow through the protected zone of the conduit and a second position for enabling fluid flow through the protected zone of the conduit, wherein the valve is biased to the first position, and wherein the valve is fluidically coupled to the sealed vessel such that a positive pressure within the sealed vessel is operable to move the valve to the second position against the bias. Also, a method for protecting a fluid carrying conduit.

Abstract: A data transmission network comprising: a base comprising: a base light source and a base light detector; a plurality of nodes, each node comprising a node light source and a node light detector; and a plurality of optical fibres arranged to form a optical fibre network. Each optical fibre is arranged to receive light from the base light source, transmit the light received from the base light source to one or more of the node light detectors via an air gap, receive light from one or more of the node light sources via an air gap, and transmit the light received from the node light source(s) towards the base light detector.

Abstract: An aircraft fuel tank ventilation system includes a dehumidifying device disposed in flow communication between a vent open to the atmosphere and a fuel tank. A method of dehumidifying air introduced into an aircraft fuel tank via a ventilation system includes directing atmospheric air through a dehumidifying device disposed in flow communication between a vent of the ventilation system and the fuel tank, which removes water vapour from the air flowing from the vent towards the fuel tank. A method of regenerating a desiccant medium used to dehumidify air introduced into an aircraft fuel tank via a ventilation system includes directing air through the desiccant medium so as to dry the desiccant medium.

Abstract: An aircraft fuel tank ventilation system, comprising a refrigerative dehumidifying device having a refrigerating element in contact with air flowing between a vent open to the atmosphere and a fuel tank. Also, a method of dehumidifying air introduced into an aircraft fuel tank via the ventilation system, the method comprising directing atmospheric air from the vent into contact with the refrigerating element, and cooling the refrigerating element so as to remove water vapour from the air flowing from the vent towards the fuel tank by condensation. An aircraft fuel tank ventilation system, comprising a refrigerative dehumidifying device having a refrigerating element in contact with air flowing between a vent open to the atmosphere and a fuel tank.

Abstract: An aircraft having a dihedral wing configuration with a wing fuel tank and a vent system for ventilating the fuel tank, the vent system comprising: a combined vent-surge tank disposed inboard of at least part of the wing fuel tank; a vent fluidically connecting the combined vent-surge tank to ambient; and a vent line fluidically connecting the upper part of the fuel tank to the combined vent-surge tank, wherein the vent line has its lowest point at the combined vent-surge tank.

Abstract: A fuel system includes a fuel tank, a vent tank fluidically connected to the fuel tank ullage, the vent tank having a duct open to the ambient atmosphere and the interior of the vent tank, and a catalyst disposed in the duct, wherein the catalyst is adapted to deplete one or more reactive components of gas flowing through the duct by catalytic reaction. Also, a method for depleting one or more reactive components of gas in the fuel system, includes depleting one or more reactive components of gas flowing through the duct using the catalyst.

Abstract: An aircraft fuel system including a fuel line for carrying liquid fuel, and a microwave energy transmitter for energizing water carried in the fuel line. Also, a method of suppressing ice formation in an aircraft fuel system, the fuel system including a fuel line carrying liquid fuel, and a microwave energy transmitter, the method comprising transmitting microwaves along the fuel line to energize water carried with the fuel in the fuel line.

Abstract: An aircraft fuel tank ventilation system, comprising a desiccative dehumidifying device including a desiccant medium disposed in flow communication between a vent open to the atmosphere and a fuel tank, and a microwave energy transmitter for energizing liquid water in the desiccant medium to facilitate regeneration of the medium. Also, a method of regenerating a desiccant medium of a dehumidifying device of an aircraft fuel tank ventilation system, the method comprising directing air through the desiccant medium, and transmitting microwave energy into the desiccant medium for energizing liquid water in the desiccant medium to facilitate regeneration of the medium.