the proper temperature in the chilled fuel reservoir 7 via cooling ports 10 pre flight during aircraft fuel loading intake valve 15 is maintained in the open position at all other times it is closed during flight chilled fuel reservoir outlet valve 17 is open unless a threat of crash or accident exists in which case it may be closed the position of each of valves 15 and 17 is monitored and controlled by fuel monitoring and control system 22 chilled but not frozen fuel leaves the reservoir 7 and passes through valve 17 into fuel supply line 25 it then is pumped by fuel pump 45 after which it passes through another segment of fuel supply line 25 pressure and flow may be monitored within each of supply lines 25 and this information is supplied to fuel monitor and control system 22 fuel then passes through warming chamber intake valve 33 and enters the warming chamber it leaves this chamber through warming chamber outlet valve 36 if necessary this chamber may be sealed by closing valves 33 and 36 the position of valves 33 and 36 is monitored and controlled by fuel monitoring and control system 22 after passing through fuel line 42 fuel pump 44 fuel line 49 fuel filter 50 and intake valve 60 the warmed fuel enters warmed fuel reservoir 61 all other components and operations of fig3 are the same as those shown in fig1 whereas fig3 shows two fuel pumps and one filter clearly a greater or lower number of pumps and or a greater number of filters may be provided fig4 shows an embodiment of the invention in which a first composition is added to the fuel in order to decrease its combustibility and thereafter a second.