aircraft fuel systems Flashcards
why are fuel tanks divided into compartments or have baffles installed in them
the compartments or baffles keep the fuel from surging back and forth as the aircraft changes its attitude in flight
how is a fuel leak indicated on a reciprocating engine powered aircraft
the dye in the gasoline stains the area around the leak
what is the function of the sump in a fuel tank
the sump, or lowest point, in a fuel tank is located below the fuel outlet. the sump collects water and contaminants and will have a drain to remove them
what are the three different types of fuel tanks
built up tanks, integral tanks, bladder tanks
what a problem can occur in a bladder tank with blocked vent
as internal tank pressure decreases, the pressure differential between the atmosphere and the tank can cause the tank restraint to fail and the tank can collapse and block the fuel outlet
how do you prepare an aluminum fuel tank for welding
remove all fuel and thoroughly wash the tank, inside and out, with hot water and detergent. the tank should be purged with live steam for at least 30 minutes to remove all residual fuel and vapors
after welding an aluminum fuel tank, to what pressure should the tank be tested
3.5 PSI
why is a fuel jettisoning or dump system required for some aircraft
a fuel dump system is installed on most large aircraft and allows the flight crew to jettison, or dump, fuel to lower the gross weight of the aircraft to its allowable landing weight
what color is grade 100 LL fuel
blue
how can you detect jet fuel in the sample taken from the tank sump drains
jet fuel is basically clear and it has an odor similar to kerosine
what must be done after fuel system strainer has been cleaned or replaced
the system must be tested for leaks by pressurizing the system with the boost pump, if one is used
what must be done if the sump drains sample shows traces of jet fuel
the fuel system must be drained and flushed out with the proper grade aviation gasoline
what is used as the sensor in the fuel tank for an electronic type fuel quantity indication system
tubular capacitors that extend across the fuel tank from top to bottom
what is the principle upon which the electronic type fuel quantity indicating system operates
tubular capacitors extending across the fuel tanks change their capacitance as the fuel level changes. the dielectric constant (k) of the fuel is approximately twice that of air
what is used as a sensor in the fuel tank for the older resistance type fuel quantity indicating system
a variable resistor with an arm that is moved by float riding on top of the fuel in the tank
