POWER PLANT AND SYSTEM MONITORING

What kind of sensor is utilized to gauge the output of a low pressure booster pump?

What does the "Bourdon tube" measure?

An aircraft with a compensated capacitance fuel gauging system is refueled to a total of 76,000kg at 18 degrees C and an S.G. of 0.81. As the temperature rises to 26 degrees C and the S.G. changes to 0.80 while parked, how has the indicated fuel content changed?