What type of fuel quantity indicating system measures fuel in pounds?

The capacitance-type fuel quantity indicating system is designed to measure the amount of fuel in terms of weight, specifically in pounds or kilograms. This system operates based on the principle that the dielectric constant of fuel is different from that of air. As fuel fills the tank, the capacitance changes, and this change is correlated to the fuel's weight.

In modern aircraft, the use of capacitance-type systems provides accurate and reliable readings of fuel quantities, which are important for flight planning, fuel management, and safety. The design allows for continuous measurement, meaning the pilot can monitor the fuel levels in real-time and make informed decisions about fuel usage and landing requirements.

Other systems, such as mechanical or electronic, may not focus directly on weight as a measurement unit, and the Bourdon tube is primarily a pressure measurement device. Therefore, while those systems may provide valuable data, they do not specifically measure fuel quantity in pounds, making capacitance-type the correct choice for this question.