Fuel Flow Instruments-How It Is Performing During the Flight

Since the beginning of the Wright Brothers’ invention, providing pilots with useful flight information has been deemed of utmost importance. Even the Wright Brothers were concerned about the flight engine’s performance and flight progress. Since then, various flight instruments have come into existence to inform the crew about several parameters.

Information, such as; aircraft condition, engine performance, flight progress, the attitude in the sky, weather conditions, cabin environment, pressure, navigation, and communication; has always been considered of vital importance. Various companies are striving to produce instruments to improve pilots’ performance and safety during the flight.

Throughout aviation history, providing accurate and easily understood information to the crew has remained a challenge because the range of desired information is growing with time, so is the design and complexity of an aircraft.

Among such vital information, tools are fuel flow instruments which provide various types of information, related to fuel, to the pilot. Some of these instruments are briefly described below:

Fuel Pressure Gauge:

Fuel is pumped out by several tanks to the engine to maintain the desired output pressure. If fuel level falls below a specific limit in any one of the tanks the pilot must take immediate actions.

Fuel flow instruments allow pilots to pump, manage, and provide fuel to the propulsion system and Auxiliary Power Unit of an aircraft. Fuel instruments differ with the complexity of an aircraft as different kinds of airplanes require different levels of fuel performances.

Fuel flow:

This type of sensor is usually located in the lower part of the aircraft’s body, behind the fuel filter and instrument measuring the amount of fuel being delivered to the engine.

Those engines which have fuel injected sometimes have some amount of fuel that returns to the tank. Therefore, to get a more accurate reading the amount of fuel that is returning to the tank should also be measured with the help of a flow sensor.

The Electronic Fuel Flowmeter:

Liquid flow can be measured in various ways ranging from mechanical to ultrasonic/Doppler.

There are several products available in the aviation market, and most of them make use of a miniature turbine which mainly consists of a magnet and a fixed coil that is responsible for generating a pulse. This pulse is amplified and is delivered to another Airplane Gauges instrument, mounted on a panel, which converts the pulse reading into a more direct measurement of fuel flow in liters, or gallons, per hour.


Without a means of fuel flow indication, a crew must totally depend on the aircraft’s fuel EGT Gauge, which are unbelievably inaccurate at times, or total air time, which also is only an approximate indication.

Therefore, you require fuel flow instruments that give you a more accurate reading about the amount of fuel flowing to the engines. For instance, the FS-450 Fuel Scan, provided by JP Instruments.