Fuel and Fire Detection Systems

Question 1

What is the maximum fuel capacity when fuelled only via pressure-fuelling?

Answer 1

1100lbs (530lbs in each wing tank and 40lbs in the collector tank).

Question 2

What is the maximum fuel capacity when fuelled via pressure-fuelling, then over-wing fuelling?

Answer 2

1200lbs (580lbs in each wing tank and 40lbs in the collector tank).

Question 3

What is the purpose of the level control shutoff valves?

Answer 3

To stop pressure fuelling before the tank is completely full - this stops the tank blowing up under pressure.

Question 4

At what pressures to the Pressure and Vacuum Relief Valves activate?

Answer 4

-1.7PSI and +1.7PSI

Question 5

Below what fuel pressure will the Boost Pump automatically activate?

Answer 5

10PSI

Question 6

What kind of sensors are used to measure the precise fuel levels in each wing fuel tank?

Answer 6

Three capacitor sensors in each wing tank.

Question 7

What kind of sensors are used to detect low fuel in the wing tanks and collector tank?

Answer 7

Optical Sensors.

Question 8

Describe the operation of the Fire Detection System.

Answer 8

Two sensor tubes surround the engine. They contain a hydrogen charged core, surrounded by helium gas. High temperatures cause hydrogen to be released from the core material. This causes the pressure in the tubes to rise, triggering diaphragms, which activate the CAS Fire alert. Lower temperatures will cause the hydrogen to be re-absorbed, cancelling the alert.