Aircraft Fuel Systems — Page 333, Lesson 417

Right, let's pick up the fuel system panel. We're now looking at the external refuelling control panel, and I want to walk you through each control and indicator on it, because each one has a specific job. First, item 4 is the MODE SELECT switch, and it's guarded at OFF. That guard is there to stop you knocking it accidentally. It has three positions. OFF means the refuel system is de-energized and the refuel valves are closed. REFUEL means the refuel valves operate in automatic or manual mode, depending on the position of the refuel valve switches. And DEFUEL means the refuel valves and the transfer valve open. Next, item 5 is the TRF light, which stands for transfer. It comes on AMBER when the transfer valve is open. So if you see that amber light, you know fuel is being moved between tanks. Item 6 is the TEST switch, and it has two positions. HIGH will illuminate if the high level sensors and their associated circuits are serviceable. LTS, which stands for lights, illuminates the panel lights and shows all 8's on the fuel quantity indicator. So that's your self-test for the sensors and the display. Item 7 is ELEC POWER. This tells you the refuelling or defuelling can be powered by the GPU, the APU, or BATTERY 1. GPU is the ground power unit, APU is the auxiliary power unit. Item 8 is the PRESELECTED DISPLAY. This displays the preselected total fuel quantity in kilograms times 1000. So if it shows 12, that means 12,000 kilograms. Item 9 is the PRESELECTOR ROCKER SWITCH. Pressing either side of the switch increases or decreases the preselected quantity. So you set your target fuel load with this. Item 10 is the ACTUAL display. This shows the TOTAL fuel on board. So you have your preselected target and your actual current fuel, side by side. Item 11 is the AUTO REFUEL LIGHT. It comes on GREEN, and it shows END when automatic refuelling is completed. So when you hit your preselected quantity, this light tells you the job is done. Now, there's a very important operational rule that goes with this: refuelling with passengers on board, under EU-OPS 1.305. To reduce turnaround time and for security reasons, operators of fixed wing aircraft may allow passengers to embark, disembark, or remain on board during fuelling, but only if certain safety procedures are followed. Here are the key restrictions. It is not permissible to refuel a fixed wing aircraft with less than 20 seats while passengers remain on board. Passengers should disembark if wide-cut fuels are being used, for example Jet B. And passengers should disembark whenever AVGAS is involved. One qualified person must remain at a specified location during fuelling operations with passengers on board. That person must be capable of handling emergency procedures concerning fire protection and fire fighting, handling communications, and initiating and directing an evacuation. Crew, staff, and passengers must be warned that de/refuelling is about to take place. And finally, seat belt signs must be off. So the whole picture is: you set your target with the preselector, you watch the actual fuel build up, and the system stops automatically at your target. And if you're doing this with passengers on board, there's a strict set of rules about who can stay, what fuel can be used, and who must be ready to act in an emergency.