Fuel Policy and Fuel Monitoring — Page 38, Lesson 50

Let’s start with the scenario that leads us to the Decision Point Procedure. Imagine you’re planning a flight from Oxford to Faro in southern Portugal. You’ve got alternates near Faro — Seville or Jerez, for example. The total of your final reserve fuel plus the alternate fuel comes to 3 000 kg. Your trip fuel is exactly 10 000 kg. Because there’s a suitable en‑route alternate at Lisbon, your contingency fuel is only 3 % of the trip fuel, which works out to 300 kg. So the minimum fuel you need at take‑off is 13 300 kg. But here’s the problem: the maximum capacity of your fuel tanks only lets you get 13 150 kg on board at take‑off. That’s 150 kg short of the minimum requirement. Does that mean you can’t do the flight? Not necessarily — not if there’s a suitable en‑route alternate. We define the top of descent for going into Lisbon, our en‑route alternate, as the Decision Point. We have plenty of fuel to proceed to Lisbon, so that leg is legal. At this Decision Point, we carry out a fuel check. Unless unforeseen circumstances have arisen, we will probably not have used the contingency fuel, so we’ll still have 150 kg above the expected consumption line for Faro. Now here’s the key rule: the requirement for contingency fuel is 3 % above the trip fuel required for the remainder of the flight — not the trip fuel at the start. At this stage of the trip, the required contingency fuel is only 55 kg. If the fuel remaining includes that 55 kg contingency fuel, plus the remainder of the trip fuel for Faro, along with the usual alternate fuel and final reserve fuel, we continue to Faro. If the fuel remaining comes to less than that figure, we divert to our alternate, Lisbon. So the Decision Point Procedure is a special case that lets you get airborne with less than the full contingency fuel for the whole trip, as long as you have a suitable en‑route alternate and you check your fuel at that decision point. It’s a legal way to handle a situation where your tank capacity is just a little short of the normal minimum.