Page 705 - PPL-engelsk 2025
P. 705
Aircraft general knowledge
8.5.2.1 Gravity fed system
High-mounted gasoline tanks are supplying the engine without the need for a
fuel pump. For safety an extra pump may be attached to the system.
8.5.2.2 Integral tank
The integral tank is a construction where you
block off part of the wing and use this as a fuel
tank.
The advantage may be that the tank is spacious
and light in weight, since there is nothing more
than end plates and gaskets for the construction.
The disadvantages are that such a tank can leak, and then it is difficult to repair.
When removing fuel from the bottom outlet of the tank, it is important that
there is an air supply so that no negative pressure/vacuum is formed above the
gasoline. There is usually a valve in the fuel caps that ensure air supply.
8.5.2.3 Drains and condensation
Condensation forms in fuel tanks. Drains are therefore placed at the lowest
points in the tank (water is heavier than fuel). The collected fuel is returned to
the tank, unless it is contaminated. Make sure that the fuel is of the correct color.
There are drains in both tanks and a filter drain, which we use before the first
flight of the day to ensure that there is no water or impurities in the fuel.
Water will collect at the bottom of the drain glass – if there is any.
It is important to drain this water away when inspecting the aircraft before flight.
Remember to also drain the fuel filter.
Flyveteori PPL(A)(UL)/LAPL Henning Andersen, Midtjysk Flyveskole© 2025 705
