Diamond DA 42 NG, Maintenance Manual

Page: 951 / 2339

AIRCRAFT
DA 42 NG AMM Fuel
Doc # 7.02.15
Rev. 4
28-10-00
Page 3
15 Mar 2018
2. Main Fuel Tank Description
A. Main Fuel Tank
Figure 1 shows the fuel tank installation. The airplane has two fuel tank assemblies. One in the left
wing and one in the right wing. Three chambers connected by flexible couplings make the fuel tank
assembly. The three chambers are outboard of the engine nacelles and are located between the
main spars of each wing.
Each chamber is a welded aluminum structure. Each chamber has an oval cross section and flat
end plates. Baffles in the chambers prevent the fuel from moving quickly from one end of the tank
to the other. The chambers have bosses welded into the end plates to make connections for the
flexible hoses and other components that attach to the end plates of the chambers.
A tank outlet is located at the inboard end plate of the inner chamber. A finger filter at the tank
outlet prevents debris from entering the engine fuel systems. A drain valve is located at the lower
surface of the inner chamber. You can use this drain valve to check for fuel contamination and for
draining the fuel tanks.
A fuel temperature sensor and a low fuel sensor are also mounted on the inboard end plate of the
inner fuel tank chamber. The fuel return/transfer line also connects to the inboard end plate. The
outer end plate of the inner chamber has mountings for the flexible connecting hose and a fuel high
level switch.
The end plates of the middle chamber have fittings attached for the flexible connecting hoses that
join the middle chamber to the inner and outer chambers.
The inboard end plate of the outer fuel chamber has fittings attached for the flexible connecting
hose and a fuel high level switch. The inboard end plate also has fittings attached for the fuel tank
vents. The top surface of the outboard fuel tank has an attachment for the fuel filler assembly.
Fuel level sensors are installed in both the inner and outer chambers. The sensors go from the
lower inboard corner to the upper outboard corner of each chamber. The signals from the sensors
are displayed on the MFD of the integrated cockpit system. Refer to Section 28-40 for more data
about the fuel indicating system.
Ribs and the two main spars of the wings hold the fuel tank chambers in position. Rubber strips go
between the tank chambers and the ribs. The filler cap assembly is attached to the upper surface
of the wing with screws which holds the tank assembly in position.