TBM
PILOT’S OPERATING HANDBOOK
700
SECTION 7
DESCRIPTION
Page 7.7.4
Edition 1 -- November 30, 2010
Rev. 0
TANK AUTOMATIC SELECTOR
(Figures 7.7.3A and 7.7.4A)
Tank automatic selection allows, without pilot’s intervention, feeding the
engine from one tank to the other in predetermined sequences. These
sequences depend on airplane configuration (ground, in--flight, fuel low level
CAS messages appearance).
Tank automatic selection system comprises an electronic box (sequencer),
an actuator attached on fuel unit, ”FUEL SEL” two--position selector
(”AUTO”, ”MAN”) and ”SHIFT” knob located on ”FUEL” panel.
To operate the automatic selector, set ”FUEL SEL” switch to ”AUTO” position
and manual selector to R. or L.
Selector operation
When the system is operated, ”AUTO SEL” CAS message disappears ; the
sequencer chooses a tank (”R” or ”L”) and through the actuator, positions the
fuel unit selector on the selected tank. The sequencer controls the time
during which the selected tank will operate. This time varies, depending on
airplane conditions.
Airplane on ground : tank is changed every minute and 15 seconds.
Airplane in flight : tank is changed every ten minutes, as long as a fuel low
level CAS message does not appear. When the first low level CAS message
lights on, the sequencer immediately selects the other tank. The selected
tank will operate until the second low level CAS message lights on. When
both low level CAS messages are visible, the sequencer changes tanks
every minute and 15 seconds.
NOTE :
The manual selector is driven by the fuel unit and is positioned on ”R ” or ”L”
mark corresponding to the tank selected by the sequencer. Therefore, the
pilot continuously knows the tank which is operating.
