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Engine Data Management
Accumulate Total—Trip Total
You may either display total fuel
used
since the last time you informed
the EDM that the aircraft was refueled, or for an extended trip with
multiple fuel stops. This selection affects only the
USD
parameter. How
to select whether to accumulate or reset is described in “Pilot
Programming” beginning on page 36.
Resetting “USED”
Every time you inform the EDM that the aircraft is refueled, the amount
of fuel
used
is set to zero, unless the instrument is programmed to
accumulate. The display of fuel
used
pertains only to the fuel used since
the last time you informed the EDM that the aircraft was refueled.
To reset to zero the amount of fuel
used
at any point in time, manually
step to display
USD
and hold both buttons for five seconds until the
display shows .
0 USD
.
Fuel Management
Without a means of measuring fuel flow, you must rely on the aircraft
fuel gauges or total time of flight. Aircraft fuel gauges are notoriously
inaccurate (they are only required by the FAA to read accurately when
displaying
empty)
. And measuring time of flight is only an
approximation, and assumes a constant fuel flow rate for each phase of
flight.
The EDM Fuel Flow Option uses a small, turbine transducer that
measures the fuel flowing into the engine. Higher fuel flow causes the
transducer turbine to rotate faster which generates a faster pulse rate.
Because the transducer turbine generates thousands of pulses per gallon
of fuel, it can measure with high resolution the amount of fuel that flows
into the engine. Prior to engine start you inform the EDM Fuel Flow
Option of the known quantity of fuel aboard, and it will keep track of all
fuel delivered to the engine.
Parameter Scan—Systems with Fuel Flow Option
The EDM steps through the engine parameters in a specific sequence.
Listed below is the sequence, parameter description and example of the
digital display.
