twin engine fuel rate & economy - node-red flow

[gregsyoung]

for twin engines, each supplies respective instantaneous fuel rate ...
this flow computes combined (instant) fuel rate and economy (litres/naut mile) ... also instantaneous
the flow checks for existence of a fuel rate - otherwise it would error out with "undefined" output
.. it probably should have a further check on each engine ... as prior to start of second engine.. it likely produces undefined output also.
fuel rate.txt

[gregsyoung]

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[gregsyoung]