BFI57 / P/N BFI57-(xxx)-(xxx)
Operation and Installation
Document-No.: 08.510.010.71e/ Revision: 3.10
15
This is depicted in the following diagram:
As the vertical pressure gradient (the decrease of the static
pressure with increasing altitude) varies with the weather,
the automatic QNH determination is most accurate close
to the ground in vicinity of the destination airport. If the
automatic has been activated in greater altitudes, shortly
before reaching the traffic circuit altitude another activation
should be performed, to correct possible inaccuracies.
The device can be set to perform the automatic QNH
determination automatically once each time after being
turned on (see 2.5.2.1).
With this, for short flights no interaction is required at all!
Start of the automatic QNH determination
by long pressing
GPS position OK
No GPS reception
device tries to
determine QNH
from GPS
position
shortly
indi-
cated
new QNH,
with mode A
old QNH,
with mode M
Summary of Contents for BFI57
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