Sinn 857 UTC, User Manual, Page: 15 / 35

15
TESTAF now provides the answers. For example, a pilot's watch must withstand
rapid temperature changes and changes in ambient pressure up to
0.044 bar – equivalent to an altitude of about 21,300 metres.
A pilot's watch is thus subjected to
several thousand pressure change
cycles in order to simulate the actual
stress conditions on a pilot's wrist.
Besides being water-resistant, the
watch must also be resistant to
common aviation fluids such as fuels,
hydraulic fluids and cleaning and
de-icing agents. It is also important
that the magnetic field of the pilot's
watch itself does not interfere with
the avionics such as the aircraft's
emergency compass. It may not
dazzle the pilot or produce
unnecessary reflections. The watch
must also be resistant to shocks and
vibrations and be perfectly readable
in the dark.
The certificate confirms that the
857 UTC TESTAF LH Cargo has
successfully passed the TESTAF test.