Advance EPSILON 6 Série Manuel D'utilisation page 45

Thanks to its high stability the EPSILON 6 can be flown in accelerated
condition in light turbulence without problem. The choice of acceler-
ated speed for best glide does play an important role for a relatively
high performance intermediate glider.
Each of the EPSILON 6 SPI positions has an icon with a value for
headwind, expected climb and sink rate. These indicated positions
are effective for only one of their three values, taken in isolation -
considered by itself. This means that either the headwind, or the
expected rate of climb, or the sink rate applies to that position. The
SPI principle is based on the simple (using headwind and sink) and
the extended (including expected climb rate) McReady Speed-To-Fly
theory.
Headwind
Expected climb
Sink rate
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