Speed System With Spi - Advance acoustic EPSILON 9 Getting Started

Speed system with SPI

The Speed Performance Indicator ( SPI )
uses the EPSILON 9 polar curve and the
MacCready theory, and tells you the best
speed to fly. The SPI gives you an indica-
tion of the speed increase to choose tak-
ing into account headwind, sinking air and
the expected quality of the next thermal.
Take the time to set up your speed system.
Make sure that the speed lines run
§
freely through the harness pulleys.
Pull the speedlines through the harness
§
and connect them to the glider risers
using the Brummel hooks.
Adjust the length of the speed lines so
§
that pushing the first and second speed
bar steps reach SPI position 1 ( 30%)
and position 2 ( 80%) respectively.