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Automatic fl ight stabilization
With the AFS-system U-Turn provides an innovative feature. To fl y safely means to fl y actively - the
system employed on the U-Turn EMOTION 2 allows this to happen automatically to a certain level. The
secret of the AFS-system is based on a pre-tensioning principle. In the area of the brake attachment
points the undersurface is pre-tensioned. Whilst the sail is gliding through smooth air, there is enough
pressure inside and the pre-tensioning is neutralized: The eff ect of internal pressure is more powerful
than the pre-tensioning and the trailing edge stays aerodynamically perfect in the air like a conven-
tional glider. When entering turbulent air with the EMOTION 2 the system adjusts immediately, even the
slightest drop of internal pressure allows the system to react. The pre-tensioning at the trailing edge is
eff ectively like pulling the brakes.
Ernst Strobl recalls the fi ne-tuning: “Our computer-based calcualtions were impressivel confi rmed dur-
ing our tests”. The system is extremely responsive so that a top-quality manufacturing is key. U-Turn
Cofounder Thomas Vosseler adds: “We guarantee a strongly supervised manufacturing process”.
The AFS works like the Electronic Stability Programs known in the automotive industry, you could call
it an “ESP for the air”. It intervenes for the benefi t of safety when an inexperienced pilot, or a pilot in
trouble, enters turbulence and is unable to fl y actively. Experienced fl ight-instructors confi rm: “This is a
major step as far as safety is concerned. The main reason for accidents, the full collapse of the canopy,
is minimized dramactically”. Even without AFS the U-Turn EMOTION 2 would be a very safe glider says
Strobl. Due to the extremely pulled down wingtips and the resulting spread of the wingloading the U-
Turn EMOTION 2 has far more than average resistance to collapses. The EMOTION 2 gliders stably ahead
even after an accelerated asymmetric collapse, a situtation that may happen after leaving a thermal,
even with 50% of the wing area collapsed. This is unprecedented. The computer optimised wing layout
leads to very good thermal lift and maximizes the stall characteristics, both improving safety.
