AIRCRAFT OPERATING INSTRUCTIONS – VIRUS 912 S-LSA GLIDER
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CAUTION!
It is not recommended to fly the aircraft at speeds exceeding 80 kts (150 km/h) using
flap setting other than negative.
CAUTION!
Check fuel upon establishment of cruise attitude. Because of the fuel system design,
the fuel tends to gradually cross-flow from the right tank to the left. To prevent this, shut the
right fuel valve and open it again when the fuel level inside left tank has lowered.
CAUTION!
If the fuel quantity in a fuel tank is low, it is possible that the engine starts to suck air
into the fuel system. To prevent this and consequent engine failure, always close the fuel valve of
the tank where the fuel quantity is very low.
Cruising in rough conditions.
Should you experience turbulence, reduce airspeed to V
A
, 76 kts,
and continue flying with flaps set to neutral position.
CAUTION!
In rough air, reduce engine power if necessary to keep airspeed below V
A
.
Descent and final approach
Descend at speeds at or below V
A
and flaps in negative stage. To expedite descents, use
airbrakes (if applicable) and keep airspeed below VAE. For approach, reduce speed to 70 kts (130
km/h) and set flaps to 1st position only after turning to base leg. Adjust engine power to
maintain proper airspeed. Set trim to neutralize stick force if necessary. During the descent
monitor temperatures and keep within operational limits.
CAUTION!
During the descent, engine power MUST be reduced. Should you be forced to
descend at idle power, make sure you keep adding throttle for short periods of time, this will
help to keep spark plugs clean.
CAUTION!
With flaps in 2nd position, no more than half of the available aileron deflection is
permitted.
On final, set flaps to 2nd position. Align with the runway and reduce power to idle. Extend
airbrakes (as required) and maintain an airspeed of 55 kts (102 km/h). Instead of throttle use
airbrakes to control your descent glide path. Otherwise, control your attitude and crab or slip as
necessary.
CAUTION!
Crosswind landings require higher final approach speeds to ensure aircraft’s safe
maneuverability. Increase the approach speed by 1 kts for every 1 kts of crosswind component
e.g. in case of 5 kts crosswind component, increase the approach speed by 5 kts.
Roundout and touchdown
CAUTION!
See chapter “Performance” for landing performance.
Roundout and touchdown (flare) occurs at following airspeeds:
CAUTION!
Land the aircraft in such a manner that the two main wheels touch the ground first,
allow the nose-wheel touchdown only after speed has been reduced below 25 kts. When
lowering the nose wheel to the runway, rudder MUST NOT be deflected in any direction (rudder
pedals centered).
