Horizon Hobby EFL17750, Instruction Manual

Page: 12 / 68

EN
Viper 90mm EDF
12
Flying Tips and Repairs
Consult local laws and ordinances before choosing a flying location.
Getting Started
Before you fly, range check the radio system. Refer to your specific transmitter
instruction manual for range test information. When you first connect the battery to
the airplane AS3X will not be active. After advancing the throttle past 25% the first
time, the AS3X system will be active and it is normal to see the control surfaces
react to aircraft movement. For your first flights set your transmitter timer or a
stopwatch to 3.5 minutes. Adjust your timer for longer or shorter flights once you
have flown the model.
Takeoff
Face the aircraft into the wind for takeoff. Set your transmitter to low rates, set
the flaps to the take-off position, and gradually increase to full throttle. Steer on
the ground with the rudder as necessary to keep the aircraft rolling straight. Be
aware the nose wheel will become more sensitive as speed increases. Leave the
elevator at neutral and allow the aircraft to accelerate up to speed on the ground,
then pull up gently on the elevator to rotate for takeoff. When airborne, climb to a
comfortable altitude, retract the landing gear, and raise the flaps to normal position.
Flying
For your first flights climb to a moderate altitude and get comfortable with
the aircraft while the battery is fresh. Get a feel for the aircraft’s low speed
performance at a safe altitude (approximately 100 feet or more) before being
required to make your first landing attempt. Land the aircraft when the timer
expires. If at any time the motor power reduces, land the aircraft immediately
to recharge the flight battery. See the Low Voltage Cutoff (LVC) section for more
details on maximizing battery health and run time.
Landing
Plan to land the aircraft into the wind when possible. Fly downwind, set the flaps to
the take-off flap position, and turn into the wind to begin the approach. Extend the
landing gear, lower the throttle. During the approach and descent, keep the wings
level and the aircraft pointed into the wind. The attitude (angle of the aircraft
relative to the horizon) should remain consistent and slightly nose-high during the
decent. With the angle of attack maintained during the descent, the speed and
descent rate is mostly controlled with small throttle changes. Once confirmed, you
can make the runway set the flaps to the landing position, and stay in the throttle
to maintain speed and control during descent until the aircraft is ready to flare. As
the airplane descends into ground effect, fully lower the throttle, pull the nose up
more to bleed off airspeed (flare), and the aircraft will settle on its wheels.
If landing on grass, it is best to hold full up elevator after touchdown and when
taxiing to prevent the nose from digging in. Once on the ground, avoid sharp turns
until the plane has slowed enough to prevent scraping the wingtips.
NOTICE: If a crash is imminent, reduce the throttle and trim fully. Failure to do so
could result in extra damage to the airframe, as well as damage to the ESC and
motor.
NOTICE:
After any impact, always ensure the receiver is secure in the fuselage.
If you replace the receiver, install the new receiver in the same orientation as the
original receiver or damage may result.
NOTICE: Crash damage is not covered under warranty.
NOTICE:
When you are finished flying, never leave the aircraft in direct sunlight
or in a hot, enclosed area such as a car. Doing so can damage the aircraft.
Low Voltage Cutoff (LVC)
When a Li-Po battery is discharged below 3V per cell, it will not hold a charge. The
ESC protects the flight battery from over-discharge using Low Voltage Cutoff (LVC).
Before the battery charge decreases too much, LVC removes power supplied to the
motor. Power to the motor reduces, showing that some battery power is reserved
for flight control and safe landing.
Disconnect and remove the Li-Po battery from the aircraft after use to prevent
trickle discharge. Charge your Li-Po battery to about half capacity before storage.
During storage, make sure the battery charge does not fall below 3V per cell. LVC
does not prevent the battery from over-discharge during storage.
NOTICE: Repeated flying to LVC will damage the battery.
TIP: Monitor your aircraft battery’s voltage before and after flying by using a Li-
Po Cell Voltage Checker (SPMXBC100, sold separately).
Oscillation
For most flight maneuvers the aircraft should fly smoothly and normally, but it is
possible in some flight conditions you may see oscillation (the aircraft rocks back
and forth on one axis). If oscillation occurs, refer to the Troubleshooting Guide for
more information.
Repairs
Thanks to the EPO foam material in this aircraft, repairs to the foam can be made
using virtually any adhesive (hot glue, regular CA, epoxy, etc). When parts are not
repairable, see the Replacement Parts List for ordering by item number. For a listing
of all replacement and optional parts, refer to the list at the end of this manual.
NOTICE:
Use of CA accelerant on your aircraft can damage paint. DO NOT handle
the aircraft until accelerant fully dries.
SAFE Select Flying Tips
When flying in SAFE Select mode the aircraft will return to level flight any time the
aileron and elevator controls are at neutral. Applying aileron or elevator control will
cause the airplane to bank, climb or dive, and the amount the stick is moved will
determine the attitude the airplane flies. Holding full control will push the aircraft to
the pre-determined pitch and roll limits, but it will not go past those angles.
When flying with SAFE Select it is normal to hold the control stick deflected with
moderate aileron input when flying through a turn. To fly smoothly with SAFE Select
avoid making frequent control changes and don’t attempt to correct for minor
deviations. With SAFE Select, holding deliberate control inputs will command the
aircraft to fly at a specific angle and the model will make all corrections to maintain
that flight attitude.
Return the elevator and aileron controls to neutral before switching from SAFE
Select mode to AS3X mode. If you do not neutralize controls when switching into
AS3X mode, the control inputs used for SAFE Select mode will be excessive for
AS3X mode and the aircraft will react immediately.
Differences between SAFE Select and AS3X modes
This section is generally accurate but does not take into account flight speed, bat-
tery charge status, and many other limiting factors.
• In SAFE Select mode the aircraft will self level when the control stick is neutral-
ized.
In AS3X mode the aircraft will continue to fly at its present attitude when the
control stick is neutralized.
• In SAFE Select mode holding a small amount of control will result in the model
banking or pitching to a moderate angle and remaining at that angle as long as
the control stick doesn’t move.
In AS3X mode holding a small amount of control will result in the model continu-
ing to pitch or roll at a slow rate as long as the control stick doesn’t move.
• In SAFE Select mode holding full control will result in the airplane banking or
pitching to the predetermined limits and the aircraft will keep flying at that at-
titude as long as the control stick is fully deflected.
In AS3X mode holding full control will result in the aircraft pitching or rolling at
a high rate, and it will continue to rapidly change attitude as long as the control
stick is fully deflected.