WATTS INNOVATIONS PRISM R.P.A.S., Flight Manual

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PRISM FLIGHT MANUAL
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(ii) Ground Control Station Link Loss (GCS FAILSAFE)
This mode is relevant during missions in AUTO mode, where the Pilot is not controlling the
RPA manually via the radio control. It may be the case that the RPA is operating beyond the
range of the Radio Control link.
In the event of a sustained loss of the Ground Control Station link between the RPS and
the aircraft, the RPA can be set up to perform two actions: The aircraft can be set to RTL
regardless of flight mode (the default setting); or it can continue the mission in AUTO
mode even while the C2 link is lost.
The failsafe settings are configured in the WattsQGC application. By default, the GCS
Failsafe is not enabled, as the RPA has dual communication with the GCS (either by Radio
or by Datalink). Only the loss of RC Control will initiate a RTL. For example, if the pilot exits
WattsQGC during flight, the aircraft will not initiate a RTL. However, if the pilot turns off
the EchoSky Mobile handset while in flight, this will initiate a RTL, as the RC radio itself
has been turned off.
(iii) Battery Failsafe
If the battery voltage drops below the Low Voltage Threshold, the RPA will enter low
battery Failsafe mode. This is indicated by a Yellow Flashing Status LED and on the GCS
monitor. The RPA will enter
RTL mode
and begin to return back home. The pilot is to
terminate the flight and land as soon as possible, as the battery failsafe does not factor in
travel time to the home location.
The second level of battery failsafe is invoked when the voltage drops below the CRITICAL
VOLTAGE threshold. In this case, the RPA will enter
LAND mode
and begin an automated
descent in place. This mode is a last resort to prevent total battery depletion while in the
air. The LED will turn Flash red and Critical Battery Voltage will be displayed on the GCS.
Low battery Failsafe procedures are described in more detail in
Chapter 8: Emergency
Procedures.
CAUTION:
It may be the case that while executing an AUTO mission, the RPA is beyond the range of both
video and control communication links. The Pilot will not receive telemetry information or be able
to control the RPA. This situation should be avoided by comprehensive mission planning, taking
into account control link range and LOS conditions.
WARNING:
Low Battery is the leading cause of RPAS incidents. The Pilot should never let the battery
voltage drop to either of the battery failsafe thresholds during normal operations. Flights
should be planned to land before Battery Failsafe is invoked.