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

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PRISM FLIGHT MANUAL
36
If operating in excessively HOT conditions (90F/ 32C and above), it is recommended that
the pilot:
Keep the aircraft in a shaded area when not in flight. Do not allow the drone to be
exposed to direct sunlight when not in use
Keep the flight batteries in a shaded area when not in flight. Ensure that the
batteries are not exposed to direct sunlight while charging.
If operating in excessively COLD conditions (40F/ 4C and below), it is recommended that
the pilot:
Plug in the aircraft and allow the autopilot to warm up to proper operating
temperature. The Cube flight controller offers a heated IMU, which when powered
up will attempt to bring the IMU up to proper operating temperature. It is
recommended that pilots allow the autopilot to warm up for at least 5 minutes
before flying if the aircraft has been sitting in cold temperatures.
Keep the batteries in a warm environment when not in flight. It may be useful to
keep these in a vehicle when not in use or while charging.
Increased air temperatures affect the density of the air in which the RPA operates. Similar
to an increase in altitude above sea level, higher temperatures create a lower air density.
Operating in this “thinner” air reduces the power available and requires faster propeller
RPMs for the same amount of thrust at a lower temperature. This has a negative effect on
the endurance of the RPA, and when compounded with the loss of motor efficiency can
result in noticeably less flight time.
Flight operations are to be carried after taking into account the current density altitude (a
function of air temperature and elevation) of the flight operations area.
Lithium Polymer chemistry is affected by the ambient temperature. This effect is most
noted in cold conditions (Below 10° C) when the rate of chemical reaction is slowed and
the cells’ ability to supply power is diminished. This means less instantaneous power
delivered to the RPA (Lower discharge rating) as well as less overall capacity available
(Less endurance). Storing the battery packs in a warm place until immediately
before use will minimize the loss of performance.
5.3.1 AIR DENSITY (DENSITY ALTITUDE)
5.3.2 BATTERIES