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WEATHERCONDITIONS
Exceptwhen operating an aircraft under theVFR by daywithin 50nmof the
point of departure, the pilot in commandmust provide for a suitable alternate
aerodromewhen arrival at the destinationwill be during the currency of, or up
to 30minutes prior to the forecast commencement of, the followingweather
conditions:
• cloud–more thanSCT below the alternateminimum; or
• visibility–less than the alternateminimum; or
• visibility–greater than the alternateminimum, but the forecast is endorsed
with a percentageprobability of fog,mist, dust or any other phenomenon
restricting visibility below the alternateminima; or
• wind–a crosswind or downwind componentmore than themaximum for
the aircraft.
Note: Windgustsmust be considered (AIPENR 1.1).
Note: Indetermining requirements for alternate aerodromes, forecast
amountsof cloudbelow the alternateminima are cumulative. For
determining requirements, the cumulative cloud amount is interpreted
as follows:
— FEW plus FEW is equivalent toSCT;
— FEW plus SCT is equivalent toBKN;
—SCT plus SCT is equivalent toBKN or OVC (AIPENR1.1).
ALTERNATEMINIMA
For flight by aeroplanes under theVFR (day or night) and helicopters operating
under theVFR at night, the alternateminima are a ceiling of 1500 ft and a
visibility of 8 km (AIPENR 1.1).
When operating a helicopter under theVFR, and theuse of the helicopter
VMC is permissible at the destination, thepilot in commandmust provide
for a suitable alternate aerodromewhen either of the following conditions is
forecast at the destination:
• cloud -more thanSCTbelow a ceiling of 1000 ft; or
• visibility - less than 3000m (AIPENR 1.1).
alternatedue toweather
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