User manual

PFPX - Professional Flight Planner X
Aerosoft GmbH 2013
86 87
Designating an ETOPS alternate airport
Operators of airplanes with two or more engines are required to desi-
gnate the nearest available ETOPS alternate airport along the planned
route of flight and must remain within a 240 minute diversion time, if
possible.
Those areas not supported within 180 minute diversion authority tend
to be routes over remote areas of the world that are uniquely challen-
ging to the operation. These areas include:
• the South Polar region
• a small section in the South Pacific
• the southern South Atlantic Ocean between South America and
Africa
• the southern Indian Ocean
• the North Polar region under certain winter weather conditions.
The additional operational challenges of these routes are equally de-
manding of all airplanes, regardless of the number of engines, and in-
clude such issues as extremes in terrain and meteorology, as well as limi-
ted navigation and communications infrastructure. Support of a
necessary diversion and subse-quent recovery in such areas demands
added training, expertise and dedica-tion from all certificate holders.
Because of the natural variability of weather conditions with time, as
well as the need to determine the suitability of a particular en route al-
ternate be-fore departure, such requirements are higher than the wea-
ther minimums required to initiate an instrument approach. This is ne-
cessary prior to the time that the instrument approach would be
conducted, to provide for some deterioration in weather conditions af-
ter planning. This increases the prob-ability that the flight will land sa-
fely after a diversion to an alternate airport.
ETOPS Alternates are usually defined as pairs. The flying times to each
route-sequential pair of ETOPS alternate airports are greatest when at
the equal time point (ETP) between them. Equal time points are usually
calculated for each of: