User manual

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Supplemental operations
Supplemental operations which is used for unscheduled flight opera-
tions, for example chartered flights, by an operator registered in the
United States under Supplemental operations, fuel rules are the same as
FAR 121 Domestic and US Flag operations. A Supplemental operation
must have a destination alternate airport nominated, regardless of wea-
ther, except when dispatching under island reserves.
Pilots flying for a single airline can expect all of their flights to be opera-
ted under a single fuel policy.
Route Planning
The route to be flown by an aircraft has two basic dimensions – a lateral
dimen-sion and a vertical dimension. The lateral route is usually speci-
fied as a set of geographic coordinates (latitude and longitude). The
vertical route is specified as a set of altitudes to be flown between geo-
graphic coordinates. Flying the lateral route is called lateral navigation
(LNAV), and flying the vertical route is called vertical navigation (VNAV).
Lateral navigation
The shortest distance between any two points on Earth (say, departure
and destination airports) is a line describing a great circle. Although a
commercial aircraft is required to fly along airways, the shortest distance
to be flown will be usually along those airways which are closest to the
great circle line.
Airways are designated routes in the air. Sometimes an airway is desi-
gnated as uni-directional, meaning it can only be flown in that direc-
tion. Intersec-tions, where two or more airways meet, are places where
a route may re-quire an aircraft to leave one airway to follow another.
Taking off from an airport, an aircraft will either follow a standard in-
strument departure (SID) - sometimes referred to as a departure proce-
dure (DP) - or be vectored by air traffic control to join an airway.