OptionalaltitudeAltitude in feet, if specified with A prefix.
OptionalflightFlight level (e.g. 350 for FL350), if specified with F prefix.
OptionalmachMach number (e.g. 0.82), if specified with M prefix.
Raw token from the route string.
OptionalspeedSpeed in km/h, if specified with K prefix.
OptionalspeedSpeed in knots, if specified with N prefix.
Discriminant for speed/altitude elements.
A speed and/or altitude group from the route string (e.g. "N0450F350").