FMS Guide

Aerosoft – Digital Aviation
CRJ-700 CRJ-900
FMS Guide
Revision Info
VOL
6
1-1-42
23-Apr-2017
ROUTE STRINGS AND ITS APPEARANCE IN THE FMS
The following descriptions are based on the assumption that at least the departure runway and the respective
SID was selected on the DEP/ARR page. Accordingly the last waypoint of the SID appears on the FPLN page.
FMS_55.jpg
Roughly 30-40 years ago aircraft navigation was mainly (especially flying cross-country) done navigating from
VOR to VOR or NDB. Those navigation aids were connected by airways, somewhat comparable to highways
connecting cities. The SIDs and STARS are the ramps to enter and leave the highway.
To cross the Atlantic ocean or other huge bodies of water inertial navigation systems were used. As VORs are
also not available when passing oceans, waypoints were defined, which designate an identifier (the unique
waypoint name) to a pair of coordinates (latitude and longitude). Accordingly the airways are connecting
waypoints in this case.
As keeping VORs and NDBs running costs money and they can easily be replaced by a waypoint (it just needs to
be defined and located at the very same coordinates) the trend is to use less VORs and NDBs and more
waypoints.
Similar to describing a route to drive with your car, route strings describe the route an aircraft is supposed to
follow. For example:
EDDF MARUN Y153 WRB N850 NIE Z88 VERED EDDW
So let’s take a closer look:
Waypoint 1
Airway
Waypoint 2
Comment
EDDF
MARU3T
MARUN
This example flight leaves Frankfurt/Main. The first
waypoint on our route is MARUN, so we need a suitable SID
ending at MARUN (for example MARU3T departing runway
18)
MARUN
Y153
WRB
The first leg of our flight starts at MARUN and follows
airway Y153 to Warburg WRB VOR
WRB
N850
NIE
At Warburg WRB VOR we switch to airway N850, following
to Nienburg NIE VOR
NIE
Z88
VERED
At Nienburg NIE VOR we switch to airway Z88 and follow it
to waypoint VERED
VERED
VERE3P
EDDW
At VERED we follow the VERED3P STAR into Bremen
(EDDW)