Originally Posted by Kitchen Bench
I can see she might have left YTWB off at the start but what's the purpose of DCT after the destination?
My two-bob's worth: there are three components of a flight, the departure and getting onto the route, flying the route, then getting off it and arriving. Checkboard's bus analogy is good.
In BEVLY 9's flight from YTWB to TCCA, the actual route is BIVAT Q303 YCCA, but you have to get yourself onto that, then off it at the other end.
If you're putting in a full flight plan, the departure airport (YTWB) and the destination (YCCA) are already in the notification from the fields you've completed. So what is needed is to link the Dep and Dest to the route. This is done in the Route field (Field 15 of the ICAO Flight Notification) with "DCT" at each end:
DCT BIVAT Q303 YCCA DCT
This tells the system you'll be flying from YTWB direct to BEVAT to join the route, then at the end, you'll be leaving the route at YCCA (final waypoint) to land at YCCA (airport).
The "YCCA" is the route may seem superfluous but it is acting as the destination "navaid". In the big scheme of things, possibly not critical for a VFR OCTA, but unless you know that the waypoint over your airport, you should use the enroute waypoint/navaid as the tracking point before you land.
The whole flight string therefore will look like this:
YTWB DCT BIVAT Q303 YCCA DCT YCCA
The issue is more important when departing YCCA (ie without a navaid). Depending on the nav system being used, you can get into bother if you depart and just hit LNAV, because you may not be joining the planned route but doing a Direct To. For example, take the YCCA to OPIPO segment. In my machine, if I depart with YCCA as the departure airfield and OPIPO as the "first" waypoint, when I hit LNAV the box takes me straight to OPIPO; it won't join the YCCA-OPIPO segment. If I put in YCCA as a waypoint before OPIPO (ie YCCA becomes the departure waypoint, additional to the departure airport), after I takeoff from YCCA, it will then manoeuvre to join the YCCA ("departure waypoint/navaid") - OPIPO segment, which is what I planned.
For the use of "DCT" when flight planning, check out the bottom of page 23 and 24 of AIP ENR 1.10 (note the non-sensical text in point b!
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