Hi,
In Fukuoka FIR, people are supposed to not put “DCT” between two points if it meets one of the following conditions.
A) Two points are part of a “designated ATS route” on AIP. (≒the route is a published direct route)
B) The flight is within Fukuoka FIR
C) Both points are indicated by latitude and longitude
D) Both points are indicated by the bearing and distance from navigation aid
This should be 99% of the time, especially when we, the VATJPN Air Traffic Management Team, have finished adding user-submitted routes.
In the case of the US, DCTs are shown in the ICAO format flight plan when a user generates an OFP, but when one uses the “Prefile on VATSIM” function, they are removed, if I remember correctly. Is it possible to have the same feature for Fukuoka FIR (RJJJ) to?
For official reference, I quoted relevant parts in the ENR 1.10 (FLIGHT PLANNING) section in the AIP.
(A) When the point that should be indicated does not exist along the route, if the flight along designated ATS routes, insert the coded designated ATS routes, if not the flight along designated ATS routes, insert the letters "DCT".
d) The letters "DCT" may be omitted if the flight is along designated ATS routes and the case as follows.
i) In take case of the flight within Fukuoka FIR
ii) When the points that put "DCT" between are indicated by latitude and longitude in degrees
iii) When the points that put "DCT" between are indicated by the bearing and distance from navigation aid