RAD/DIS Offset
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Sorry for a bit of a long post.
One thing, something giving me a bit of trouble in the CDU is the usage of RAD/DIS offsets.
In their basic function, they are working fine, but trouble starts appearing if you try to also use the "base waypoint" in any other way. It seems that adding the offset moves the base waypoint for any other operation as well. So no option of defining a waypont at a distance from a fix and then flying to the base fix, as the ident will now give the offset coordinate. Not sure if this is also a real life limitation.First time I played around with the functionality was flying into EKRK via TNO. There is a level restriction of max FL70 20 NM prior to TNO. So I offset TNO by 20 NM on the radial I was flying inbound along, and I could now enter 7000 on the V NAV page and get the needed VS - simply lovely
Trying to insert TNO as the next waypoint after the offset version then gave trouble. Fair enough it's a VOR anyway so I could navigate via that, or insert the co-located RNAV waypoint RK361 in this case.
When I then tried to insert the ILS21 via TNO transition approach, that also started at the offset point 20 NM off from TNO.
In the end I gave up on finding a way of inserting it all and simply flew the procedure using VOR1 with no overlay from the FMS.
From my playing around, it seemed that an alternative option was to create a user waypoint, but as those are only definably via coordinates and not RAD/DIS it is quite some extra work. Didn't try it at the time, but I guess I could also have defined the custom points via the joystick.
Making 2 different RAD/DIS points with different offsets from the same "base waypoint" also seems to be impossible (was trying to see if I could add a couple of "checkpoints" on a DME arc).So in the end to summarise everything - I wonder if RAD/DIS is working as intended. With the way it renames the offset waypoint I would guess that the base waypoint would still be usable in the real world.
(Also have had some weird behaviour when deleting an offset waypoint and the offset name sticking with it if you try to insert the base waypoint again, but don't have the specifics yet to give a full description.) -
I ran into the same problem being unable to create a RAD/DIS offset and then the original waypoint when I tried to create an approach fix to aid in visual approach. I created a RAD/DIS of the airstrip, but was then unable to add the airstrip itself after that.
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Also wondered how it is possible to use both (original WP and Offset)
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Sorry for a bit of a long post.
One thing, something giving me a bit of trouble in the CDU is the usage of RAD/DIS offsets.
In their basic function, they are working fine, but trouble starts appearing if you try to also use the "base waypoint" in any other way. It seems that adding the offset moves the base waypoint for any other operation as well. So no option of defining a waypont at a distance from a fix and then flying to the base fix, as the ident will now give the offset coordinate. Not sure if this is also a real life limitation.First time I played around with the functionality was flying into EKRK via TNO. There is a level restriction of max FL70 20 NM prior to TNO. So I offset TNO by 20 NM on the radial I was flying inbound along, and I could now enter 7000 on the V NAV page and get the needed VS - simply lovely
Trying to insert TNO as the next waypoint after the offset version then gave trouble. Fair enough it's a VOR anyway so I could navigate via that, or insert the co-located RNAV waypoint RK361 in this case.
When I then tried to insert the ILS21 via TNO transition approach, that also started at the offset point 20 NM off from TNO.
In the end I gave up on finding a way of inserting it all and simply flew the procedure using VOR1 with no overlay from the FMS.
From my playing around, it seemed that an alternative option was to create a user waypoint, but as those are only definably via coordinates and not RAD/DIS it is quite some extra work. Didn't try it at the time, but I guess I could also have defined the custom points via the joystick.
Making 2 different RAD/DIS points with different offsets from the same "base waypoint" also seems to be impossible (was trying to see if I could add a couple of "checkpoints" on a DME arc).So in the end to summarise everything - I wonder if RAD/DIS is working as intended. With the way it renames the offset waypoint I would guess that the base waypoint would still be usable in the real world.
(Also have had some weird behaviour when deleting an offset waypoint and the offset name sticking with it if you try to insert the base waypoint again, but don't have the specifics yet to give a full description.) -
@Avionic Can you not insert a reporting point, a certain distance away from the waypoint, instead of offsetting the waypoint itself?
@ploodovic I will check it later in the sim, but AFAIK reporting points can unfortunately not be based on fixes which are part of the route, as it is for defining when you pass a radial/abeam a point off to one side.
Looking at the manual, options for reporting points are “POINT ABEAM STATION” and “POINT OF INTERSECTION WITH RADIAL”, and I believe the CDU blocks you from inserting one of the route fixes as a base for a reporting point (as it would then always end up being exactly the same place as the base fix).
I guess I could fx have done a reporting point from MIKSI with radial 236 but to figure that out, I first need to start drawing, where the RAD/DIS method otherwise allowed me to do it with no external tools.
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@ploodovic I will check it later in the sim, but AFAIK reporting points can unfortunately not be based on fixes which are part of the route, as it is for defining when you pass a radial/abeam a point off to one side.
Looking at the manual, options for reporting points are “POINT ABEAM STATION” and “POINT OF INTERSECTION WITH RADIAL”, and I believe the CDU blocks you from inserting one of the route fixes as a base for a reporting point (as it would then always end up being exactly the same place as the base fix).
I guess I could fx have done a reporting point from MIKSI with radial 236 but to figure that out, I first need to start drawing, where the RAD/DIS method otherwise allowed me to do it with no external tools.
@Avionic Let me first say, that I don’t have the Starship (yet), so I’m merely spitballing here. It makes sense that you have to use a reference point not part of the flight plan, when the alternatives are point abeam and radial. That obviously can become a problem, if there are no appropriate points to reference.
In your specific case, as you say, a solution could’ve been, to work out, at what radial toward MIKSI did your flight path intersect, when the distance to TNO was exactly 20 Nm, or whatever distance you’d prefer. It would require some extra preparation, for sure, but I think it could be a fun exercise nonetheless. Love these questions, where you have to use a little bit of creativity.
Cheers, and good luck!
