Does really optimal route generation deliver a shortest route, comparing to filing “something reasonable” and pushing solidly for shortcuts?
In flying with the very optimised Autorouter generated routes for several years, I think the answer is NO. IOW, you would get a similar “distance flown” result by filing something which is roughly similar and then pushing ATC for shortcuts.
The point is that I don’t think ATC care at all what really clever route you filed. And this is likely because they don’t [readily] see what you filed! There are many stories from ATC, over years, that all the ATCO sees of your route is a straight line running right across his whole sector, so all the cleverly optimised waypoints you have filed within that sector are lost. And in general you will have no idea where his sector starts and ends. Can any ATCO confirm the current situation on this?
Within his sector he will route you tactically using radar separation (the standard way in most of Europe) or (if things are empty and relaxed) just give you a DCT right across his sector, or (even better) perhaps to a waypoint somewhere in the next sector but for that he has to make a phone call. IME this is clearly how it works.
A really obvious example is say from UK and across Belgium. Whatever you file you always get KOK-MAK-LNO right across Belgium and – at the usual FL100 – they completely disregard the filed route.
Basically, where you have an “airway” or just a chunk of CAS, and within that is a “standard route”, then no matter what clever route you have filed which lies within that “airway’s” width, ATC will tend to just give you the standard route, unless you keep asking for a shortcut.
And whatever route you have filed, there are usually cases where you really want to cut some corner, and you have to ask for a shortcut, and sometimes keep asking. Often this is not possible due to various rules which you can’t possibly know about (e.g. AFAIK a shortcut is not possible across a piece of another country which happens to stick out into your proposed route) but quite often it is really quite obvious from the “tone” that you aren’t getting it because they can’t / don’t want to make the phone call to coordinate (and there are places where this happens regularly).
For years, many pilots have said what I am suggesting here i.e. the most perfect route filed doesn’t get you anything on the day.
I agree but routing software which isn’t up to the task of generating optimised routes can give very strange results. E.g. for LDVA to ESKN FF gives 905 NM route that goes over Hungary, Slovakia and Poland while AR gives 811 NM route which goes (properly) over Austria and Germany. So once you start in wrong direction no ATC can correct it and no shortcut will help you. At least now you can fix it in FF by choosing waypoints but AR gives it out-of-the-box.
Yes; I was assuming that the route is roughly right
Presumably the lack of response is because almost everyone is using the Autorouter, and nobody wants to appear to be less than 100% appreciative of such a useful tool, but it should be a valid operational question.
ATC input would be interesting too.
My experience is that its better to file a proper route via airways rather than a shorter route hacked via DCTs. I have had many cases, esspecially in Germany where I got a new route assigned (either when on the ground or airborne) because ATC wants you to fly via waypoints that they know.
A couple of months back in Germany (EDDN) it took me 10 minutes with Delivery to copy a modified route over the radio, getting all the waypoints spelled out etc.
After being handed over to Munich Radar I got a 200 NM DCT which basically skipped all the waypoints I had previously copied …
That’s been my experience also.
The more a clever route you file the more ATC tend to not operate it
In the current wx we are having in much of Europe, nobody is doing much flying anyway…