If you look at the airways which exist in the lower airspace (below FL200 or 250?) in or out of the UK you see that DCTs are very hard to avoid – especially if you look at them carefully i.e. see their directions
and as Tom says, ATC works with the concept just fine.
I would avoid manually created DCTs unless you know what you are doing. One example of such is here. There could be some military area (notam activated or not) on that bit of the route which was hacked together with a string of DCTs
and nothing will prevent you filing it. But ATC won’t let you fly it on the day.
But ATC won’t let you fly it on the day.
And if ATC will not let you fly it and vectors you around it, it will add to your ATE. Will you then have enough endurance to reach your destination, fly to your farthest alternate and then for 45 minutes?
This is one reason for me to avoid DCTs unless I am pretty confident I will be able to fly that route.
ATS routes (airways) may be a thing of the past, but free route airspace is a thing of the future in much of Europe – in other words not the present.
just a warning – some countries (or at least one – CZ) are not allowing DCT when filling flight plans – you get: ROUTE165: THE DCT SEGMENT BNO..VLM (72 NM) IS TOO LONG FOR LKDCT:000:165. MAXIMUM IS 0 NM [LK2A] message. In a real life you´ll get number of DCTs while airborne but the flight plan must be filled following airways and the validation principles at CFMU.
Yes. In my last post is an example of getting around a MAX DCT of 10nm in some part of France.
A country with a value of zero must have CAS to surface around every airport and then every airport will have sids and stars. Albania is one of very few cases.
Aviathor wrote:
Will you then have enough endurance to reach your destination, fly to your farthest alternate and then for 45 minutes?
Such a detour seldom adds more than 5 minutes, so if that is going to kill your fuel calculation, then you’ve been pretty tight before.
And filing airway routes doesn’t mean you cannot get reroutes, which mess up your fuel calc.
Unless your strategy is to deliberately file a very high overhead airway route and then hoping to get a shortcut (which may or may not work; you tend to get shortcuts only within sectors, it’s harder to get shortcuts that change the sectors traversed, and your high overhead airway routes look like they’d lead you into the wrong sectors).
Aviathor wrote:
in other words not the present.
How do you know, since you never try? Look at the map – it’s very much a reality already. Even die hard non FRA ANSP like skyguide have added many allowed DCT – check the RADs.
Anyway, I hope you’ll never have to go to Hungary – there are no airways there anymore. Or to Poland, unless you have a very good oxygen kit (almost no airway below ~F200) or have booked some in air refuelling with NATO.
Peter wrote:
Albania is one of very few cases.
and Czech republic – we can´t have IFR approach to uncontrolled airport – at the moment. But things are moving even in this near Albania country…. ;-)
I did a bit of research on DCT segment length – actually there are more countries/sectors than Albania and CZ – for details see Appendix 4 at the Eurocontrol RAD – there is an xls file.
hopefully the list will be shorter and shorter.
Peter wrote:
A country with a value of zero must have CAS to surface around every airport and then every airport will have sids and stars.
My understanding is that the DCT limit enroute is distinct from the DCT limit to an airport. The former can be zero even if the latter is not. And vice versa.
Airborne_Again wrote:
My understanding is that the DCT limit enroute is distinct from the DCT limit to an airport. The former can be zero even if the latter is not. And vice versa.
Correct.
tomjnx wrote:
And filing airway routes doesn’t mean you cannot get reroutes, which mess up your fuel calc.
Indeed. There is good example of that here.
In this case IIRC the DCT route proposed by the autorouter proposed a more direct routing between Stuttgart and Erfurt, but my actual route would have been the same. In terms of ATE it was pretty much the same sa my ETE.
tomjnx wrote:
Unless your strategy is to deliberately file a very high overhead airway route and then hoping to get a shortcut
My routing is a balanced approach between airways and directs. Because of some awkward moments using directs, I tend to use them carefully
tomjnx wrote:
How do you know, since you never try?
Who said I never do?
tomjnx wrote:
Anyway, I hope you’ll never have to go to Hungary – there are no airways there anymore.
I certainly hope I will indeed go to Hungary. Thanks to the present forum I am very well aware that they have abolished the airways and I look forward to filing lots of DCTs.
What I do not understand, @tomjnx, is what I perceive as your aggressivity. Why on earth are you so passionate about this?
