Do not fly STARs

[Stein Carlsen]

Hello all,

Just wonder:

Don't STARs being flied in real life? I ask because I watched Flightradar24 and watched the approach to OSL (ENGM) in Norway for a while. At the same time, I had the relevant STARs up. What I observed was that no (NO) aircraft followed a STAR down towards the current runway. There was some traffic, and the planes seemed to be directed by ATC so that the approaches went smoothly.

There has been some discussion here about whether ATS should change the stated flight plan, especially with regard to the stated STAR. I now saw quite clearly that it was absolutely necessary to get a good traffic flow.

I guess the same will apply to Vatsim.

Regards

 

Edited June 26, 2022 at 12:44 PM by Stein Carlsen

[Trevor Hannant]

You should always plan to fly a STAR, and CTR should also assign the STAR you're to follow however if suitable, APP (or CTR if covering top down) will likely vector you off it for flow and/or expediency.

[Magnus Meese]

Oslo uses PMS - Point Merge System: https://www.youtube.com/watch?v=rC_X6t_Rbq4
Direct routings to the four merge points is standard.

In addition to this, ATC will always expedite aircraft (directs or vectors) when possible, the goal is to safely ensure noone flies for longer than strictly necessary. Most places the full STARs are only flown when the airspace is reaching max capacity.

 

[Stein Carlsen]

Thanks for all your answers.

Regards

[Tobias Dammers]

21 hours ago, Stein Carlsen said:

Hello all,

Just wonder:

Don't STARs being flied in real life? I ask because I watched Flightradar24 and watched the approach to OSL (ENGM) in Norway for a while. At the same time, I had the relevant STARs up. What I observed was that no (NO) aircraft followed a STAR down towards the current runway. There was some traffic, and the planes seemed to be directed by ATC so that the approaches went smoothly.

There has been some discussion here about whether ATS should change the stated flight plan, especially with regard to the stated STAR. I now saw quite clearly that it was absolutely necessary to get a good traffic flow.

I guess the same will apply to Vatsim.

Regards

 

OK, so the way it works at most major airports is this:

• The flight files a flightplan with or without a STAR (this depends on local regulations - some places want you to file a STAR, some don't)
• During the descent, ATC clears the flight for a STAR. If one was filed, then that STAR or an equivalent one for the current airport configuration, will often be assigned, but this isn't a requirement.
• The flight then proceeds towards the entry point of the STAR, and possibly onto the STAR.
• Eventually, ATC overrides the STAR, either by issuing vectors, or by reclearing the flight for a transition. This may even happen before the flight actually enters the STAR, but it can also happen at a later stage.
• Finally, ATC clears the flight for an approach, and hands them off to Tower once established.

Depending on the situation, a flight may end up flying a large portion of the STAR, but it is pretty rare to fly the whole thing as published, and in most cases, you get taken off early, because it's more efficient. The STAR still matters though, because it defines safe defaults for lost comms and excessive controller workload situations - once you're cleared for the STAR, ATC knows what you will do if they don't do anything, and they can keep you on the STAR while handling other traffic, and then get back to you to sequence you in. The same goes for transitions: once you're on the transition, you will typically fly an S-shape ("trombone"), which is a somewhat inefficient, but sensible, default, and the "S" shape makes it so that ATC can fine-tune the sequencing by issuing simple DIRECTs within the transition. The great thing about clearing for STARs, transitions, and "AFTER X PROCEED DIRECT Y" style shortcuts is that, unlike vectors, they are not time critical, so a controller can plan out an entire sequence, and then just issue instructions one by one, without having to time them precisely.

This is a versatile system: when it's busy, it allows ATC to manage workload and create efficient arrival sequences; and when it's calm, they can just vector you straight in. And in the rare lost-comms case, that one aircraft whose entire radio system failed at once can still get down safely by following the lost-comms procedures, and ATC knows what they will be doing and can work the other traffic around them.

[Stein Carlsen]

Thank you for a complementary and good answer.

Regards

[Mateusz Zymla]

Also, if the traffic load permits, you don't even need to be assigned STAR. You may immediately receive Approach instructions, let's say, "Expect ILS approach RWY xx, proceed dct yyyyy", where YYYYY is already an IAP point, so there's no point in assigning STAR (as all the points have been literally omitted). That's pure ATC decision, as long as you know what to do after your last point in FPL.

Sometimes, when there's a chill ATC session, I can even give in the Departure clearance "Departure runway xx, initial climb FL200, direct YYYYY" where YYYYY is an FIR exit point 🤪. If there's no traffic, airspace structure allows it, he is within Radar Coverage all this time, there's no point in flying all the SID/STAR, really. They're only created for Airspace/Terrain avoidance and traffic flow.

Edited June 30, 2022 at 04:57 PM by Mateusz Zymla

[Tobias Dammers]

1 hour ago, Mateusz Zymla said:

They're only created for Airspace/Terrain avoidance and traffic flow.

Also noise abatement, but I'm sure our simulated citizens will live.