Simviation Forum - Traffic Patterns

Feb 27^th, 2006 at 8:22pm

cheesegrater Ex Member

What kind of traffic patterns do airliners fly? I know general aviation aircraft fly those rectangular patterns. Is it just a straight in approach for an airliner? What if they cannot land at the moment and have to stay in the air? I suppose it depends on the area, as big cities may have many airports in close proximity.

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Reply #1 - Feb 27^th, 2006 at 8:52pm

beefhole Offline
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Well, it depends-is the airliner flying a STAR (which it most likely is) or is it being vectored in directly by ATC?

In FS, ATC will put you in a traffic pattern-if you approach Atlanta from the west and runway 27R is active (landing to the east), ATC will put you on a downwind and have you turn on a base for 27R. In real life, when STARs are being used, patterns are generally not flown-the aircraft flies to a given point where they begin their final approach. However-if, for example, the tower decides to change the runway just as you turn on final (which has happned to me once before in FS, more times than I care to remember IRL), you will be told to "make left traffic for runway 9L", etc. In that case, airliners DO fly a normal pattern, albeit much higher and further out Wink

I was pretty much wingin that, if anyone can give something more accurate please do.

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Reply #2 - Feb 27^th, 2006 at 10:01pm

Brett_Henderson Offline
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That's pretty close, but nothing is carved in stone. Standard approaches (STARS) can start as far out as 100nm and there's always one, if not a few hold fixes. There are usually a set of STARS (or one STAR with a few versions) for each active runway to accommodate traffic approaching from all directions. When spacing becomes a problem.. ATC asks a plane to hold..or.. can expidite him from a point on the STAR directly to the runway... or alert him that he'll be flying vectors period (which could very well include a downwind/base).

If everything goes well.. the whole point of STARS is to make it all efficient.. It's awfully expensive for a 777 to fly pretty much to an airport and then fly a few miles out and back in some sort of "jet-sized" pattern.

I was on a US Airways Dash-8 into Pittsburg last year and I swear we flew a tight downwind and then the turn to base/final was all one motion.. barely lining up with the runway at the numbers. I'd have loved to have heard THOSE vectors..

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Reply #3 - Feb 27^th, 2006 at 10:07pm

beefhole Offline
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Quote:

Standard approaches (STARS) can start as far out as 100nm and there's always one, if not a few hold fixes. There are usually a set of STARS (or one STAR with a few versions) for each active runway to accommodate traffic approaching from all directions.

Right Brett, I was simply trying to point out in my post that you almost always head from a fix to the runway, as opposed to being vectored to the runway by ATC.

I've also had a Dash flight fly a pattern like that, on a turbulent winter day into PHL.

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Reply #4 - Feb 27^th, 2006 at 10:39pm

Brett_Henderson Offline
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They must have a reputation as pretty nimble aircraft.. able to duck in quick and get off the runway.. Grin

Most STARS have different criteria for turbo-prop planes..

I'm gonna go find one and post it..

EDIT: Here's a good one. Plenty of holds and info..

http://204.108.4.16/d-tpp/0602/00655CINCE.PDF

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Reply #5 - Feb 28^th, 2006 at 4:44am

C Offline
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Quote:

I swear we flew a tight downwind and then the turn to base/final was all one motion.. barely lining up with the runway at the numbers. I'd have loved to have heard THOSE vectors..

Who needs a base leg anyway. The last time I flew a base leg was in 1999! Grin

(By way of explanation, the circuit/pattern we fly is an oval) Wink

Quote:

EDIT: Here's a good one. Plenty of holds and info..

Lol. There's a good one I saw for one of the Norwegian airports (I think). The whole TAP was like a spiders web of holds and fixes! I'll see if I have a copy I can scan... One of the reasons I'm happy not flying transport aircraft just yet! Grin

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Reply #6 - Feb 28^th, 2006 at 8:05am

Nexus Offline
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a STAR doesn't really have anything to do with the pattern, as seen by the Arrival procedure posted by Brett, and there were some nice holds there Grin

The pattern is usually described on approach charts, from the IAF to the FAF.

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Reply #7 - Feb 28^th, 2006 at 10:41am

Brett_Henderson Offline
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Quote:

The pattern is usually described on approach charts, from the IAF to the FAF.

A cessna 172 isn't going to start his arrival at Cincinnati some 15 miles NE of Columbus (110nm out) Tongue

... and a 777 isn't going to fly an approach chart that has him turning abruptly 90 degrees at the outer-marker Wink

The only approach chart that I can think of that even sugests a traditional pattern would be a VOR-A where you look for the airport and then circle to land (pick the best runway(maybe fly a leg or two (or three)) of a pattern).

If the tower doubts that they can get a jet to the runway, relatively straight in.. they'll make it hold somewhere along the STAR.

If a 172 intends to land at a busy airport, he will file (or announce(or be given)) a published approach, but he'll be vectored all the way in. IAF / FAF and all that stuff (and missed procedures) and a pilot's responsibility to fly it, would matter if radio communications were lost. I can't imagine a scenario where a small, GA plane would just be cleared to land and decide for himself to follow the plate. Same thing for the 777 (if he even could).

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Reply #8 - Feb 28^th, 2006 at 11:40am

Nexus Offline
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I thought the original question was about commercial airliners, not general aviation.
Therefore, what the little c172 does is rather irreleveant in this case

But you're correct in your assesment, but itäs not what I had in mind Grin

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Reply #9 - Feb 28^th, 2006 at 11:58am

Brett_Henderson Offline
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Yeah.. original questions seem to fade quickly around here..lol

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