Two parallel runways

I have a question regarding the control of the airport with two parallel runways. For example, at EGLL, if the wind conditions permit, can I use at the same time runways 27R and 9R for arrivals and departures, and if yes, what should be minimal distance between runways for that kind of operations. I understand that at EGKK it would not be a good idea, but the EGLL runways are quite apart from each other.

i normally when i control i only use 27 R/L for arrivals and departure or viceversa

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You can do it. Similar operations are done in the real world at other airports. Its actually airport specific and depends on how far apart the runways are (amongst other things).

I’m not familiar with EGLL so I cant comment exactly on it.

I can however explain that Sydney airport YSSY does it on occasion. The two parallel runways are over 1000m apart. For noise abatement purposes, late at night or early mornings on weekends, when the wind is calm, YSSY utilises 16L and 34L.

All landings are on 34L (approach is over the oceabm then over a single suburb on a peninsula then over a bay). Departures are then off 16L (takeoff over the bay, left turn through the heads out over the ocean). This opposing configurations happens and does not need a ‘separation’ between the opposing traffic (eg one can be on a short final on 34L while another is departuring directly next to it on 16L). Large aircraft that cannot depart from 16L still depart from 34L between the arrivals.

So in short, yes it can be done at airports. Can it be done realistically due to the set up, noise procedures etc, or is it ever done it real life at EGLL… I’m not sure.


No. When using parallel runways, you must use the same direction for takeoffs and landing. Either both 9s or both 27s.

I know of no airport in the world which would allow inbound traffic in the face of outbound traffic. The possibility of incursions would be astronomically high. [I stress again that IRL, there are SID/STAR arrivals/departures which do not exist in IF. They are different.]

I realize on TS1 pilots don’t want to go around, but you as ATC should never facilitate it.

(If Sydney really does this in real life, I’ll take his word for it, but remember planes in real life are flying SID/STAR departures/arrivals, something we do not have in IF.)


In DXB it’s possible since I have seen my plane a A330 landing while an A380 takes off in same direction. (My plane lift offs at the same time parallel a A380 touches down) (I know I reversed by mistake but it’s still the same)

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This is a tad unclear. They were facing the opposite direction?

It is never done like that at EGLL in real life. Either departures and arrivals are both from the 27 runways or both from the 09 runways, never a mixture.

On IF as you say in calm conditions theoretically it could be done, but tbh I think you would be setting yourself up to a lot of complexity in controlling it, and lots of problems with users not understanding what you are trying to do. Added to that you would create a lot of conflicts with departing and arriving traffic which could be a big problem.

My advice, FWIW, just stick to arrivals and departures both from the west or the east. The simpler things are the easier it will be for you and the other users.

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In my experience at EGLL when 09’s are in use then 09R is used for departures and 09L is used for arrivals. When 27’s are in use I believe they tend to alternate them with a change over about noon. So et,hing that would be tricky to set up in IF!

However they will only use 09 or the 27 not a mixture.

No it was in same direction

That’s what I figured. That’s common. For instance, at KATL, when using the 26s, planes arrive on 26R, depart 26L. If using 8s, depart 8R, arrive 8L.

Never arrive 26R, depart 8R, which is what he’s asking.

Exactly what I said

Okay. As I said, your phrasing was just a tad unclear. Just wanted to clarify. Sorry.

@Tim_B yep, I was referring to the two different runways, conducting opposite direction operations. The flow of traffic is opposing, but they are on runways that are about 1000m apart and have a specific left hand turn at 500 feet after departure on 16L to again further avoid any conflicts.

However, some real world airports can, and do, conduct opposing operations on the same runway. It is definitely not common, and is rarely used, but it does happen. A simple example is KSAN. Whilst most people are of the belief that only runway 27 is used at KSAN, that is incorrect and only runway 9 actually has ILS installed. Often visibility gets too low (early morning) to utilise runway 27 as the final approach fix is quite a distance out. As a result, the ILS approach on runway 9 is used. However, aircraft over a certain weight, 767 heavies with a large cargo load for example, cannot sufficiently depart using runway 9 due to the slope of the terrain, and will depart using 27, against the flow of traffic. It is EXTREMELY rare, however it can happen. This results in opposing operations and causes delays due to the difficulty in maintaining separation minima.

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In IF, we depart 33, arrive 15 at Aspen.
IRL, departure and arrival plates are in use, which can prevent incursion.

However, with the current-state features of IF, I would advise against attempting this. I promise, IF pilots aren’t studying their charts as they approach or depart.

@AR_AR: They exist IRL, fine. Would you as an IFATC use them, except in special cases like KASE?

No, in IF this just complicates things. We also have pilots that can’t tell right from left, so that would cause issues.



So, we can find all the examples in the real world, but to the question as originally posed: In IF, no.

Well, you could do it in IF. I don’t think it has ever been attempted though.

I have seen it happen at Aspen on IF…not every time, just once or twice!

As I mentioned earlier, KASE is a special case in IF. We depart 33, arrive 15.

We do not use 27 and 9 simultaneously at EGLL.

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