Minimum distance inbound traffic for take off on same runway

The title is a bit cryptic, but that’s because I’m having a hard time formulating my question.

What is the minimum distance of inbound traffic for outbound traffic to be allowed to take off on the same runway?
How many nm away from the threshold can a landing aircraft be for another to be allowed to take off?

I hope my question makes sense.
I’ve searched but not found.
When I missed another topic about it, than I’m sorry.

Jan

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Only one aircraft can be on the runway at a time. If one is taking off, it’s wheels have to be off the ground when the arrival aircraft touches down. A good separation is 3 miles.

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3 miles. Got it. Thanks!
Oh, and when two aircraft are departing one after the other, how much time or how many miles must be between them? Other than Flight of 2.

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As soon as the wheels are off the ground the other one can go! If it’s about to rotate (outbound traffic) go ahead and clear the other aircraft to takeoff as it will be off the ground by the time the other aircraft gets there!

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Thanks!
I’m asking for situations without ATC.
So lining up and wait is only allowed when the wheels of the first aircraft are off the ground? Or is it allowed to line up and wait earlier?

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No, what @Furtive_masstwofourf said about the departures separation is wrong.

image
(according to the FAA).

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You can position and hold once the first aircraft has started rolling just keep in consideration if you have an aircraft on final.

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It that 60/90/120 seconds from wheels off the ground of the first aircraft to starting to roll of the second aircraft? Or from the first aircraft starting to roll to the second aircraft starting to roll?

Once the aircraft starts to roll. The timing is based on aircraft size and how much wake turbulence they are producing. So you want to allow enough time for it to dissipate before sending your second aircraft into it.

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In general:

Seperation of arriving aircraft is based on distance

Seperation of departing aircraft is based on time.

It’s not realistic (and wrong) if you clear an aircraft for takeoff as soon the other aircraft infront of you took off.

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Hey where did you find that in the FAR/AIM I looked this morning and couldn’t find it.

As controllers here on Infinite Flight, we base our separation on what @Furtive_masstwofourf mentioned.

The reality is this- we don’t have any wake turbulence or any other sort or factor in the sim that would make the waiting time as outlined in .65 viable. There’s absolutely no point in having aircraft wait for 2-3 minutes (depending on criteria) for no reason. Even Tyler mentions this in one of his tower videos, if you’ve been paying attention to them. ;)

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^^ Bingo! Although, we should start following those separation guidelines if wake turbulence gets added

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If wake turbulence was ever added, then I’d happily follow those guidelines. For now and the foreseeable future, we’ll just work with what we got. ;)

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We keep it VERY simple here. We have no wake turbulence on Infinite Flight so there was no sense in in implementing that separation requirement. Here is our Infinite Flight separation:

Departure VS Departure:

The first departure must be airborne prior to the second beginning takeoff roll.

Departure VS Arrival:

The departure must be airborne prior to the arrival crossing the runway threshold.

Arrival VS Arrival:

The first arriving aircraft must be clear of the runway edge and committed to the exit prior to the second arrival crossing the runway threshold. (if touch and go it is the same as “Departure VS Arrival”)

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Not quite. You can’t have an aircraft line up and wait to satisfy your wake turbulence hold. Wake turbulence is a 2 or 3 minute hold.

2 minutes: Same departure point (waiverable if proceeding dep was a large)

3 minutes: intersection or opposite direction

The rest is simply IFR separation or Category separation.

VFR departures are either 3000,4500, or 6000ft and airborne, depending on the category of the aircraft.

IFR is 3 miles, 5 miles behind a formation or 7 miles when it’s faster behind a slower.

That’s the quick rundown of real world separation.

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Thanks @Tyler_Shelton!

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Thanks for the clarification. I know it’s not standard practice, but if there is no traffic in the area is it wrong to line up and wait an aircraft to start the wake turbulence clock?

Yup, still not allowed. You can find it in the FAAO 7110.65 :)

I was looking at the 7110.65 under section 3-9-4. LINE UP AND WAIT (LUAW). I didn’t see anything about it though. I’m here to learn brother so thanks for the inside info.

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