For the love of intersection departures

First of all – a confession, I fly (IRL) props, and in the sim don’t really have much interest in the A380’s/777’s (too risky that I might fall into space at those heights).

The props don’t get much love in the sim, often forced into painful ‘no intersection departures allowed’ sequencing by ATC between a bunch of heavies that A) would never happen IRL (try taking off in a 208 immediately after a 380 departure and you’ll do somersaults in the sky) and B) is horrifically inefficient in the departure flow.

In real life:
At almost all major ports I fly to, intersection departures are the most common set-up, with anything ATR72-smaller using one intersection, 737/320 sized (generally/weight dependent) using a different one, and anything larger going for the full length. IRL – watching this setup can be beauty in motion. The controller, with an aircraft arriving at the 5nm marker, can clear me for takeoff, a 737 to line up and wait, and a triple to do the same (yep 3 aircraft on the runway at the same time!). I’ll depart and swing north (often before opposing threshold), the 737 is then cleared and swings south after reaching minimums, and the triple then departs straight out with plenty of clearance for the arriving aircraft (any combination of these SO/N/S combinations work too (airport dependant).

Usually the only exception to this departure flow is crosswinds/windshear/low visibility, but departures would be set up like this 90+% of the time.

Here is what it looks like in action:

The issue in IF:
Unfortunately when things get busy, the default for IFATC seems to be ‘no intersection departures allowed’ – and I understand the perspective, having everyone in one long line is easier to manage when you are setting up a basic, one-in, one-out principle - and you can hand out violations for queue-jumpers.

The problems are that creates a bunch of unnecessary congestion (when you could be getting 3x the departures), with an added layer of misery is as an airport switches controllers from a more confident (with intersections), to a less confident (no intersections), the ‘no intersection departures’ comes and goes. I had it the other day, holding at the intersection with a confident controller who had great flow management – the ATC switched and suddenly there was a new ATIS with no intersection departures allowed, and those of us in departure sequence either went ignored or had to pushback into the traffic flow (the controller had no interest in picking up anyone in the current departure flow).

The fix:

  1. IFATC is actually already clear in the guides that the ‘no intersection departures’ should almost never be used unless intersections are going to block major arrival exits. It would be great to actually have this blocked at major airports where that problem is (almost) never an issue - that would stop fresh, still-learning-the-ropes IFATC from taking the easy route, but also adds realism and builds departure capability.
  2. Adding an ATC command ‘shortened’ to taxi/takeoff requests. This could go after selecting the runway and builds good communication between pilot/ATC. Here is how the conversation would go:
    Pilot: “Request taxi to runway 23L shortened”
    Ground : “Taxi to runway 23L shortened, contact tower when ready”

Pilot: “Ready at runway 23L shortened, departing north”.
Tower: “Cleared for takeoff runway 23L shortened, departure to the north is approved”

Shortened is a common global ATC term for not using the full runway length, and as far as I can tell, wouldn’t complicate many other things in the sim – it would just improve communication. IRL, you would include a taxiway hold position in those readbacks – but for IF, lets walk before we can run :) .

This is more of a story than a feature request, because, in theory, good ATC management would mean there isn’t really a need to add the feature (except to improve the status-quo/add realism). I also get that there are queue-jumpers out there, which is probably the main reason ATC put the remark into ATIS – but that’s why we have departure sequencing.

So more of a note to the world to A) share some love for us prop pilots (we are more than just a windmill that fell over), and B) make the most of intersections, they exist for a reason and would bust rather than add to a lot of the congestion we see.

What’s your thoughts on intersections? And see you in the friendly skies!

Flyspikes

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Very well-spoken! I agree with everything you said—intersection departures can be a life-saver on both sides of the radio. As you mentioned, they can greatly improve efficiency if used properly and are used that way in the real world as well. Lighter aircraft can get in the air much faster than heavier aircraft, so it’s also a perfect strategy for clearing a long departure line.

If you ever find that intersection departures are not being allowed when maybe they should, I’d recommend messaging your controller here on the forum; sometimes, controllers don’t see the room for intersections that pilots do, so it can be a great learning experience. Keep in mind that the ability to realize those inefficiencies and take action on them is something that comes with time and experience which is exactly why our controllers get better every day. It’s quite easy for newer controllers to think of intersection departures as a negative and inefficient thing; this topic outlines exactly the opposite and can definitely be shared with controllers if appropriate.

As for the shortened taxi request, that’s an awesome idea. Once you reach Trust Level 2 (Member) here on the forum, I’d strongly encourage you to create a #features request as that’s how support for certain features can be best measured. Keep positively contributing to the forum and you’ll get there in no time. For more information regarding the trust level system, take a look at this topic.

Thank you for this message! It should prove to be very educational and thought-provoking amongst the controlling team and pilots. Feedback is a powerful tool and is always happily accepted. I hope you start to see progress with the use of intersection departures; you’re also always welcome to join IFATC if you’d like to make a change from within or simply control on the Expert Server. See you in the skies!

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I honestly stand by this statement 10000%! It doesn’t affect the simulator, but affects the people positively when they are in their planes, and also the ATC gets satisfied with the result you mentioned here @Flyspikes! Like 3 planes taking off in some minutes is actually very efficient and the stress would likely be removed. But of course, this will eventually come to the controllers as well, they just need to get the optimal confidence and the time will only tell!

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It would be great if we were able to have these sort of sophistications from ATC, I agree. Another example would be an ability to accommodate suitable runway requests for props when the main landing runway has a crosswind thats outside limits for a Q400.

Unfortunately these sort of things seem to be dependant on having a
more experienced controller and a generally quieter traffic flow. I notice that when things are busier the default arrangements are usually adopted, including the giant conga line for arrivals.

I hope that IFATC trainers can take up these issues as development opportunities and to enhance the realism going forwards.

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Supervisors look out for this regularly and provide feedback to controllers when it’s used improperly. You’re correct, it is extremely rare to see it used. Places like TNCM are a good example of an airport it should be used at.

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I’m all for letting a Dash 8 go out in front of a line of heavy departures, if I had the ability to assign a departure heading. I have had too many times where the dash 8 flies runway heading for 5 miles before making a turn. If I send airliner after, they are going to eat the dash up. On the other side, I have seen many heavies that engage LNAV after departure and make a 90 degree turn at under 1000 feet because the SID would normally have you fly runway heading until XXXX feet the turn direct XXX way point, but the IF LNAV system doesn’t handle this and it is the pilots responsibility to fly it.

The ATC commands need to be updated before we will see a real change. The controller is at the mercy of hoping the plane will turn out of the way, and if they don’t, there is no way to correct the problem unless there is a radar controller present that is handling departures.

I would love to be able to operate an airport the way you described, but it’s not a realistic option yet in my opinion.

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Good points - and that’s pretty much how the SIDS work in real life too - the change is made once airborne(in case there are any issues). Here’s how the exchange would go IRL:

Pilot (light): Auckland tower, Barrier 3 18 ready for takeoff at hotel for 23L shortened. Departing north.

Tower: Barrier 3 18, cleared for immediate takeoff - expect plan variation.

Pilot (light): Cleared for takeoff, expecting variation for Barrier 3 18.

Pilot (320): Auckland tower, New Zealand 5 15 ready for takeoff at India, for 23L shortened.

Tower: New Zealand 5 15, taxi into position and hold, caution the departing windmill.

Pilot (320): Position and hold, for New Zealand 5 15.

Tower: Barrier 3 18, turn right heading 350, departure is 118.7 - see ya.

Pilot (light): 350 for Barrier 3 18, departure on 118.7 goodbye.

Tower: New Zealand 5 15, cleared for immediate takeoff runway 23L, expect plan variation.

Pilot(320): cleared for takeoff, expecting variation, New Zealand 5 15.

Tower: New Zealand 5 15, cancel departure plan, proceed direct to KAPAI, departure is 118.7 goodbye.

Pilot(320): Direct to KAPAI, departure on 118.7, have a great day.

(And continue down the conga line)

In IF
ATC can already use a similar flow, it would just have to be heading based. And as soon as the departing aircraft is airborne, give the turn heading, and as soon as the aircraft commences the turn, clear the following aircraft for departure.
.

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Agreed on all points.

I think the biggest reason why controllers like to use “no intersecting” is because they think it helps them, when in reality it really doesn’t if an aircraft is ready to depart and an intersecting spot, it’ll get them out quicker than waiting on Joe Slow at the end of the runway to figure out how to start an engine.

The biggest issue with intersecting departures I see is that people typically don’t use it to help expedite the line for the controller, but rather use it as a way to cut the line. While this is hypocritical to my point of helping get people out quicker, I also pay attention to line cutters.

If you are in a line and several aircraft ahead, I’ll make note of the aircraft you “were behind”, and then wait until they’ve gone before I let you out. This helps me not slow the process, as well as not give an impatient pilot a quick way to cut the line.

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Great topic and thanks for surfacing the need for more intersection departure allowances. It can be a great way to expedite GA or take advantage of alternating departure directions.

Unfortunately your solution with the verbiage “Shortened” wouldn’t be correct. This is only to be used for permanently or temporarily shortened runways that hasn’t been reflected in an appropriate publication. An example would be runway construction on a displaced threshold which temporarily shortens the usable runway available to pilots.

I believe the simplest solution is a simple request for an intersection departure at the time of taxiing. An upcoming ground feature, hinted at here, will make a lot of this possible so that specific instructions and runway intersections can be used with less ambiguity.

Without giving too much away, stay tuned! More pilot options like this are high on my list and I hope to see it introduced sooner than later.

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