Kieran17

I'm doing some curiosity research on flight progress strip placement and I'm wanting to find out what processes are used in other towers around the world with a couple of quick scenarios, they are primarily geared toward towers using paper strips but works for electronic strips as well:

Scenario one: Arriving aircraft has been cleared to land, the strip is in the runway bay. Departing aircraft is cleared to line up and wait behind. Do you place the departing strip above or below the arriving strip?

Scenario two: Two departing aircraft are lined up on the runway, aircraft one is at full the length, aircraft two is at a mid point intersection. Is the mid point intersection departure above or below the full length departure?

Bonus points if you include your medium (paper, electronic, strip-less and just wanted to join in) and reasoning...


Thanks Everyone.

poporange

That is an interesting topics here

Tarq57

1) the landing aircraft is at the bottom of the bay, the lining up behind a/c is immediately above it.
2) the inset (first to go) departure is at the bottom, the full length above it.

Reasoning is that the aircraft which is next to use the runway is always at the bottom of the bay, or at least, below any other strip.
EFS, NZWN, been using E strips for a few years.

Kieran17

Thanks for the doc, so from a brief reading it seems in scenario one, Eurocontrol ITWP software will put the 'line up' above the 'landing'.
In scenario two, it could place the intermediate above or below depending on the time order of clearance issue, with a TOF/LUP warning if you get it backwards.

I only had quick scan through so my interpretation may well be off the mark...

alfaman

From what I've seen over the years, it depends...overall, though, the principle that the strip that represents the obstructing aircraft is oriented so that it impedes the one it is obstructing, seems to be fairly universal. If you keep that in mind, then where the strips fit will depend on how the strip display reflects the airfield layout, which naturally, can be quite different.

UnableATC

Scenario one is easily avoided by not using conditional clearances relating to the runway, as is the recommended SOP in accordance with EAPPRI 3.0.

Scenario two is always first departure (intersection departure) above the second departure (full lenght). This is based off a conflict search-approach to strip boards. Nothing is in the way for the one above, while the precense of a strip above the full lenght departure indicates that there is something in the way of him departing. Airborne strips are placed above the runway bay in this scenario.

The same positioning is made with vehicles on the runway in the case of issuing line up and wait (vehicle strip above aircraft in runway bay).

Gonzo

1. Arrival strip placed at the bottom. Departure strip placed in runway bay but above runway designator. Will be move below runway designator when cleared for take-off. (EGLL, EFS).
2. Both strips placed in runway bay, with runway designator at the bottom, above that the intersection departure, above that the full-length departure. Again only moved below the runway designator when cleared for take off.

HershamBoys

You can also, using old-fashioned FPS in holders, place the strip in a 'cocked out' position in the bay to act as a memory jogger for the conflict. I seem to recall that some EFS displays offer the same facility.

HB

Kieran17

Accepted, but if you like, we can modify the scenario a bit to say the landing aircraft has past the holding point, still on its landing roll when the departing aircraft is cleared to line up and wait. I take it from the second part of your response that in this case, the departing strip will be below the arrival (landed) strip...

In my location, I'm working combined procedural approach and Tower/Ground. The airspace isn't particularly big, only 31NM and up to 5500ft. In our runway bay in scenario one the departure will be below the arrival. Scenario two, the mid length above the full length. The reasoning behind this method is that it maintains the mechanics that are used in the active (airborne) bay with departures moving from the ground, up through the bay to get to the sky at the top and the arrivals are moving down through the bay to get to the ground. Scenario one, by having the departure below the arrival, it places a strip between the departing strip and the sky, blocking its progress up. Scenario two, the mid length is at the top, because it's closer to the sky than the full length (the mid length strip blocks the the full length strip from moving up the board).

This method is in contrast to the alternative of having the 'next to use' the runway at the bottom. So a departure strip has to move down the runway bay before it can go up through the board.

What I'd eventually like to know, and is the reason for starting this thread, is how far back in history it was when there was only one method of doing it, and what was the catalyst for the split into two methods. Obviously both methods work fine, and they both have their logical reasoning behind them. Has the two methods just always been the way it is, or is the divergence in response to a change in situational awareness methodology, ie paper strips as primary information moving to screen based situational awareness with strips for record keeping moving to screen based with integrated EFS? Does it stem from locations running airspace/approach and tower combined?


Indeed, it depends is right, but for some, the strip below is seen as the one obstructing, for others it's the strip above, and I'd like to know why...

On that note, does anyone know of particular ICAO docs or similar that provide guidance on the topic? I've been looking but haven't found the answers I'm after yet.



Thanks for the inputs so far
Kieran

alfaman

Ok, so I'm stretching back into the memory archives, but I think it relates to how the runway bay is used: going to be difficult to explain in words, but for some, the top of the bay is the close threshold, the bottom, the far threshold, such that an aircraft departing comes in at the top, &, when cleared for take off, is slid down the bay, until airborne, whereupon it leave the bay upwards. For others, it works in reverse; the strip is slid up the bay as the aircraft takes off. So the blocker goes in below or above, depending on how it's going to be "in the way" of that first departure.

jmmoric

As most of the above.

The aircraft that has the runway is at the bottom, anything told to land after or line up behind we put on top in the runway bay.

Works the same way with the traffic circuit, first aircraft we always have on the bottom, 2, 3 and 4 on top, so we have the sequence directly visible, and only have to move them below into the runway bay when giving a landing clearance.

Same thing when vectoring doing approach work, once the sequence is figured out, strips are arranged accordingly, first at the bottom.

Though when working procedurally..... according to level, so we always have the next "conflict" apparent on the board when climbing/descending.

And when we do everything from one position...... a bit of everything.... procedural work on the top, radar work below, and pattern lowest.... Runway bay is the same.

TCAS FAN

Brings back one of the lighter moments of a past life. Was on an OJTI seminar and listening to a human factors presentation given rather petite pretty Asian girl (could say that before the PC brigade arrived) who was highlighting the use of “cock out, cock in, cock out”. Myself and a colleague were almost wetting ourselves trying to keep a straight face!

Glamdring

That sounds like an accident waiting to happen. Is this actually taught somewhere in the UK?

2 sheds

As regards a UK ITO - No, it is not. The display needs to reflect what has has been permitted to occur, even if this is a conditional instruction and even if a stop-bar will need to be cancelled.

2 s

Glamdring

In which case I'd really like to know where cliched86 works so that I can avoid ever being on an aircraft there :P

2 sheds

I blame the unit management and the CAA. You might think that this critical part of the data display, vital in every traffic situation from busy VFR to LVO, would be specified precisely in all MATS 2 (it is in some) and the significant elements be common to all units?

A few years ago, I conducted a straw poll on this subject with former colleagues at several regional airport ATCUs (not NATS, who have got their act together). The responses varied from one method to the complete opposite, from specified in MATS 2 to nothing specified, plus a sprinkling of personal preferences and variations and “we were always taught to do it like this” and “personally, I always do it like this.”

A frequent factor seemed to be lack of clarity about what information needed to be displayed and the most logical way of displaying it, plus a frequent confusion with what might be described as a procedural approach control format. I related this to a CAA Inspector and suggested that was a subject that warranted regulation, including the fact that at the time, ITOs were advocating different methods. Allegedly the subject was going to be raised at some forum, but the net result was an apathetic zero.

I would suggest that a basic principle ought to be that the data display, whether EFPS, manual strips or pinboard, reflects the reality of the relative positions of aircraft and vehicles as seen directly from the control room as well as on any ATM and SMR, plus any significant clearances that have been issued, e.g. landing, take-off, line-up only, conditional crossing, number three to follow…, holding visually etc. Having said that, if we were to start with a clean sheet and cleared our minds of any preconceptions, there is no reason with a strip display why all the strips could not progress up the board, I.e. as if the “pilot’s eye” view of events.

2 s

Kieran17

​​​​​​
Thanks for your input into the topic, are you able to expand on what you mean by having all strips moving up? Is this including arriving acft as well? How would the mechanics of a 'pilot eye view' system work?

Thanks
Kieran

2 sheds

Hi Kieran
I was only emphasising that we have this hang-up of essentially the strips moving down the display - but for what reason? Has an alternative ever been considered? After all, in most cases, we are probably looking at a runway situation where the traffic is essentially moving left to right or right to left in our vision but representing it with a vertically aligned display.
I should hope that the aircraft themselves are going in the same direction on final approach and immediately after departure! - so yes!
I am not suggesting it, but what I meant was...

First airborne
Second airborne
RUNWAY END
Aircraft/vehicle(s) occupying runway
RUNWAY THRESHOLD
No 1 inbound
No 2 inbound

2 s

jmmoric

I've seen examples where several bays are used, so there's a bay for aircraft taxiing in and out, one for the runway and circuit and one for inbound and outbound IFR flights....

But I think it's one of those things a unit can more or less decide/describe themselves. Some units do not have it written at all and allow for some freedom among controllers to decide themselves, myself due to being tall have to push everything a bit further up the bay or else I sprain my neck looking at the bottom of the bay.