OBJECTIVES:

• To explain the differences between DEP, ARR and APP
• To learn how to work as an approach controller

APPROACH CONTROL, THAT IS ARRIVAL + DEPARTURE CONTROL

Tasks

Appoach Control, that is Departure and Arrival Control, handles all IFR traffic in the Terminal Control Area (TMA). That is all arriving and departing IFR aircraft in the vicinity of one airfield or of several airfields which are close to each other. Local rules may differ!

Note: Departure Control handles the departing traffic, while Arrival is responsible for the arriving traffic. On the more busy airfields these fucntions could be seperated. On the smaller airfields, normally these are combined. Only when they are combined, the position is called Approach.
In the ACADEMY we will use the terms approach (APP), departure (DEP) and arrival (ARR) as convenient. When it reads APP it means the general approach and therefore will normally apply to DEP and ARR separately as well. Otherwise there will be a specific use of the individual terms.

General

The approach controller (APP) will guide the traffic through the Terminal Control Area (TMA). Departing aircraft are released by TWR immediately after their departure and DEP/APP will be responsible until the aircraft reaches the SID (Standard Instrument Departure) point or any other position, as agreed, where that traffic is released to the next unit. That next unit normally will be the Area Controller (ACC, in VATSIM CTR).

The same applies the other way around. Area Control will release the aircraft in time at or before the release point, normally the Initial Approach Fix (IAF), so that ARR/APP can guide them towards the landing runway.

If there is separately a Departure and Arrival Controller, the tasks of APP are divided and there will be no APP as such. The DEP will handle all departures and ARR will take care of the arrivals.

Note: Local differences may appear where additional or different agreements exist.

The job

To work as an ARR or DEP (APP) controller it is important to know the different Standard Instrument Departure (SID) routes and the appropriate arrival procedures, including the ILS and/or VOR/DME and sometimes NDB approaches. Depending on the weather and on the equipment of the aircraft, IFR traffic will not always perform a full ILS appraoch, but it may be vectored by APP/ARR to a point in front of the runway where it could easily intercept the ILS.
In addition, there are many airfields around the world that have no ILS at all. They will use the installed VOR/DME and/or NDB for the published VOR/DME or NDB approach.

Another very important and often difficult task is the so-called sequencing. Aircraft performing arrival procedures still need to be properly separated from each other and in the end only one could land at the time. So the distance on final approach between landing aircraft should be as such that the first landing aircraft has vacated the active runway before the next landing one can receive a landing clearance.
If you put them too close, it may mean that the second one has to go around and has to be put back into the queue. Quite often not so easy, because you had already a proper sequencing, which then has to re-arranged again.

In other words, a lot of special tasks for approach controllers.

A very important tool is speed control. Aircraft in appoach will gradually slow down towards the final landing speed. By allocating from the beginning allocated speed to the traffic, you can control the distance in between them much easier. Another advantage of slow speed is that their turns will be much shorter and easier. You could use this to let them turn either for separation but as well for gaining or losing distance between them.

All in all specific techniques typical for an appraoch controller.

In ATC the general rule of "first comes, first served" is valid. However, there are different factors that could influence this. e.g. It is easier for separation to have a fast aircraft fly in front.
At the other hand, a slower or lighter aircraft may turn much easier and earlier and therefore sometimes could be more easily "squeezed" into the traffic sequence. And smaller aircraft not always need the full length of the runway.
Quite often bigger airfields have more than runway and use different runways for different types of traffic. Turbo-props quite often use the shorter, different runways compared to the jets.

CLEARANCES

APP (DEP+ARR) is responsible for the usual clearances in his area of his responsibility.
For departures that is from the runway climbing towards the SID point.
For arrivals this will be normally the clearance to perform the selected approach (ILS, VOR/DME, NDB, etc), hereby clearly specifying for which runway!!

Note: When descending through the Transition Level, always give the local QNH

When the traffic is established on final, then hand it off timely to the next unit (TWR), since TWR is responsible for the separation on final and for the landing clearance.

In VATSIM,
if there is no TWR (and GND) available, APP takes over the tasks of those units.

TRANSFER or HANDOFF

• For departures, the transfer to ACC (CTR) is done well before the aircraft approaches the agreed hand-over point or position, normally the SID point.

• For arrivals, the transfer will be done from ACC (CTR) well before the aircraft reaches the agreed entry point into the TMA, normally the IAF.

ATIS

The APP/ARR/DEP controller has to make an ATIS which should carry the same basic information of that shown by the other ATC units for the same airfield. Always check this!!

Be advised that TWR determines the landing and departure runway(s).

For information in how to fill in the ATIS, see the Chapter about "ATIS".

At work

To start working as an APP controller, you need to have some basic information available.

• Connect and log-in:
  See the chapter about "Connection Instructions"

• Identifier:
  The name of your position to correctly log in
  See the chapter about "Identifiers"

• Frequency:
  The correct radio frequency of your position to be selected in the Comms Panel

• Coordination:
  Advise your neighbouring positions ( TWR or ACC/CTR) that you are there and ready
  See the chapter about "Coordinations"

• Phraseology:
  Know what to say, how to say it and when to say it..
  Study carefully the chapter about "Phraseology"

If APP is not on line?

Within VATSIM, there is the following rule:
ATC will preferable take the highest available position in line with his rank and the existing FRA's.

Note: FRA stands for Facility Rating Assignment, which means that there may be limitations for manning a certain ATC position. If you don't meet these requirements, you cannot take that position.

This rule is based on the fact that within VATSIM each ATC position controls at all the lower positions, if those are not occupied.
e.g. if only TWR is active, he will provide, additionally to his own TWR control service, all the services of DEL and GND.
Similarly, the Area Controller (ACC, but in VATSIM CTR) will provide additionally all airfield services in his region, if these are not manned.
That includes APP, TWR, GND and DEL for all airports in his area!

Note: When you log-in at an airport, make sure that you have checked which is the lowest available position.

In practise, quite often, it will be hardly possible for the CTR controller to do all these positions by one person. Therefore, they may leave the responsability of start-up, push back and taxi to the discretion of the pilots. The phraseology then used sounds like: "Start up and push back at your discretion". "Taxi at your discretion holding point xx runway yy, qnh **** " ....... etc.
It is obvious that the pilots should have a sharp look out themselves now to avoid any conflicting traffic situation and apply all the rules as it should be.
In addition, play it fair and don't start racing to be number one at the holding.

For details in the case there is no ATC at all available at the airfield or area you have planned to fly, look up the Chapter about "UNICOM"