This is a series of tutorials and practical flying exercises prepared by the CIX VFR Club to introduce members to online ATC and to enable them to learn at their own pace how to use it. Each lesson consists of a Groundschool section on aviation law and theory, and a Practical exercise to fly using the information in the Groundschool.
There are three basic types of Air Traffic Control with which Club members flying under Visual Flight Rules (VFR) will need to know about.
- Air Traffic Control (ATC).
- Aerodrome Flight Information Service (AFIS).
- Air/Ground radio (A/G).
The difference between them is all to do with the level of information or instruction given to pilots.
For a long time VATSIM had almost no ATC services other than full ATC, but from time to time A/G and AFIS services are coming on line as pilots recognise the fun to be had flying small aeroplanes around little aerodromes. Therefore all types of service are covered in this series of lessons.
This lesson describes procedures at Airports - those larger aerodromes which have a mix of light aircraft and commercial passenger and cargo traffic. Invariably, Airports have a full ATC service and may also (but not necessarily) have a large area of controlled airspace surrounding them, such as Heathrow, Manchester or Liverpool.
Read Chapter 3 of the Club's Air Traffic Control Manual for VFR Pilots which is on the web site in the Training section, Tutorials subsection.
To download the file, click on the 'Radiotelephony Manual' link under 'VATSIM'. In addition you may wish to obtain a copy of the CAA official publication, CAP 413 'The Radiotelephony Manual' which contains every official ATC instruction and response. (CAP by the way stands for Civil Aviation Publication'). This is available to download completely free from CAP 413 However, don't be frightened off by the huge amount of information it contains. You will be guided in these tutorials in the important parts needed. Possibly as little as a quarter of the total contents are applicable to Flight Sim and VATSIM.
At Airports, Air Traffic Control services are often divided into two or three types: -
- Ground - Controls aircraft startup and parking and movement along taxiways up to the hold for the active runway.
- Tower - Controls aircraft moving onto and off the runway, take off and landing, and within 2 to 3 miles of the Airport outbound and inbound..
- Approach - Controls aircraft departing the Airport from 2 to 3 miles from the Airport until they contact their next en route Air Traffic Service Unit (ATSU) or, inbound they 'receive' the aircraft at 10 to 15 miles out and control its movement towards the final approach path.
The smaller regional airports do not have a separate Ground Movement Controller, as this duty is handled by the Tower Controller. At quiet times at some smaller Airports, Tower and Approach may be combined also. On VATSIM, it is rare to have all three positions manned, but Tower and Approach will be encountered at places like Heathrow, Gatwick and Manchester on many occasions.
VATSIM controllers have to sit exams in order to be able to control, and passing the lowest level exam entitles members to control Ground and Tower, but not Approach. Further exams are necessary for members to be allowed to operate with the much more complex Approach procedures. Even so, controllers are not 'let loose' at an Airport, but are 'Mentored' - receiving help and advice on a one to one basis via the VATSIM Teamspeak system.
More advanced still are the Area Controllers whose principal job is to manage the inbound and outbound intercontinental traffic. However, they can, and often do, offer Approach, and Tower services to aerodromes within their area of control. For example, Solent Radar covers Southampton and Bournemouth; Essex Radar covers Stansted and Luton, Cambridge and Norwich and a few others; Thames Radar covers London City, Biggin Hill, Manston and others. This is known as the “top down” rule in VATSIM, and is not the same as real world practice where every position is separately manned.
If you are a new pilot, be aware that any controllers you are working are unlikely to be as inexperienced as you. Obey their instructions, and ask for help if you are unsure of what to do. Read the Club 'Code of Conduct' document accessed from the Membership page of the web site. It contains a lot of useful advice.
It has to be said that to fly as realistically as possible, you are recommended to obtain real world aviation charts. They are normally updated annually, and real world pilots are required by law to fly with the current one. So if you visit your local flying club or flight school in April or May each year, when the new ones are published, you can usually obtain copies of the previous year's charts, which are perfectly good enough for flight simulator activities.
They are drawn at 1 to 500,000 scale and are commonly known as 'the half mill charts'. There are three which cover the whole of the UK; Northern Scotland, Northern England and Scotland from Liverpool to Glasgow, and Southern England from the Channel Islands to Liverpool. They are crammed with information, and if you were so inclined, you could spend a wet weekend doing little other than study them. Crucially, they show all the controlled airspace which you need to know about.
Only those aspects of controlled airspace which impact on VFR flight will be discussed here. For a full description of controlled airspace and how it all works, you will find further information in the Club Training Manual Exercise 16. The best source, if you can get hold of one, is a real world Flight Training Manual. It is sufficient to say that no aircraft, however big or important may enter controlled airspace without the permission of the relevant Air Traffic Service Unit (ATSU).
Most Airports in the UK have up to three types of controlled airspace around them. The smallest area is the Control Zone (CTR) which extends outwards typically 10 to 15 miles from the field and vertically from the surface to a height which varies from Airport to Airport. The CTR is there to protect passenger aircraft taking off and landing. Gatwick's CTR extends upwards to 2500 feet, Manchester's to 3500 feet and Newcastle's to Flight Level 109. For a full explanation of Flight Levels, read Exercise 16 of the Club's Flight Training Manual, available on the website.
Outside the CTR, often above it and also around it is the Control Area (CTA). The CTA is used to protect aircraft shortly before establishing on final approach, and after takeoff before they join the airways system.
Control Zones and Control Areas are usually Class D airspace. This means that light aircraft are permitted to fly in these zones under Visual Flight Rules (VFR) with ATC permission and under ATC control but will normally be subject to height restrictions to maintain separation from Intrument Flight Rules (IFR) flights - principally commercial aircraft.
Finally the busiest Airports, London Heathrow and Gatwick, and Manchester, have a Terminal Manoeuvring Area (TMA). The only thing you need to know about TMAs is that they are Class A airspace and as a VFR pilot in a light aircraft, you will never be allowed to go there. The London TMA covers most of the Home Counties and starts as low as 2500 feet and protects Heathrow of course, one of the busiest Airports in the world.
The real world rules about controlled airspace are applied by VATSIM controllers, so you need to be aware of where they are and what to do before you start flying around in them.
In the dialogue examples below, the pilot's dialogue is in blue type; the controller's in red. Words in brackets are optional.
After start up and before taxiing, the pilot should obtain (and write down) the 'Automated Terminal Information Service' (ATIS) broadcast where provided, particularly noting the designation letter (information Juliet in the example below). The frequency is given in the usual flight guides or on the CAA's AIS Aerodrome charts.
For FS and VATSIM, this procedure is slightly different. The details of how ATIS is managed on VATSIM is covered in detail in Lesson 1.
With ATC, your ground movements are controlled, so you must request permission to taxi.
Liverpool Ground (Tower): Golf Bravo November Oscar Zulu: Request radio check on wun two two daycimal niner zero and taxi [instructions] with information Juliet
Golf Bravo November Oscar Zulu Liverpool Ground: Reading you strength 5: Taxi to holding point Alpha One. QNH wun zero wun two.
Under ATC control, you must read back all instructions, so: -
Taxi Holding point Alpha One, QNH 1012: Golf Bravo November Oscar Zulu.
As you taxi along taxiway Alpha to holding point Alpha 1, you will be handed over to Tower, if Ground and Tower are separate (they often are at Liverpool).
Golf Bravo November Oscar Zulu Contact Liverpool Tower on wun two six daycimal tree fife.
Contact Liverpool Tower wun two six daycimal tree fife: Golf Bravo November Oscar Zulu
(Note the way numbers are pronounced. (See CAP413 Chapter 2 Section 1.4 for details). This doesn't always happen on Vatsim, so don't get hung up about it!).
Now You change frequency to Tower (you do have the Tower frequency preset in the standby window of your COMM 1 radio, don't you?). Your initial call to Tower is then: -
Liverpool Tower Golf Bravo November Oscar Zulu (approaching Alpha 1).
As mentioned in lesson 3, but worth repeating, note that the callsign used has been abbreviated part way through the dialogue. Officially, in the real world, and therefore on VATSIM, the pilot must not abbreviate his callsign until the controller has done so first, but to be honest, this rule is not enforced rigorously and you will hear a number of variations. Where is does matter is where there are two aircraft with similar callsigns working the same frequency, e.g. G-ACIX and G-BCIX, two Club aircraft. Then the controller will invariably ask both aircraft to always use their full callsign.
Tower will now issue you a clearance. It may be given while you are taxiing or while you are at the hold waiting for permission to enter the runway. It will help you if you can anticipate what the clearance will be. Try and find out what the procedures are for any airport you plan to use well before your flight. At Liverpool, for example, VFR traffic is always routed out of or into the control zone at one of four points:
- Chester - for southbound traffic off runway 27 or inbound to runway 09 from the south
- Oulton Park - for southbound traffic off runway 09 or inbound to runway 27 from the south
- Seaforth - for northbound traffic off 27 or inbound to runway 09 from the north
- Kirkby - for northbound traffic off 09 or inbound to runway 27 from the north
If you look at the half million chart around Liverpool, you will see the Visual Reference Points (VRPs) marked with small black crosses in a black circle on a white background with an identifying label beside them.
Airports which have mixed light and heavy traffic have to separate them safely. This is done by keeping light aircraft at heights of 1500 feet above aerodrome level (aal) or below, and heavy aircraft at 2500 feet or above. The separation of 1000 feet vertically is the standard safe separation used for passenger and other large aircraft.
So: You now know what your clearance will be as you line up at Alpha 1 for a departure to Gloucester from runway 27, and it is no surprise when Tower suddenly says to you:
Golf Oscar Zulu you are cleared to leave the zone at Chester, VFR, not above wun tousand fife hundred feet QNH wun zero zero tree
It's those numbers again, not spelling mistakes - and note that he didn't say 'fifteen hundred feet'. That is considered to be insufficiently clear.
Now because this is an ATC instruction, you must read it back exactly. This is where anticipating what it will be helps enormously as you can rehearse it in advance.
Cleared to leave the zone at Chester, VFR, not above wun tousand fife hundred feet, QNH wun zero zero tree: Golf Oscar Zulu
Note very carefully that this “clearance” is not a clearance to take off. It is a clearance to enter controlled airspace after take off. Clearance to take off comes later (see below). Because this is in effect formal permission to enter controlled airspace, ATC will acknowledge that you have received the clearance correctly.
Golf Oscar Zulu read back correct
Which should give you a warm glow of satisfaction. Note that at smaller airfields without any controlled airspace around them except an ATZ, clearnces of this nature are not required or given, although you may be asked to report passing a Visual Reference Point (VRP) or significant landmark, so that the controller can delete your aircraft from his system.
Engine run up and vital actions are completed at the holding point. When these checks are complete, you are ready for your next instruction, so you say.
Golf Oscar Zulu at Alpha 1 Ready for Departure
Note that it is not 'Ready for take off'
What ATC says next can vary depending on circumstances, but will eventually include the words:
cleared for take off runway 27
Now that is your clearance to take off. Until you hear those exact words, you do not have permission to take off. Here are a few examples of what you might hear.
Golf Oscar Zulu line up and wait runway 27, number two for departure
Golf Oscar Zulu hold position. 2 minutes delay for wake vortex separation
Golf Oscar Zulu, Runway 27, with a left turn out, cleared for take off
Golf Oscar Zulu are you ready for an immediate take off?
Only one of those is a take off clearance. Of course you know which one.
Of course you are turning left for Chester, but by adding with a left turn out Tower is just reinforcing that he doesn't want you turning right and circling over the runway. Remember from Lesson 3 that It is illegal to take off until given an instruction which includes the exact words 'cleared for take off' (the runway number will vary of course). You MUST NOT take off until you have had that instruction, and you MUST read back at least the words 'Cleared for Take Off' and your callsign.
Cleared for take off runway 27 Oscar Zulu
If you do get an interim instruction before being cleared for takeoff, such as: -
Golf Oscar Zulu line up and wait runway 27
You obey the instruction and you read it back.
Line up and wait runway 27, Golf Oscar Zulu
Remember all ATC instructions must be read back. In the particular case of line up and wait you do not say anything at all once you are lined up. ATC knows you are there - he can see you. Occasionally ATCOs do forget you, so after an interval of perhaps 2 minutes, you can remind him. That is quite in order (he's only human).
Golf Oscar zulu is holding on runway 27
The instructions to inbound aircraft will be given by the Approach controller. Pilots contact Approach 10 miles or 5 minutes (whichever is the greater) before reaching the boundary of the Airport's controlled airspace. The pilot must request permission to enter the controlled airspace. His initial call is the normal formal 'Hello I'm here': -
Liverpool approach, Golf Bravo November Oscar Zulu
Liverpool will reply: -
Golf Bravo November Oscar Zulu, pass your message.
The pilot then makes a slightly abbreviated CEPHACER report.
Liverpool approach, Golf Bravo November Oscar Zulu, Cessna 152 inbound to Liverpool from Gloucester. Passing Wrexham. Request entry into the zone at Oulton Park.
Liverpool will reply: -
Golf Oscar Zulu, enter the zone at Oulton Park not above wun tousand fife hundred feet. Liverpool QNH 1012. Report at Oulton Park.
Permission to enter the zone is granted. Remember that you must read back that, and all, instructions given you. Approach will normally ask you to report entering the zone, but they may not, because they can see you on radar. However, you should report entering the zone anyway.
Liverpool approach, Golf Oscar Zulu passing (or overhead) Oulton Park.
Liverpool will then give a further reporting point and ask you to report when you have the field in sight. The two are often combined
Golf Oscar Zulu, you are cleared to Helsby. Report the field in sight.
This means that you must not proceed beyond the hill at Helsby on the south bank of the Mersey south east of the airport. Of course you know where that is - well you do after you've made the same flight several times. Such local knowledge is very valuable, so it's a good idea to make a number of flights into the same airfield and gain that local knowledge. In this way subsequent flights become more fun and less stressful for new pilots.
Read the instruction back and then when you see the Airport, simply call: -
Liverpool approach, Golf Oscar Zulu field in sight.
This is Approaches cue, if they haven't done so already to hand you over to Tower.
Golf Oscar Zulu contact Liverpool Tower wun two six daycimal tree fife.
Read that back, and call tower with a very simple 'hello' call. They know you are coming!: -
Liverpool Tower, Golf November Oscar Zulu (approaching Helsby).
Golf Oscar Zulu join left base runway 27. You are number two to a 737 on an eight mile final.
Join left base runway 27, number two. (I have the traffic in sight)Golf Oscar Zulu.
An old aviation joke is that the biggest lie in aviation is 'I have the field in sight', because very often in the real world, you can be very close to an airfield, know that you should be able to see it, but can't, so you bluff in the hope that you will see it before it's too late! On VATSIM, you can see runway approach lights from a long way away and also other aircraft's red ID tag in the sky if they are within 10 miles of your position, so there should be no need to lie!.
In the real world, Tower will see you out of the window, but on VATSIM, although there is now a Tower facility, many controllers still watch their radar screen to see when you join base leg. By the way, you will never be asked to make an overhead join at a busy airport, and I can hear your sigh of relief from here!
Your next call is very brief: -
Golf Oscar Zulu left base
Golf Oscar Zulu report final.
Report final, Golf Oscar Zulu.
Then as you turn final: -
Golf Oscar Zulu final (27)
Remember, you MUST NOT land unless given the explicit instruction
Cleared to land
You may receive different instructions from the one you are expecting, so be prepared.
Golf Oscar Zulu take up a left hand orbit in your current position until advised
Golf Oscar Zulu Go around. I say again, go around.
Hopefully, you will receive:
Golf Oscar Zulu Cleared to land Runway two seven, Surface wind two six zero degrees zero eight knots.
Note that the ATCO gives you also the runway to land on, by way of confirmation - pilots frequently make approaches to the wrong runway - and the surface wind.
You MUST repeat back
Cleared to land (27) Golf Oscar Zulu
Note that you do not read back the wind, and reading back the runway is optional. If you do not receive a 'Cleared to land' instruction then you MUST initiate a missed approach and rejoin the circuit for another attempt. This is as true on VATSIM as it is in the real world which we are trying to emulate. Specific landing and take off clearances are only required at aerodromes with full a ATC service. The airports manned on VATSIM are full ATC airfields, mostly.
After landing you will be asked to leave the runway at one of the taxiways and taxi to parking. General Aviation parking at Liverpool is on a separate apron on the other side of hold Kilo.
Golf Oscar Zulu exit at Foxtrot and taxi via Alpha to Kilo.
Read it back, and do as the man says.
Of course you need to find out where foxtrot, alpha and kilo are, so you need the airport diagram from the NATS web site, Aerodromes published in the UK AIP
or a copy of one of the popular flight guides, e.g. Pooleys. I bought my first Pooleys in 1991 purely for Flight Simulator and 3 years before I learned to fly for real. It's a fascinating book and contains almost everything you need to know about VFR flight, so you might choose to do the same. Like charts, it is republished every year, so you might be able to get hold of an old one.
Shut down and go and have a drink. If it is your first such flight, you will be shattered! But you will feel a sense of achievement. The next one will be easier, and the next one easier still.
Of course on VATSIM, you may not have both approach and tower, so the instructions will differ slightly. If only tower is on duty, he cannot give you approach instructions, so you when you make your initial call inbound he will ask you to report the field in sight, as that is the boundary of his jurisdiction. You should still enter the zone at one of the reporting points - that's good airmanship.
If only approach is on duty, then he will give you zone entry instructions and will control you right down to landing and parking.
There are many more possible instructions, all listed in CAP413. Learn as many as you can which are applicable to CIX VFR Club flights, and practice them almost anyway you like. The Club offers one to one ATC voice practice, which can be a good starting point.
Once again, it is worth simply listening to the dialogue used with different air traffic control systems. Position an aircraft at Liverpool (Liverpool is frequently manned on a Monday evening) and log into VATSIM. There should be traffic using the airport, inbounds, outbounds, commercial jets and private light aircraft, plus circuit traffic. Simply sit and listen to the dialogue between the ATCO and the aircraft.
You can repeat the practical in Lesson 1 if you wish for additional practice, and add a little helpful information at the same time.
Liverpool Tower, Golf Bravo November Oscar Zulu request radio check
If all your software installation and VATSIM connection process has worked, ATC should come back to you with
Golf Bravo November Oscar Zulu, Liverpool Tower receiving you strength 5, how me?
And you reply:
Liverpool Tower, Golf Bravo November Oscar Zulu receiving you strength 5 also, thank you. We are carrying out ground training and will not be flying.