Difference between revisions of "Study Guide"

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(LOWL (Blue Danube Airport))
Line 680: Line 680:
==== Pisten ====
* '''10/28:''' Beton mit 2720 Meter (8294') Länge und 45 Meter Breite
* '''10R/28L''' Graspiste mit 710 Meter (2329') Länge
Folgende Anflugverfahren stehen für Klsgenfurt zur Verfügung für die Piste 10/28:
* '''ILS'''
**28: 110.10 (OEK) 285°
* '''NDB'''
**10: 405 (KW) 105°
==== ATC-Stationen in Klagenfurt ====
* LOWK_TWR (Klagenfurt Tower) auf 118.100
* LOWK_APP (Klagenfurt Radar) auf 126.820

Revision as of 09:14, 8 May 2008

Diese Seite dient der Entwicklung der Trainingsdokumente der FIR Wien.


Study Guide: Tower


This Study Guide has been designed to give you all the information needed to start controlling as a Tower controller on the VATSIM network.

Radio Communication - Basics

Because Communication is crucially important for Air Traffic Control a fixed format and syntax us used, in order to minimize the risk of misunderstandings and to keep messages short. Worldwide English is the primary language in use, however in most countries you are also allowed to use the local language. In Austria VFR flights can choose their language whereas IFR flights are mostly conducted in English. Link: Buchstabiertabelle

Basic Rules

In order to achieve the goals set above the following rules important:

  1. Listen before you talk
    It's impossible for two radio stations to transmit on the same frequency at the same time. If this is done, the radio signal will be blocked and this will result in a nasty noise on the frequency. Therefore it's important that every station monitors the frequency for about 5 seconds before transmitting, to make sure there’s no ongoing radio traffic. If you hear an ongoing conversation, wait until the conversation is over before you begin to transmit. Don’t start your communication if there is a read-back expected on the last transmission even if there is a short pause.
  2. Think before you talk
    The radio traffic flow should be as smooth as possible. To achieve this it's vital to "think first" before transmitting so that a clear, concise and uninterrupted message can be sent.
  3. As far as possible use standard phraseology and syntax
    To prevent misunderstandings and to maintain the radio traffic as effective as possible, stick to standardized phraseology and skip slang and of course private messages.

Callsigns and Initial Contact

Every participant on the network has his own Callsign. Controller Positions are identified by their location and their Function (e.g. Wien Radar, Graz Tower), Aircraft either by their Registration (e.g. OE-ALB) or an Airline Callsign followed by a combination of numbers and letters (e.g. AUA25LM, SWR387). To pronounce these letters and digits the ICAO-Alphabet is used. To initiate the contact between two stations an initial call has to be made. This call has the following structure:

Station 1: Station 2, Station 1, Message 
Station 2: Station 1, Station 2, Message

Example - Austrian 251 is calling Wien Tower:

AUA251: Wien Tower, Austrian 251, established ILS 34 
LOWW_TWR: Austrian 251, Wien Tower, continue approach

In Subsequent calls the calling station part can be ommited.
When a controller (or aircraft) transmits a message to a station it is very important that the receiving station acknowledge the message and reads back any required parts.. If the receiving station does not acknowledge, the transmitted message is considered as a lost transmission and the sender should resend the message or check if the receiving station got the message. Items that must always be read back in full are all clearances (including altitudes, heaings, speeds, radials etc), runway in use, altimeter setting (QNH or QFE) and transition level, and all frequencies. For a controller, this is extremely important to remember, since if a pilot's readback is incorrect, the controller has to ask for confirmation, i.e a new readback. There are also items that should not be read back to reduce unnesessary radio transmissions. In short, this includes everything not mentioned above, but a few examples are: wind, temperature and other weather information (except altimeter settings) and traffic information in detail. When giving an instruction the Callsign is stated at the beginning, when reading back you usually add it at the end of your transmission (although you are allowed to do it at the beginning too).


LOWW_APP: AUA251, turn left heading 290, descend to Altitude 5000 feet, QNH 1019.
AUA251: Turn left heading 290, descending to altitude 5000 feet QNH 1019, AUA251 

LOWW_GND: OE-DLT, taxi to Holding Point Runway 29 via Exit 12, M and A1, give way to Speedbird Airbus A320 crossing you right to left on M.
OE-DLT: Taxiing to H/P Rwy 29 via Exit 12, M and A1, giving way to Speedbird Airbus A320 on M, OE-DLT.

LOWW_TWR: NLY2678, wind 330 degrees at 6 knots, Rwy 29, cleared for takeoff.
NLY2678: Rwy 29, cleared for takeoff, NLY2678.

Aircraft and basic Flying Principles


References for detailed information: METAR, TAF

How is an Aerodrome Organized?

Der TWR (Flugplatzkontrollstelle) ist zuständig für den :

Personen und Fahrzeugverkehr auf Manövrierflächen

Nachdem Follow-Me Fahrzeuge nicht mehr eingesetzt werden dürfen entfällt hier der zweite Punkt.
Die Flugplatzkontrollstelle kann nun auch weiter untergliedert werden in die Positionen Delivery (DEL), Ground/Rollkontrolle (GND) sowie Tower/Turm (TWR).

Die nächst höher gelegene "Instanz" ist die APP (Anflugkontrollstelle)

Kontrollierte An- und Abflüge

Die Anflugkontrollstelle in Wien ist für An- und Abflüge zuständig und kann bei Bedarf sektorisiert werden. So kann man den LOWW_APP in jeweils einen Nord-Süd Sektor teilen, oder aber in einen Upper-Lower Sektor aufteilen. Zu Spitzenzeiten werden die Sektoren nach beiden Verfahren geteilt, noch dazu wird eine Director-Position eingerichtet, die LFZ vom Lower Approach auf das ILS führen.

Darüber befindet sich die ACC (CTR) Bezirkskontrollstelle

Für alle übrigen kontrollierten Flüge

Bei VATSIM bearbeitet der LOVV_CTR das gesamte Bundesgebiet und übernimmt auch die Tätigkeit des TWR & APP auf allen österreichischen Flughäfen, sollten diese nicht online sein. Das Gebiet Tirol & Vorarlberg über FL165 wird nicht von LOVV kontrolliert, sondern im Auftrag der ACG von der deutschen Flugsicherung mitbetreut (EDMM).
>br> Alle drei Kontrollstellen üben den Kontrolldienst gemäß §68 Abs.1 LVR aus und erfüllen folgende Aufgaben:

Sicherheit gewährleisten durch
 Vermeidung von Zusammenstößen zwischen Luftfahrzeugen
 Vermeidung von Zusammenstößen zwischen Luftfahrzeugen und Hindernissen auf den Manövrierflächen
Wirtschaftlichkeit gewährleisten durch raschen, flüssigen und geordneten Ablauf des Verkehrs

Diese Aufgaben gelten auch für den Controller in VATSIM, wenn auch aus anderen Beweggründen. In dem Wunsch so nahe an die Realität wie möglich zu kommen, sind diese Leitfäden unerlässlich.

Working Delivery Positions

Clearence Delivery is responsible for checking and correcting flightplans of departing aircraft and issue routing clearances to them.

Flightplan Structure

Flight plans are documents filed by pilots with the local Civil Aviation Authority prior to departure. They generally include basic information such as departure and arrival points, estimated time en route, alternate airports in case of bad weather, type of flight (whether instrument flight rules or visual flight rules), pilot's name and number of people on board.
For IFR flights, flight plans are used by air traffic control to initiate tracking and routing services. For VFR flights, their only purpose is to provide needed information should search and rescue operations be required.

Routing Types
Aircraft routing types used in flight planning are: Airway, Navaid and Direct. A route may be composed of segments of different routing types.

Airway routing occurs along pre-defined pathways called Airways. Mostly aircraft are required to fly airways between the departure and destination airports. The rules cover altitude, airspeed, and requirements for entering and leaving the airway (SIDs and STARs).
Navaid routing occurs between Navaids (short for Navigational Aids) which are not always connected by airways. Navaid routing is typically only allowed in the continental U.S. If a flight plan specifies Navaid routing between two Navaids which are connected via an airway, the rules for that particular airway must be followed as if the aircraft was flying Airway routing between those two Navaids. Allowable altitudes are covered in Flight Levels.

Direct routing occurs when one or both of the route segment endpoints are at a latitude/longitude which is not located at a Navaid.

Issuing IFR Routing Clearances

DEL gives routing clearances to all departing aircraft with the following information:

Destination of aircraft
SID (= Standard instrument departure) Normally the filed SID is given
Initial climb altitude after departure (5000ft)
Squawk (Squawk assignments for LOWW are 4600 to 4620)
QNH (Local QNH of airport according to latest METAR)
CTOT (= Calculated take-off time) Slot time (Normally not used on the VATSIM network)

The bold marked points are mandatory, all other points are optional.

Normal construction of a routing clearence:

Callsign, cleared to XXXX via XXXXX XX departure, (climb initially 5000ft), Squawk 46XX, QNH XXXX


Austrian 125, cleared to Frankfurt via LUGIM 1C departure, climb initially 5000ft, Squawk 4601, QNH 1020.

After a correct read-back of the pilot hand-off him to next higher position (i.e. GND)

Special Situations (High Traffic, Slots, ...)

Um zügigen Verkehrsfluß bei starkem Verkehr aufrecht zu erhalten, gilt es dem ankommenden Verkehr höhere Priorität als dem abfliegenden Verkehr zu gewährleisten. Hier sollte vor allem die Vergabe von Slots oder die Errichtung von Abflugintervallen eine große Rolle spielen. Ein Slot ist ein gewisser Zeitraum in dem ein Pilot seinen Start-Up, Taxi und Abflug durchführen sollte. Ein Slot folgt also dem anderen. Abflugintervalle dienen dazu, eine relativ große Anzahl von Abflügen in einem gewissen Zeitraum zwischen zwei Wellen vieler ankommender Flüge abzufertigen. Um genug Freiraum für Abflüge zu haben, ist die Koordination mit den Approach Positionen unumgämglich.

Phraseologie in Situationen mit erhöhtem Verkehrsaufkommen

Piloten am Boden kann man mit Hinweisen auf die zu erwartende Verzögerung das Leben leicher machen:

Austrian 125, readback correct, expect startup in 10 minutes
Austrian 125, startup approved, expect departure in 10 minutes

Working Ground Positions

Ground is responsible for all movements of aircraft on ground, except the movements on the runway. Ground takes over responsibility for Delivery if he is not online.

Start-up clearence
Start-up clearence can be given if no other aircraft is taxiing behind the starting-up aircraft and if the take-off is expected in 20 minutes or less.

Austrian 125, start-up approved, (Temperature Minus 3)

Push-back clearence
Push-back clearence can be given if no other aircraft is passing behind and the parking position requires push-back (i.e. position at the gate, … [refer to charts])

Austrian 125, push-back approved”

Combination of both phrases
During low traffic you can use these two phrases together

Austrian 125, start(-up) and push(-back) approved

Taxi Instructions

The easiest way giving taxi instructions to aircraft is to:

Taxi outgoing aircraft on taxiway MIKE (former OSCAR) ASAP.
Taxi incoming aircraft on taxiway LIMA (former INDIA) ASAP.

In this way, collision of aircraft should be avoided. Incoming aircraft on runway 16/34 vacating via B3 to B10 should use taxiway DELTA and LIMA (former INDIA).

Ground Traffic Management

In case of a landing on runway 29 no aircraft is allowed to be in the extended runway centreline of runway 29 while landing aircraft is passing above. In this case aircraft should hold at ROMEO, FOXTROTT, SIERRA and GOLF and wait until the incoming aircraft touched down.
You can also advise aircraft to follow behind another aircraft or give way to other taxiing aircraft.

Austrian 125, follow Airbus 320 to holding-point runway 29
Austrian 125, give way to taxiing Airbus 320 passing from left to right

When an aircraft is approaching its assigned holding-point (and clear of possible traffic-conflict) a hand-off to next higher position (i.e. TWR) shall be initiated as soon as possible.

Austrian 125, contact Tower on 119.40

Intersection take-off
Intersection takeoffs can be granted by GND in coordination with TWR and in accordance or on pilot’s request.

Special Situations (High Traffic, Slots, ...)

Um zügigen Verkehrsfluß bei starkem Verkehr aufrecht zu erhalten, gilt es dem ankommenden Verkehr höhere Priorität als dem abfliegenden Verkehr zu gewährleisten. Hier sollte vor allem die Vergabe von Slots oder die Errichtung von Abflugintervallen eine große Rolle spielen. Ein Slot ist ein gewisser Zeitraum in dem ein Pilot seinen Start-Up, Taxi und Abflug durchführen sollte. Ein Slot folgt also dem anderen. Abflugintervalle dienen dazu, eine relativ große Anzahl von Abflügen in einem gewissen Zeitraum zwischen zwei Wellen vieler ankommender Flüge abzufertigen. Um genug Freiraum für Abflüge zu haben, ist die Koordination mit den Approach Positionen unumgämglich.

Phrasenzusätze in Situationen mit erhöhtem Verkehrsaufkommen

Um den Piloten eine Anweisung mit Nachdruck bekannt zu machen sollen folgende Phrasen angehängt werden. Dies ist vor allem bei der Runway Separation anzuwenden.

Austrian 125, ready for immediate departure?
Austrian 125, wind xxx/xx - runway 29 cleared for immediate takleoff

Traffic im Anflug kann man auch bitten die Runway rasch zu verlassen:

Austrian 125, wind xxx/xx runway 34 cleared to land, vacate as soon as practicable

Abfliegenden VFR Verkehr kann man darauf hinweisen den Abflugsektor rasch frei zu machen:

OE-ABC, wind xxx/xx runway 29 cleared for takeoff, after departure right turn as soon as practicable

Working Tower Positions

Tower is responsible for all movements on the runways as well as for all movements within the control zone (CTR), (10NM radius, GND to 2500ft MSL). Tower is also responsible for ground and delivery if they are not online. He also decides which runways are in use.


Bei der ATIS (Automatic Terminal Information Service) handelt es sich um eine automatisch generierte Informationsdurchsage für den Flugverkehr an größeren Flughäfen. Sie wird auf einer eigenen Frequenz in einer Endlosschleife gesendet und soll die aktiven Funkstationen am Flughafen entlasten. Piloten, die unter IFR an- oder abfliegen, sind verpflichtet, vor dem Erstkontakt mit der zuständigen Flugverkehrskontrollstelle zunächst das ATIS abzuhören. Beim Erstkontakt nennt der Pilot den ATIS-Kennbuchbuchstaben, um dem Controller zu bestätigen, dass er die aktuelle Version abgehört hat.

Bestandteile einer ATIS Meldung:

  • Name des Flughafens
  • Laufender ATIS-Kennbuchstabe
  • Zeit der Beobachtung des Flugplatzwetters
  • Aktive Landebahn
  • Übergangshöhe
  • Windrichtung und -geschwindigkeit
  • Flugsichten
  • besondere Wetterlagen (z.B. Regen)
  • Hauptwolkenuntergrenze
  • Temperatur und Taupunkt
  • QNH
  • Änderungstrend

Die ATIS wird alle 30 Minuten oder bei signifikanten Wetteränderungen erneuert.

Determination of active Runways

Pilots normally prefer to takeoff and land the aircraft with the nose into the wind because it shortens the Rwy length required to safely operate the aircraft. The wind direction given in the METAR is the direction the wind is coming from, so it is easy to compare this wind to your given runways.

You are the Tower controller at Salzburg Airport. The only runway at Salzburg is runway 16-34 so you have two directions available (roughly 160° and 340°.) The wind is coming from 180° at 5 knots. So the usual Runway in use would be rwy 16 for takeoff and landing.

However, at most airports a preferred runway configuration is defined (Find them here: Study Guide:Airport Details) which should be used if traffic situation and weather permits. Aircraft have certain limitations they can operate in, so normally the tailwind component should not exceed 5-10 knots (again depending on airport). Also the allowed crosswind is limited (This depends very much on the aircraft).
Be aware that it is the pilots responsibility to accept a certain wind component and that this decision is often based on performance issues, so one pilot might accept the next one refuses to take a certain runway.

So back to our example above:

At Salzburg, due to the terrain in the vicinity and city of Salzburg around the airport, runway 34 is preferred for departures and rwy 16 for landing. So the indicated configuration would be DEP 34, ARR 16.

Transition Altitude/Transition Level

Die Transition Altitude (TA) beträgt in Wien immer 5000 ft. Der Transition Level (TL) ergibt sich in Abhängigkeit zum aktuellen Luftdruck (QNH):

QNH      < 0977: TA + 3000 ft.
QNH 0978 - 1013: TA + 2000 ft.
QNH 1014 - 1050: TA + 1000 ft.
QNH 1051 >     : TA = TL

Zwischen der TA und dem TL befindet sich der Transition Layer, der einen Sicherheitsabstand von mindestens 1000 ft. zwischen dem "unteren Bereich" (Airport Elevation bis A5000 ft.) und dem "oberen Bereich" (Standard Luftdruck 1013 hPa bis Untergrenze TL) gewährleistet. Dadurch werden gefährliche Überschneidungen zwischen dem an- und abfliegenden Verkehr vermieden.

Runway Separation

The runways are one of the most dangerous spots on an airport because aircraft are travelling at high speed with little room to maneuver and most of the time no ability to stop at a reasonable distance. Because of this the general rule is that only one aircaft may be cleared to use a runway at the same time. What this means practically and exceptions from this rule are explained in the following chapters.

Departing Traffic

So now we are at the point where the pilot reaches the Holding Point of his departure runway and reports ready for departure. What are the things you should check before issuing the takeoff clearance?

  • Have a look at the flightplan. Take note of the type of aircraft and the Departure Route.
  • Check the traffic approaching the runway.

To give him the takeoff clearance the following phrase should be used:

 e.g.: TWR: AUA2CM, wind 320 degerees at 7 knots, Runway 29, cleared for takeoff.
 AUA2CM: Cleared for takeoff Runway 29, AUA2CM

The pilot lines up on the runway, advances the throttle and takes off. When he is well established in climb check he is squawking Mode C and the right Code. Afterwards he is handed off to the next Controller, in this case a radar position:

 TWR: AUA2CM, contact Wien Radar on frequency 128.20, bye bye!
 AUA2CM: Contacting Wien Radar on frequency 128.20, AUA2CM.

The next aircraft reports ready for departure. Again check the points above, but this time we cannot give the takeoff clearance straight away because the preceeding aircraft is still occupying the runway. Now you get to know the first exception to the Runway Seperation rule above. To speed things up you can instruct the next aircraft to line up behind the first one while this one is still in the takeoff roll occupying the runway:

 TWR: AZA639, behind departing Austrian Airbus A319, line-up rwy 29 behind and wait.
 AZA639: behind departing Airbus lining up runway 29 and waiting behind, AZA639.
 Note: The two times behind in this instruction is not a typing error but was implemented to emphasize that part of the clearance.

This type of clearance is called a conditional clearance.

The earliest possible point where you can issue the next takeoff clearance is, when the preceeding aircraft has overflown the opposite runway end or has clearly turned onto either side of it.
However in some cases this could be very close which leads us to the next chapter.

Departure Seperation - Based on Type of Aircraft and departure route

One of the main tasks of air traffic control is to keep aircraft at a safe distance to each other. So imagine the following situation:

  • Two aircraft are departing right after each other.
  • The first aircraft is a relatively slow Cessna 208 (~around 70 knots in climb), the second one a fast Boeing 767 (140-180 knots on the initial climb).
  • Both follow the same departure route.

Obviously it would not take long until the B767 catches up with the Cessna, a potentially very dangerous situation! You can see, that it is very important to check the flightplan of the aircraft you are about to clear for takeoff.
The minimum radar seperation in the area around an airport is 3 nm or 1000 feet. These are the limits radar stations have to obey. Tower Controllers should aim to achieve the following seperation for departing aircraft following departure routes which share a common part:

Fast followed by slow 3 nm
Matching Types 5 nm
Slow followed by fast 10 nm

In extreme examples like the one above it is often more advisable to coordinate with APP to find another solution. Often this involves clearing the aircraft to a non standard altitude or departure route:

 TWR: DLH2441, after departure maintain runway heading, climb initially to 3000 ft
 DLH2441: After departure maintaining runway heading, climbing to 3000 ft, DLH2441 
 TWR: DLH2441, wind 320 degrees at 9 knots, runway 29, cleared for takeoff
 DLH2441: Cleared for takeoff runway 29, DLH2441

The other main task of ATC is to expedite the flow of traffic. Situation:

  • You have numerous aircraft departing from the same runway, following different departure routes. Some of them involve immediate right turns other SIDs immediate left turns.
  • There are two holdingpoints available.

It would benificial to use the gaps that arise between the aircraft using similar Departure Routes, so in close coordination with ground you should try to distribute aircraft over the holding points in a way to be able to fill those gaps.

Departure Seperation - Based on Wake Turbulence Category

There are two ways aircraft influence the air around them when passing through it:

  • Jetwash produced by the engines
  • Turbulence created at the wings and especially at the wingtips

This turbulence can cause severe problems or even loss of control for following aircraft. The wake turbulence categories are based on the Maximum Takeoff weight (MTOW) of the aircraft:

Light Aircraft (L) < 7 000 kg
Medium Aircraft (M) 7 000 – 136 000 kg
Heavy Aircraft (H) >136 000 kg

For departing aircraft, 2 minutes separation (3 minutes if the succeeding aircraft departs from an intersection) is applied when an aircraft in wake turbulence category LIGHT or MEDIUM departs behind an aircraft in wake turbulence category HEAVY, or when a LIGHT category aircraft departs behind a MEDIUM category aircraft.
You may issue a take-off clearance to an aircraft that has waived wake turbulence separation, except, if it's a light or medium aircraft departing as follows:

  • Behind a heavy a/c and takeoff is started from an interception or along the runway in the direction of take-off.
  • Behind a heavy a/c that is taking off or making a low or missed approach in the opposite direction on the same runway.
  • Behind a heavy a/c that is making a low or missed approach in the same direction of the runway.

To point out this hazard to a pilot the following phrase should be used:

 TWR:ESK32C, behind departing heavy B777 line up runway 16 behind and wait, caution wake turbulence.
 ESK32C: behind departing B777 lining up rwy 29 and waiting, ESK32C.

Use of the word takeoff

The word take-off shall only be used in combination with the take-off clearence (cleared for take-off). For other phrases use the word departure (ready for departure – NOT ready for take-off!).

Arriving Traffic

  • Normal Landing Clearance
- LOWW_TWR: AUA123, wind ***/**knts, RWY **, cleared to land
- AUA123: Cleared to land RWY **, AUA123
  • Delayed Landing Clearance - Traffic ahead
- LOWW_TWR: AUA123, wind ***/** knts, RWY 34, continue approach
- AUA123: Continue approach, AUA123
  • Late Landing Clearance
- LOWW_TWR: AUA123, expect late landing clearance, [reason]
- AUA123: Roger, AUA123
  • Go Around
- LOWW_TWR: AUA123, go around, [reason]
- AUA123: Going around, AUA123
  • Handoff to Wien Ground
- LOWW_TWR: AUA123, contact Wien Ground frequency 121.600
- AUA123: Wien Ground frequency 121.600, AUA123

Merging Departing and Arriving Traffic

  • Wake Turbulence Separation
  • Seperation
- Heavy/Heavy: 4nm
- Heavy/Medium: 5nm
- Heavy/Light: 6nm
- Medium/Light: 5nm
  • Conditional Clearances
- LOWW_TWR: AUA123, Traffic short final RWY **, C750, report in sight
- AUA123: Traffic in sight, AUA123
- LOWW_TWR: AUA123, behding landing C750 line up RWY ** behdind and wait
- AUA123: Behding landing C750 lining up RWY ** behding and wait, AUA123

Merging IFR and VFR Traffic

  • Traffic Information
  • Visual Identification
- LOWW_TWR: OE-ANX, traffic at your 3 o´clock position, moving right to left, B767, distance 2.5 miles, report mentioned traffic in sight
- OE-ANX: Traffic in sight, OE-ANX
- LOWW_TWR: OE-ANX, behind B767 traffic, enter final RWY **, caution wake turbulence
- OE-ANX: Behind B767, enter final RWY ** behind, caution wake turbulence, OE-ANX

VFR Traffic - Differences

VFR traffic can enter/leave the control zone (CTR) via sector SIERRA (to the south), sector ECHO (to the east) and along the Danube river on the route Klosterneuburg – Freudenau. Maximum altitude in these sectors is 1500ft or according to the VFR charts published online at www.vacc-sag.org.

VFR flights should be guided into downwind, base and final leg for landing.

Used phrases:

OE-AGA, enter control zone via VFR route Klosterneuburg – Freudenau, 1500ft or below,
QNH 1020, Squawk 4604, report XXXX (i.e. Freudenau)
OE-AGA hold (orbit) overhead XXXX (i.e. Freudenau) in XXXX (i.e. 2500ft)
OE-AGA, enter downwind for runway 29, report on downwind
OE-AGA, enter base for runway 29, report on base

VFR Flights get their Clearance from Delivery . After startup, they will contact Tower for taxi. A possible VFR Clearance could be:

OE-AGA, verlassen Sie die Kontrollzone über Sichtflugstrecke Klosterneuburg, 1500 Fuß oder darunter,
QNH 1014, Squawk 4607, Rechtskurve nach dem Abheben so bald als möglich.
OE-AGA, leave controlzone via VFR-route Klosterneuburg, 1500 feet or below, QNH 1014, Squawk 4607,
right turn after departure as soon as possible.
OE-AGA, steigen sie auf 3500 Fuß, melden Sie Donauturm.
OE-AGA, climb 3500 feet, report Donauturm.

Note: Wien Tower/Turm can also be contacted in German.

Information Positions

  • Traffic Information
  • Weather Information
  • Special Requests

LOWW_I_APP (118.520) and LOVV_I_CTR (124.400) are the 2 FIS Positions within Austrian airspace. They are responsible for the VFR Flights. They allocate Squawks, provide Traffic Information and offer Weather Information (worldwide) and coordinate with other controllers requests from pilots.

Special Situations (High Traffic, Slots, ...)

Um zügigen Verkehrsfluß bei starkem Verkehr aufrecht zu erhalten, gilt es dem ankommenden Verkehr höhere Priorität als dem abfliegenden Verkehr zu gewährleisten. Hier sollte vor allem die Vergabe von Slots oder die Errichtung von Abflugintervallen eine große Rolle spielen. Ein Slot ist ein gewisser Zeitraum in dem ein Pilot seinen Start-Up, Taxi und Abflug durchführen sollte. Ein Slot folgt also dem anderen. Abflugintervalle dienen dazu, eine relativ große Anzahl von Abflügen in einem gewissen Zeitraum zwischen zwei Wellen vieler ankommender Flüge abzufertigen. Um genug Freiraum für Abflüge zu haben, ist die Koordination mit den Approach Positionen unumgämglich

You should assign top priority to inbound traffic not to outbound traffic to keep fluent traffic in rush-hour situations. In case of high traffic the use of slots and departure intervals are recommended. A slot is a period of time in which a pilot should be airborne. One slot is followed by another, continuously. Departure intervals are a certain period of time between two high traffic inbound waves. These departure intervals are used to get rid of outbound traffic. Coordination with approach positions to ensure more spacing between inbounds is necessary.

Phrasenzusätze in Situationen mit erhöhtem Verkehrsaufkommen

Um den Piloten eine Anweisung mit Nachdruck bekannt zu machen sollen folgende Phrasen angehängt werden. Dies ist vor allem bei der Runway Sseparation anzuwenden.

Austrian 125, are you ready for immediate departure?
Austrian 125, wind is xxx/xx runway 29 cleared for takeoff, expedite

Für Traffic im Anflug, eine Möglichkeit die Runway schneller frei zu bekommen:

Austrian 125, wind is xxx/xx runway 34 cleared to land, vacate runway as soon as practicable

Um VFR Traffic rasch aus dem Abflugsektor zu bekommen gibt es folgende Möglichkeit:

OE-ABC, wind xxx/xx, runway 29 cleared for takeoff, after departure right turn as soon as practicable

Study Guide: Radar


The responsibilities of a Radar Controller is to maintain the required seperation between aircrafts all the time by using different techniques of sequencing.

Airspace Structure

LOWW is located very close to the Austrian state boundaries with Hungary, Slovakia and the Czech Republik and space within the TMA (Terminal Maneuvering Area) is very limited.
Arrivals are being transferred to LOWW_APP by five independently working ACC sectors (LKAA/ACC Praha, LZBB/ACC Bratislava, LHCC/ACC Budapest, ACC Wien South, ACC Wien North). Therefore final decisions on the arrival sequence are normally made at a distance of approximately 40 NM from touchdown.

LOWW_APP itself operates up to four different sectors, depending on the amount of traffic. Two Upper Radar sectors specify the arrival sequence for the Lower Sectors. Upper Sectors are operated between FL240 and FL110.

The Lower Radar (FL100 and below) will then make final decisions on the arrival sequence by transferring arriving aircraft to the Director, who issues vectors onto the final approach track and sets up a safe flow of landing traffic. Unless otherwise instructed, initial contact on Director frequency (normally 119.800) shall be made by stating the callsign only in order to reduce frequency load.

When the appropriate spacing is assured until touchdown, Director will transfer the arriving aircraft to Tower.

Minimum Radar Separation

A Controller has to make sure that two Aircraft which are under his control never get closer than the minimum radar seperation. If two aircraft get closer than that, this incident is called a conflict.

  • The standard Minimum Vertical Seperation is 1000 ft up to FL290 and 2000 ft above that. However Austria is considered RVSM (Reduced Vertical Seperation Minima) airspace so the upper limit of the 1000 ft seperation minimum is raised to FL410. In real life this demands special equipment of the aircraft involved, however on VATSIM all aircraft are considered RVSM capable.
  • The Minimum Horizontal Seperation depends on the radar equipment involved. APP Sectors work with a minimum of 3 nm, CTR Sectors use 5 nm.

There are some cases where these minima may be under-run such as visual seperation or formation flights.


MRVA (Minimum Radar Vectoring Altitude): The MRVA is defined as the lowest available altitude above Mean Sea Level (MSL) in controlled airspace under consideration of the MSA (Minimum Safe/Sector Altitude) above ground and the airspace structure within a specified area.

MSA (Minimum Safe/Sector Altitude): Minimum Sector Altitude is the minimum altitude that may be used under emergency conditions which will provide a minimum clearance of 1000ft above obstacles and terrain contained within a sector of 25 NM radius centred on a radio navigational aid. MSA can be given as areas between radials from a VOR at the airport.

MOCA (Minimum Obstacle Clearance Altitude): This is the lowest altitude that an aircraft can fly in IMC (Instrument Meteorological Conditions) and still keep safe clearance from terrain and obstacles. MOCA is often lower then MEA (se below). It is only used in emergencies, especially to get below icing.

Structure of Flightplans and Routings


SID (Standard Instrument Departure): It is a pre-defined route which aircrafts have to fly to get to their initial airway to follow their desired routing to their destination.

e.g.: Flightplan from LOWW (Wien) to Salzburg (LOWS): SITNI L856 SBG DCT - SITNI is our first waypoint of our routing and let us say for instance that in Vienna Runway 29 is in use. We take a look at our charts and we see that we can plan for a socalled SITNI4C departure route.

SIDs are specified by the local Air Traffic Control. A SID can contain the following navigation aids: R-NAV Waypoints, VORs, NDBs, etc.


STARs (Standart Terminal Arrival Routes): STARs are pre-defined routes to get an aircraft to the airport.

A STAR falls into three parts namely navigational point, version number and runway (depending on the airport), e.g. GAMLI4W arrival. The point at which the STAR ends is called Initial Approach Fix (IAF). In some cases the STARs continue and end at the Final Approach Fix (FAF), and that means that you as controller don't need to vector the aircraft unless there is other traffic in the way. The only thing you have to do is to instruct the pilot how to descend the aircraft.

There are exceptions of course, where the STARs don't end at the final, but at a navigational point some distance away from the runway. You as a controller must give vectors the last part to the runway. If you for some reason don’t give vectors, the pilot must enter holding at the STAR's ending point (clearance limit).

Types of Instrument Approaches

An instrument approach or instrument approach procedure (IAP) is a type of air navigation that allows pilots to land an aircraft in reduced visibility (Instrument Meteorological Conditions [IMC]) or to reach visual conditions permitting a visual landing.

There are 2 types of approaches:

  • Precision Approaches
  • Non-Precision Approaches

1.) Precision Approaches

- ILS (Instrument Landing System)
- MLS (Microwave Landing System)
- PAR (Precision Approach Radar)
- GPS (Global Positioning System)
- LAAS (Ground Based Augmentation System [GBAS] for Global Satellite Navigation Systems [GNSS])
- JPALS (Joint Precision Approach and Landing System)
- GCA (Ground Controlled Approach)

2.) Non-Precision Approaches

- Localizer
- NDB (with ADF)
- Localizer Type Directional Aid (LDA)
- Simplified Directional Facility (SDF)
- GPS (Global Positioning System)
- Surveillance Radar Approach (SRA) [also known in some countries as ASR approach]
- Visual

Seperation and Sequencing Techniques


LOWW_APP is aiming at a maximum of 15 minutes flight extension for sequencing of arrivals to LOWW within the TMA (Terminal Maneuvering Area). Arriving aircraft will normally get radar vectors to one common downwind.


There are 2 types of vectoring:

  • Lateral Vectoring
  • Vertical Vectoring

1.) Lateral Vectoring

- ABC123, turn left heading 165°
- DEF243, turn right heading 300°

When issuing a heading to an aircraft, make sure that you are using a direction ending on 0 (zero) or on 5 (five).

If you provide Radar Vectors to an aircraft then always tell the pilot the reason why you are doing this:

- "ABC123 turn right heading 080°, radar vectors for ILS approach RWY 11"

2.) Vertical Vectoring

- ABC123, climb FL240"
- DEF243, descent Altitude 3000 feet, QNH 1016"

As you can see there are 2 types of heights namely Altitude and Flightlevel (FL).

Flightlevel is used for aircraft flying above the Transition Altitude, Transition Level or climbing through and above the Transition Layer (Altimeter in the aircraft is set to Standart Pressure [1013 QNE]).

Altitude is used for aircraft flying below the Transition Altitude or for Aircraft descending through and below the Transition Layer (Altimeter in the aircraft is set to local QNH).

Speed Control

For efficient sequencing and spacing of arriving aircraft LOWW_APP (Wien Radar) will instruct specific indicated airspeeds to be maintained (speed control). Aircrews are expected to maintain instructed speeds as accurately as possible (+ / - 10knts). In case of unability to maintain instructed speed (weather reasons, operating limitations etc.) ATC has to be informed immediately.


  • Useage
    • The primary use of a holding is delaying aircraft that have arrived over their destination but cannot land yet because of traffic congestion, poor weather, or unavailability of the runway. Several aircraft may fly the same holding pattern at the same time, separated vertically by 1,000 feet or more.
  • Flying a Hold
    • Most aircraft have a specific holding speed published by the manufacturer.Maximum holding speeds are established in order to keep aircraft within the protected holding area during their one-minute inbound and outbound legs.

As a rule of thumb the Speed to be flown depends on the altitude or flight level the aircraft is at within the hold as follows:

   * At 6,000' MSL and below: 200 knots
   * From 6,001' to FL 140: 230 knots
   * At and above FL140: 265 knots
  • Duration

A Complete hold should take:

   * FL140 and below 4 minutes
   * FL140 and above 5 minutes
  • Holding Clearance
    • A holding clearance issued by ATC includes at least:
- A clearance to the holding fix.
- The direction to hold from the holding fix.
- A specified radial, course, or inbound track.
- If DME is used, the DME distances at which the fix end and outbound end turns are to be commenced.
- The altitude or FL to be maintained. 
- The time to expect further clearance or an approach clearance.
- The time to leave the fix in the event of a communications failure.
  • Standart Holding Pattern
   * Standard Hold: A hold where all turns are made to the right
   * Non Standard Hold: A hold where all turns are made to the left
   * Holding Course: The course flown on the inbound leg to the holding fix.
   * Inbound Leg: The standard 1 or 1.5 minute leg to the holding fix as Published
   * Holding Fix: This can be a VOR, a VORDME, an Intersection or an NDB
   * Outbound Turn: A standard rate, 180 degrees turn which is begun at the holding Fix.
   * Abeam: The position opposite the holding fix, where the outbound begins.
   * Outbound Leg: This leg is defined by the inbound leg, pilots should adjust the outbound leg so that the inbound turn, the other standard 180° turn is completed just as the holding course is intercepted.
   * Holding Side: The side of the course where the hold is accomplished.
   * Non Holding Side: The side of the course where you do not want the pilot to be holding
  • Non Standart Holding Pattern

A non-standard holding pattern is one in which

- The fix end and outbound end turns are to the left; and/or
- The planned time along the inbound track is other than the standard one-minute or one-and-a-half minute leg appropriate for the altitude flown.
  • Entry Holding Procedure
    • Direct Entry (aircraft flies directly to the holding fix, and immediately begins the first turn outbound)
    • Parallel Entry (aircraft flies to the holding fix, parallels the inbound course for one minute outbound, and then turns back, flies directly to the fix, and proceeds in the hold from there
    • Teardrop Entry or Offset Entry (aircraft flies to the holding fix, turns into the protected area, flies for one minute, and then turns back inbound, proceeds to the fix and continues from there).

Coordination with adjacent Sectors

The coordination respectively the communication between controllers (and of course pilots) is on of the most important things in aviation.

A clear instruction to the person I want to speak to falls into 4 parts:

- Who am I calling
- What do I want
- How are we going to archieve this (short and clear instructions!) 
- Did the person I called unterstand my instruction properly

VFR Traffic

Flight Information Positions

Flight Information Service (FIS) is an air traffic facility that provides a myriad of services to the pilot, such as pilot briefings, relaying of clearances and broadcasting of weather information. At selected locations, FIS also provides en-route Flight Advisory Services.

Abnormal Situations - Emergencies, Radio Failures


Emergencies are very uncomfortable situations for every controller. Emergencies shall be handeled expeditiously to get them safe down to the ground.

Note: The pilot tells the ATC what his intentions are and what he will do next and not the other way round. ATC keeps all the traffic in the vicinity of the emergency aircraft away to assure that no other aircraft gets injured.

All Weather Operations (AWO)
With Low Visibility Procedures in operation, standard approach runway will be runway 16.
Arrivals will be vectored out of the holdings into the left hand circuit for runway 16. Approximate track distance from the holdings to touchdown shall be calculated with 40 to 70 nautical miles.

Controlling CTR Positions

Area Control Center (ACC) provides ATC to aircraft on the en-route phase of flight. This includes giving information that the pilot needs such as weather and traffic information. The ACC controller has to assure that the seperation is always appropriate regarding to the traffic in the vicinity ( 5 nautical miles lateral, 1000 feet vertical at least ).

ACC is also responsible for all airports where Tower and Approach are not manned. If you are working on the ACC position always remember that this position is a demanding position and requires great knowledge and experience.

Study Guide: Airport Details

LOWW (Wien Schwechat)


  • 11/29: Beton, 3500x45 Meter, ILS
  • 16/34: Beton, 3600x45 Meter, ILS

Visual Approches

Approaches using "Own Separation". Visual Approaches will be issued whenever the traffic situation permits. Due to several noise sensitive areas in the vicinity of Vienna Airport, LOWW_APP has to impose certain restrictions on visual approaches:

  • NO visual or short approaches will be issued in the right-hand circuit for runway 16 and in the left-hand circuit for runway 11 (City of Vienna).
  • Aircraft instructed to "maintain own separation" during final approach are expected to maintain a safe and efficient separation (normally less than 2,5 NM) to the preceding landing aircraft.

Possible Runway Configurations

The runway utilization concept for LOWW is based on the fact that the airport layout with it's crossing runways normally does not allow simultaneous approaches to both runways. So, whenever possible, runways 11/29 and 16/34 will be used independently to allow departures on one runway (normally 16 or 29) while using the other runway for landing aircraft.

Possible runway configurations are:

  • ARR RWY 11 / DEP RWY 16 >>> SE winds, if no simultaneous approach possible
  • ARR RWY 34 / DEP RWY 29 >>> calm/NW winds
  • ARR RWY 16 / DEP RWY 29 >>> calm/SW winds
  • ARR RWY 11/16sim. / DEP RWY 16 >>> calm/SE winds, simultaneous approach possible

Simultaneous approaches to runways 11 and 16 are conducted only at tower's discretion during certain weather conditions (visual reduction of separation). Aircrews are advised to show landing lights as soon as possible.
In case of technical uncertainties during final approach - that might be possible lead to a missed approach - aircrews are asked to inform ATC immediately.

LOWL (Blue Danube Airport)


  • 09/27: Beton mit 3 Kilometer Länge und 60 Meter Breite
  • 09/27 (Gras): Graspiste mit 660 Meter Länge und 45 Meter Breite.


Folgende Anflugverfahren beziehen sich nur auf die Piste 09/27. Die parallele Graspiste ist nur per Sicht anzufliegen.

  • ILS:
    • Richtung 27 bis CAT IIIb (109.30, Finalapproachtrack: 266°)
    • Richtung 09 nur CAT I (110.55, Finalapproachtrack: 086°)
  • VOR (LNZ, 116.600):
    • Primär Richtung 09 (Radial 086)
    • Mit Platzrundenanflug Richtung 27 (Radial 086, Wegbrechen nach Süden)
  • NDB (LNZ 327):
    • Primär Richtung 27 (Radial 266)
    • Mit Platzrundenanflug Richtung 09 (Radial 266, Wegbrechen nach Süden)

ATC-Stationen in Linz

In Linz gibt es folgende zwei Stationen:

  • LOWL_TWR (Linz Turm) auf 118.800
  • LOWL_APP (Linz Radar) auf 129.620

Besonderheiten in Linz

  • In Linz dürfen Platzrundenanflüge (Visualcirclings) nur in südliche Richtung gemacht werden!
  • Der Bereich südlich der Piste 27-09 ist militärisches Gelände!
  • Für größere Flugzeugtypen stehen in Linz folgende Parkpositionen zur Verfügung:
    • Position 13 bis zur Boeing 747-400
    • Position 11 auch bis Boeing 747-400 (Wenn auf 11 und 13 B744 sind, kein Platz auf 12)

LOWS (Salzburg Maxglan)


  • 16/34: Beton mit 2.75 Kilometer Länge und 45 Meter Breite


  • ILS: Richtung 16 bis Special CATIII (109.90 OES, Finalapproachtrack: 156°)
  • NDB: (SBG 382.0), primär Richtung 16 (Radial 156)
  • Visual Circling:, Richtung 16 bis SI 410.0 (Radial 336, wegbrechen nach links)

ATC Stationen in Salzburg

In Salzburg gibt es folgende Stationen:

  • LOWS_DEL (Salzburg Delivery) auf 121.750
  • LOWS_TWR (Salzburg Tower) auf 118.100
  • LOWS_APP (Salzburg Radar) auf 123.720




  • 08/26: Betonpiste mit 2000 (6562´) Meter Länge und 45 Meter (148´) Breite


  • LOC/DME EAST (111.10 OEV)
  • LOC/DME WEST (109.70 OEJ)

ATC Stationen in Innsbruck

  • LOWI TWR (Innsbruck Tower) 120.100
  • LOWI_APP (Innsbruck Radar) auf 119.275




  • 10/28: Beton mit 2720 Meter (8294') Länge und 45 Meter Breite
  • 10R/28L Graspiste mit 710 Meter (2329') Länge

Folgende Anflugverfahren stehen für Klsgenfurt zur Verfügung für die Piste 10/28:

  • ILS
    • 28: 110.10 (OEK) 285°
  • NDB
    • 10: 405 (KW) 105°

ATC-Stationen in Klagenfurt

  • LOWK_TWR (Klagenfurt Tower) auf 118.100
  • LOWK_APP (Klagenfurt Radar) auf 126.820


Graz Thalerhof


  • 17L/35L: Grasspiste mit 760 (2493´) Meter Länge und 30 Meter (98´) Breite
  • 17C/35C: Betonpiste mit 3000 (9843´) Meter Länge und 45 Meter (148´) Breite
  • 17R/35R: Grasspiste mit 640 (2100´) Meter Länge und 25 Meter (82´) Breite


Folgende Anflugverfahren stehen für Graz zur Verfügung für die Piste 17C/35C:

  • ILS
    • 35C: 110.90 / 348°
    • CAT II / III: 110.90 / 348°
    • 17C: 116.20 (GRZ VOR) / 168°
    • 35C: 116.20 (GRZ VOR) / 348°
  • NDB
    • 35C: 290 (GRZ NDB) / 348°
  • GPS
    • 35C: OWG01 / 348°

ATC-Stationen in Graz

  • LOWG_TWR: 118.200
  • LOWG_APP: 119.300
  • LOWG_ATIS: 126.120