Tower

Tower


Clearance		Ground		Tower		Approach Radar		Area Control		FIS

Description

Tower controllers are responsible for issuing information and instructions to aircraft under their control to achieve a safe, orderly and expeditious flow of air traffic and to assist pilots in preventing collisions between aircraft flying in, and in the vicinity of the aerodrome traffic zone and aircraft taking off and landing.

In the absence of Ground and Clearance Delivery controllers, Tower controllers will take over the tasks assigned to Ground and Clearance Delivery.

It's the Tower controller that defines the active runways for a given airport, and ultimately decides who lands on which runway. The Tower controls the upflow of traffic into controlled airspace, and is an essential link in the chain of Air Traffic services. It is essential for Tower Controllers to maintain constant contact with the Approach Radar/Area controller, as well as Ground and Delivery.

Area of responsibility

The tower is responsible for all active runways, and for VFR traffic operating within the Control Zone (usually a radius of 15nm, up to 2500ft AGL).

IFR departures from Dublin airport should be told to contact the next controller right after airborne. The departure frequency will be given to the flight crew during the clearance.

What you need to know

In addition to the general guidelines a Tower Controller must:

be familiar with the Clearance Delivery procedures,
be familiar with the Ground Movement procedures,
read chapter 9, 10 and 11 of ICAO doc 9432 - Manual of Radiotelephony,
understand the different airspace divisions around the airport,
understand any preferential runway assignments,
understand noise abatement procedures when applicable,
know all separation minima for arriving/departing traffic.

Procedures

Firstly you'll need the following information:

The sector file for the given airport,
The complete collection of charts for the selected airport.

The term "runway-in-use" is used to indicate the particular runway or landing direction selected as the most suitable. Normally, it should be the runway most closely aligned to the surface wind direction.

When selecting the runway-in-use, other factors such as traffic pattern, noise abatement procedures, the length of runways, or landing runs and the approach aids available should be taken into account. At certain aerodromes more than one runway may be in use at any one time.

Should a change of runway be necessary, Tower must inform approach control, area control, and aircraft under their control.

When line-up will take place at a position other than for a full-length runway departure the intermediate "holding point" designator shall be included in the line-up instruction.

ATC: "REA82F, via E6, line up runway 10"

The Tower controller is responsible for issuing take-off clearance and advising pilots of any variations to the surface wind or other significant changes to meteorological conditions.

When multiple runways are in use, the take-off clearance shall include the designator of the departure runway.

One runway in use:

ATC: "REA82F, cleared for take off"

Pilot: "Cleared for take off, REA82F"

Multiple runways in use:

ATC: "REA82F, runway 10, cleared for take off"

Pilot: "Cleared for take off runway 10, REA82F"

The controller may request the pilot to report when airborne. Normaly this is done when the Tower doesn't have the aircraft visual, at night or during bad weather.

ATC: "REA82F, [runway 10] cleared for take off, report airborne"

Pilot: "Cleared for take off [runway 10], wilco, REA82F"

If the wind is significantly different from the ATIS, you should also add the wind in a take off clearance.

ATC: "REA82F, [runway 10], cleared for take off, [surface] wind 120 degrees at 13 knots"

Take-off clearance may be issued when aircraft is at or approaching the holding point for a runway.

If the take-off clearance has to be cancelled before the take-off run has commenced, the pilot shall be instructed to hold position.

ATC: "REA82F, hold position, cancel take-off, I say again, REA82F cancel takeoff"

Pilot: "Holding, REA82F"

When an aircraft has commenced the take-off roll, and it is necessary for the aircraft to abandon take-off in order to avert a dangerous traffic situation, the aircraft should be instructed to stop immediately and the instruction and call sign repeated.

ATC: "REA82F, stop immediately, REA82F, stop immediately"

Pilot: "Stopping, REA82F"

If for any reason, you need an aircraft to take off immediately. It is expected that the pilot will act as follows:

At the holding point, taxi immediately onto the runway and commence take-off without stopping the aircraft (Not to be used with heavy aircraft).
If already lined up on the runway, take-off without delay.

You should always ask the pilot before giving the clearance if he is able to accept an immediate take-off.

The phrase "cleared for immediate take off" is not used in Ireland.

ATC: "REA82F, are you ready for immediate departure"

Pilot: "Affirm, REA82F"

ATC: "REA82F, Line up runway 10, be ready for immediate departure"

Pilot: "Lining up runway 10, REA82F"

ATC: "REA82F, runway 10, cleared for take off"

Pilot: "Cleared for take off runway 10, REA82F"

During a flight a pilot may change from IFR to VFR. This can only be done when VMC are met.

Pilot: "Shannon Control, REA82F, canceling IFR flight, proceeding VFR, estimating Sligo at 1806"

ATC: "REA82F, IFR flight cancelled at 34, contact Shannon Information at 127.5"

Pilot: "127.5, REA82F"

Except in cases of emergency, controllers should not transmit to an aircraft in the process of taking off or during the early stage of climb.

Normaly aircraft should be handed off to the next controller once airborne, preferably before 2000ft.

VFR Procedures

VFR flights are flights flown within Visual Meteorological Conditions (VMC). In Irish airspace VMC conditions are met according to the table below.

Airspace	Class C	Class G	Class G
Altitude	Class C	Above 900 metres (3000ft) AMSL or above 300 metres (1000ft) above terrain whichever is higher	At and below 900 metres (3000ft) AMSL or 300 metres (1000ft) above terrain whichever is higher
Distance from cloud	1500 metres (5000ft) horizontally 300 metres (1000ft) vertically		Clear of cloud and in sight of the surface
Flight Visibility	8 Kilometres at or above FL100 AMSL 5 Kilometres below FL100 AMSL		* 5 Kilometres: speed > 140 3 Kilometres: speed < 140 1500 Metres: speed < 100 < 1500 Metres for helicopters

*
Adjusted for IVAO needs.

Traffic Circuit

An aircraft will normaly contact you before entering the Control Zone (CTR), the Tower Controllers gives clearance to enter a Control Zone.

When the traffic circuit is in a right-hand pattern this should be specified. A left-hand pattern need not be specified although it may be advisable to do so.

Example of a right hand pattern

Pilot: "Dublin Tower, EICCN, Cessna 172, 10nm north of control zone, 1500ft, information Mike, for landing"

ATC: "EICCN, squawk 0061"

Pilot: "Squawk 0061, EICCN"

ATC: "EICCN, join right hand downwind runway 29, wind 290 at 12 knots, QNH 1019"

Example of a left hand pattern

Pilot: "Dublin Tower, EICCN Cessna 172, 10nm north of control zone, 1500ft, information Mike, for landing"

ATC: "EICCN, squawk 0061"

Pilot: "Squawk 0061, EICCN"

ATC: "ECN, join downwind runway 11, wind 120 at 11 knots, QNH 1011"

Pilot: "Join downwind runway 11, QNH 1011, ECN"

ATC: "ECN, traffic, Beech 58, taking off runway 11 and a Cherokee on downwind"

Pilot: "Traffic in sight, ECN"

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Pilot: "Downwind, ECN"

ATC: "ECN, number two, follow Cherokee on base"

Pilot: "Number two, traffic in sight, ECN"

---

Pilot: "ECN, base"

ATC: "ECN, report final"

Pilot: "ECN"

---

Pilot: "ECN, final"

ATC: "ECN, continue approach, wind 120 degrees, 11 knots"

Pilot: "Continue, ECN"

ATC: "ECN, number one, runway 11, cleared to land, wind check, 130 degrees 8 knots"

Pilot: "Cleared to land runway 11, ECN"

Depending on prevailing traffic conditions and the direction from which an aircraft is arriving, it may be possible to give a straight-in approach.

Pilot: "Dublin Tower, EICCN Cessna 172, 10nm east of control zone, 1500ft, information Mike, for landing"

ATC: "ECN, make straight-in approach runway 29, wind 260 degrees 5 knots, QNH 1009"

Pilot: "Straight-in runway 29, QNH 1009, ECN"

In order to coordinate traffic in the circuit, it may be necessary to issue delaying or expediting instructions.

Some examples:

ATC: "ECN, extend downwind, number 2, follow cherokee on 4 miles final"

Pilot: "Extending downwind, number 2, cherokee in sight, ECN"

---

ATC: "ECN, orbit right due traffic on the runway. Report again on final."

Pilot: "Orbiting right, wilco, ECN"

Aircraft reports on "downwind" leg when abeam upwind end of the runway.

Aircraft reports "late downwind" if it is on the downwind leg, has been unable to report "downwind" and has passed the downwind end of the runway.

Visual Control

IVAO has released a program called IvAi, which enables you to see all traffic in flight simulator when controlling. This way you can have a better view on what is happening on the airport.

IvAc settings

We recommend you switch Ground detail, VORs, NDBs and Runway centrelines on.

Set your altitude filter to the top of your area of responsibility + 1500ft (for example: SFC - 2500ft, you would set the filter to SFC - 4000ft), and use a range of 25nm.