Control of Aircraft

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figure stated. This is the range at which the radar service will be automatically terminated. RTR

stands for Radar Termination Range. Typically RTR2 is used indicating that the radar service will

be terminated at 2 NM from the threshold of the landing runway. During the procedure, the

pilot is passed magnetic headings to fly and corrections (left or right) to the extended centre

line of the landing runway. If the RTR is 2, distance information is passed (with advisory height

information) every 1 NM. If RTR1 is applicable, range and height information is passed every

0.5 NM. As for PAR, the radar controller will be responsible for obtaining a landing clearance

from the aerodrome controller and passing it to the pilot. The approach plate for the SRA

approach to Gatwick is shown in Figure 17.5.

Aerodrome Control

17.18 Introduction. The responsibility for avoiding collisions involving aircraft, obstacles,

vehicles and personnel on or in the air in the vicinity of an aerodrome rests with the aerodrome

controller. At a ‘controlled aerodrome’ (see definition) the aerodrome controller usually

operates from the visual control room (VCR) situated at the top of the control tower. The VCR

normally allows the aerodrome controller to see all parts of the aerodrome but may also have

electronic aids to assist the controller when visibility is poor or at night. The primary duty of

the aerodrome controller is to control access to the runway in use. The nature of the service

offered is procedural, with the pilot telling the aerodrome controller where the aircraft is and

the controller basing any instructions or clearances on that information. For departing aircraft

the aerodrome controller will give a take-off clearance which will be de-facto permission to

enter and take off from the runway. Once airborne the pilot will report ‘airborne’ at which

time another aircraft can be cleared to use the runway.

17.19 Use of the Runway. The aerodrome controller will normally decide which runway will

be used for take-off and landing operations. The ‘runway-in-use’ will determine the direction

for instrument approaches and the direction for the visual circuit. Normally, the wind direction

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will be the deciding factor; however, in calm or light wind conditions, another direction may be

preferable for ATC, airspace restriction or noise abatement requirements. At London Heathrow,

Aircraft

a departing aircraft will be expected to accept a 5 kt tail wind and use the noise preferential

runways. It is a generally accepted practice that only one aircraft is permitted on the runway

of

at any time.

Control

17.20 Departing Aircraft. Aircraft waiting for take-off will be held at a runway holding point

on the taxiway at a safe distance from the centre line of the runway. It is normal procedure for

aircraft to be given a ‘take-off immediate’ clearance. This requires the pilot to taxi the aircraft

on to the runway and without stopping, line the aircraft on the centre line and then apply the

necessary power to commence the take-off run. A succeeding aircraft may be permitted to

enter the runway (given the instruction ‘line up and wait’) as soon as the preceding aircraft has

commenced the take-off run. A succeeding aircraft will not be given clearance to take off until

the preceding aircraft has either crossed the upwind threshold, or has commenced a turn away

from the runway direction.

17.21 Arriving Aircraft. When established on final approach, an arriving aircraft will be given

clearance to land if the runway is available. For an arriving instrument approach, the clearance

to land will normally be given at about 4 NM from the threshold and certainly no later than 2

NM from the threshold. If the pilot of an arriving instrument approach has not been given a

landing clearance, the missed approach procedure is to be flown commencing at 2 NM. Once

the landing run is complete and the pilot has turned the aircraft onto the taxiway, he/she is

required to make a report to the aerodrome controller to confirm that the aircraft has ‘vacated

the runway’. This is to be made when all of the aircraft has passed the appropriate holding

point.

aircraft.

17.23 “Land After” Clearance. Under certain conditions, a pilot may be given a provisional

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clearance to “land after the preceding aircraft”. This will be done to increase the utilization

ofControl

of the runway at peak times so that aircraft may arrive at 1 minute intervals. In this case, the

the time he/she lands and that there is sufficient separation between the aircraft throughout

pilot of the second aircraft will decide if the preceding aircraft will be clear of the runway at

Aircraft

the manoeuvre. Throughout the landing, the pilot of the following aircraft must be able to

see the previous aircraft and is responsible for maintaining separation. In this case, the pilot

of the following aircraft will apply the appropriate visual separation which may be less than

the procedural separation. The provision of ‘fast turn off lanes’ or ‘rapid exit taxiways’ on

aerodromes enhances this option. The necessary conditions are:

• Only permitted during daylight;

•

•

• The pilot and operator of the aircraft concerned must be aware that the runway occupancy

•

• Direction of take-off and turn after take-off,

•

• Level to maintain before continuing climb to assigned cruising level,

• Time, point and/or rate at which level change shall be made,

• Any other necessary manoeuvre consistent with the safe operation of the aircraft.

17.29 Take-off direction. Departing aircraft may be expedited by suggesting a take-off

direction which is not into the wind. It is the responsibility of the pilot-in-command of an aircraft

to decide between making such a take-off, and waiting for normal take-off in a preferred

direction.

17.30 Delays. In order to avoid excessive holding at the destination, aircraft may be held

at the departure aerodrome prior to take-off. ATC is required to advise operators (or their

nominated representative) of substantial delays and in any case where the delay is expected to

exceed 30 minutes.

17.31 Information for Departing Aircraft. The following information is to be passed to

departing aircraft by the approach controller:

•

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of Control

•

Aircraft

•

• Speed control. The method of maintaining separation during sequenced instrument

approaches using radar is by asking the aircraft concerned to fly at specified a speed. It

is usual for an aircraft to start an instrument approach (from the IAF) at 210 kt (IAS). For

example a clearance might be: “Speedbird 289 leave Ockham heading 290 speed 210 kt”.

This is a speed that most commercial operations aircraft can achieve without having to

use drag or lift enhancing devices. If necessary, the speed of a subsequent aircraft will

be reduced to maintain the necessary time/distance interval between the aircraft. Speed

adjustments will be made in intervals of no more than 20 kt and required speeds will always

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be in multiples of 10 e.g. “Speedbird 289 maintain 180 kt”. During the latter stages of an

Aircraftof

approach, the pilot will need to reduce the speed to Vat so no further speed control will be

applied after the aircraft has passed 4 NM from touchdown.

Control

•

ATC unit) that he or she is not familiar with an instrument approach procedure, the initial

Unfamiliar procedures. If a pilot-in-command reports (or if it is clearly apparent to the

approach level, the point (in minutes from the appropriate reporting point) at which

procedure turn will be started, the level at which the procedure turn shall be carried out

and the final approach track shall be specified, except that only the last-mentioned need

be specified if the aircraft is to be cleared for a straight-in approach. The missed approach

procedure shall be specified when deemed necessary.

•

Visual reference to terrain. If visual reference to terrain is established before completion

of the approach procedure, the entire procedure must nevertheless be executed unless the

aircraft requests and is cleared for a visual approach.

•

• During final approach. The following information shall be transmitted without delay:

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• The sudden occurrence of hazards (for example: unauthorized traffic on the runway);

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•

of

Aircraft