As already been established by SC4 there are many of areas of concern within aerodrome control regarding surface movement. This paper attempts to provide some legal guidelines to assist the aerodrome controller, especially when operating in conditions of restricted or poor visibility.

The aim of an ATC service, imprinted on the mind of every controller and enshrined in the foundation of air traffic control is to ensure a safe, orderly and expeditions flow of traffic. Separation between aircraft/vehicles on the manoeuvring area is based on visual observation principles but in recent years this concept is slowly being eroded and the control tower often does not afford the controller with the required vision of such operational areas.

At all airports direct visual observation from the control tower is an essential factor that governs the ability of aerodrome controllers to undertake their responsibilities in the monitoring and control of aircraft and vehicles on the manoeuvring area. It must therefore be stated that aerodrome controllers cannot be held liable for incidents that occur out of sight of the tower. The use of CCTV whilst helpful in some circumstances, should only be considered an aid, and must not take the place of direct visual observation.

Apron areas are usually particularly congested and often poorly sited with respect to direct vision from the tower, it cannot therefore be expected that controllers will be responsible for the safe movement of aircraft in these areas. It is preferable that an apron management service is established, and it’s responsibilities clearly defined. In poor weather it is essential that safety is maintained, and although the aircraft’s commander is ultimately responsible for the safety of the aircraft by keeping a good look-out, low visibility limits the effectiveness of this.

As far as the aerodrome controller is concerned aircraft position needs to be accurately determined in order that safe clearances can be issued. Equipment that enables this to occur must be provided, and should be considered mandatory where movements are approved to Category 2 and 3 minima. Unless this essential equipment is provided, the liability of controllers operating in poor visibility must be strictly limited.

In order to complete his task effectively and safely the aerodrome controller must be able to visually observe the whole of the area under his control. The use of CCTV is at best only a supplement to direct observation and should not be used as an alternative. Because the aerodrome controller issues clearances based on what he sees, he should not be held liable for incidents that occur out of sight of the tower.

In conditions of poor visibility the aerodrome controller must be provided with a surface movement radar system which provides adequate information to allow safe and efficient instructions to be issued to aircraft on the ground. This should be a mandatory requirement where Category 2 and 3 operations are approved.

Because of the congested nature and siting problems associated with many apron areas, it cannot be expected that aerodrome controllers will be responsible for the safe movement of aircraft in these areas. In these circumstances an apron management service with clearly defined areas of responsibility should be established.

The responsibilities of apron management service, where provided, must be clearly defined, aerodrome controllers cannot be held liable for incidents that occur under the jurisdiction of such a service.

The following policy should be inserted on IFATCA manual page 4413 paragraphs 1.2.7 – 1.2.8:

An aerodrome controller cannot be held liable for any accident or incident that might occur on that portion of the aerodrome under his control, unless direct visual observation of the area concerned is practicable or a surface movement surveillance system is in use.

Where an apron management service is established, aerodrome controllers cannot be held liable for accidents or incidents that occur whilst aircraft are under the jurisdiction of such a service.

IFATCA Working Paper C.129/96.