This Regulation lays down common airspace usage requirements and operating procedures for airborne collision avoidance to be fulfilled by:

1. (a)

   operators of aircraft referred to under Article 4(1)(b) and (c) of Regulation (EC) No 216/2008 undertaking flights into, within or out of the F4United Kingdom; and

2. (b)

   operators of aircraft referred to under Article 4(1)(d) of Regulation (EC) No 216/2008 undertaking flights within the airspace F5of the United Kingdom.

For the purposes of this Regulation the following definitions shall apply:

1. (1)

   ‘airborne collision avoidance system (ACAS)’ means an aircraft system based on secondary surveillance radar (SSR) transponder signals which operates independently of ground-based equipment to provide advice to the pilot on potential conflicting aircraft that are equipped with SSR transponders;

2. (2)

   ‘airborne collision avoidance system II (ACAS II)’ means an airborne collision avoidance system which provides vertical resolution advisories in addition to traffic advisories;

3. (3)

   ‘resolution advisory (RA) indication’ means an indication given to the flight crew recommending a manoeuvre intended to provide separation from all threats or a manoeuvre restriction intended to maintain existing separation;

4. (4)

   ‘traffic advisory (TA) indication’ means an indication given to the flight crew that the proximity of another aircraft is a potential threat.