Figure 6.1 Proposed Three-Runway Alignment and Operating Mode Copyright©CNES 2011, distributed by Spot Image 6 PRACTICAL MAXIMUM RUNWAY CAPACITY Further to the practical maximum runway capacity assessed for the two-runway system as explained in Chapter 4, National Air Traffic Services (NATS) has also evaluated the practical maximum capacity increase that could be achieved with a third runway. NATS concluded that the three-runway system could support a practical maximum runway capacity of 102 ATMs per hour with the following arrangements – (a) The Third (new) runway dedicated for “arrivals” only; (b) The Second (existing North) runway dedicated for “departures” only; and (c) The First (existing South) runway for both “arrivals” and “departures”. Following the same considerations as explained in Chapter 4, the practical maximum runway capacity of 102 ATMs per hour could be translated into practical maximum daily movements of about 1,800 ATMs per day and practical maximum annual capacity of about 620,000 ATMs per year. There could be potential to further increase the runway capacity in future with enhancements in aircraft and air traffic control technology and management of the Pearl River Delta (PRD) airspace. AIRPORT DEVELOPMENT LAYOUT CONFIGURATION In terms of the alignment of the third runway, NATS has investigated a total of 15 alignment options with regard to operational safety, obstacle clearances, environmental issues, PRD airspace issues, air traffic control procedures, runway usability and capacity. NATS concluded that the best alignment for a third runway would be parallel to and north of the existing two runways. Based on the recommended parallel alignment of a third runway, 18 different airport layout options OPTION 2: THREERUNWAY SYSTEM HKIA MASTER PLAN 2030 33