PRACTICAL MAXIMUM CAPACITY OF HKIA’S TWO-RUNWAY SYSTEM According to the 1992 published New Airport Master Plan (NAMP), Hong Kong International Airport (HKIA) was designed to handle an ultimate capacity of 87 million passengers, 8.9 million tonnes of cargo and 376,000 air traffic movements (ATMs, also known as flight movements) per annum in 2040. However, the latest base-case traffic demand forecast from International Air Transport Association (IATA) Consulting by 2030 is 97 million passengers, 8.9 million tonnes of cargo and 602,000 ATMs per year. The main reason for the discrepancy between the 1992 NAMP and the IATA Consulting estimates for annual ATMs is that many of the working assumptions adopted back in early 1990s were based on the operating environment of Kai Tak Airport which at that time was highly constrained and fully stretched – (a) The 1992 NAMP assumed the forecast flights at HKIA would comprise a very high percentage of wide-bodied aircraft (84%), resulting in a high average passenger load forecast of over 300 people per aircraft. When Kai Tak exhausted its runway capacity, it was natural that airlines maximised the value of each slot by deploying the biggest aircraft possible. The opening of HKIA with two runways has provided more runway capacity for airlines to increase frequency, serve new secondary destinations (especially on the Mainland) and deploy narrow-bodied aircraft (less than 200 seats) on routes that have yet to mature. The average passenger load per aircraft as a result decreased from around 200 at airport opening in 1998 to about 190 since 2000. For the same passenger throughput of 87 million passengers, IATA Consulting forecasts that it would entail 437,000 ATMs, instead of 278,000 ATMs that were originally estimated in the NAMP. (b) The 1992 NAMP also assumed extensive use of wide-bodied freighters (for example, B747F of 100 tonnes) and lower than actual cargo tonnage carried by freighter at 45% of the total cargo throughput. As it turns out, the extraordinary growth of the cargo market in the last decade (supported by the Government’s progressive liberalisation policies on air services) and the rapid 22